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Dr. Eric Lander
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Meet the Decoders
Dr. Eric Lander
Krulwich: Let me see, let me just start with the gene
itself. First of all, we're all familiar with this thing.
This shape is very familiar.
Lander: Double helix, yes.
Krulwich: Double helix. First of all, this is my
version of a DNA molecule, but I'm just curious how small is
it in real life? Like the distance--is this by the way, what
it looks like?
Lander: Well, give or take, a cartoon version. Yes.
That's right.
Krulwich: This is made of what, these sort of
walls?
Lander: This chain here that runs along the outside
is made of sugar molecules and negatively charged phosphate
molecules. Then it goes:
sugar/phosphate/sugar/phosphate/sugar/phosphate, running all
along here, boring and utterly repetitive.
Krulwich: So if you lick it, it would be a little bit
sweet this part?
Lander: Well, no. It wouldn't because they're all a
patch. You see, it only tastes sweet if it comes off and
activates your taste receptors. So these long chains are not
very good.
Krulwich: Okay.
Lander: I mean wood is also made out of these sugars
and things, and it doesn't taste very sweet, because it's
all sown up.
Krulwich: Okay.
Lander: But if you broke it all up, there is a little
sugar in there.
Krulwich: The main thing about this is the ladder,
the steps of this ladder.
Lander: So the news is along these steps, right? The
outside is the same all along; the inside sticking out of
these sugars comes one of four different things, one of four
bases that we call A, T, C, or G. They correspond to
different funny molecular shapes with little rings and
things.
Krulwich: And when you say A, T, C -- I'm just going
to set this thing up here.
Lander: Okay. So let's say that this red guy here is
an A and that's a T.
Krulwich: Why do you call them A and T?
Lander: Oh, it's adenine and thymine.
Krulwich: So those are their initials?
Lander: But it's a fast-moving field. You can't say
adenine all the time and thymine and cytosine all the time
and guanine all the time, so you say, A, T, C, and G.
Krulwich: So there are in almost every cell in your
body, if you look deep enough, you will find this chain
here?
Lander: Oh, yes. Stuck to the nucleus of your cell
there is I guess 23 pairs of these chains called
chromosomes.
Krulwich: Right.
Lander: Each chromosome is a very long chain of about
anywhere 100 million rungs of the ladder.
Krulwich: In every cell?
Lander: Every cell.
Krulwich: Over and over. How many of these steps do
we have in a typical cell in me?
Lander: Well, you've got six billion, of which three
billion came from your mom and three came from your dad.
Those two copies are pretty similar, so every cell has a
genome of three billion, and it actually has about--it has
two copies of it; one from mom and one from dad.
Krulwich: Let's just think for a moment. Let's just
look at the whole landscape. The human being has 3.1 billion
of these letters, not all of them are genes, in fact only 1
percent of them are genes. So, where are they? Is there any
pattern?
Lander: The genome is very lumpy.
Krulwich: Very?
Lander: Very lumpy, very uneven. You might think, if
we have 30,000 genes, they're kind of distributed uniformly
across the chromosomes. Not so. They're distributed like
people are distributed in America: they're all bunched up in
some places, and then you have vast plains that don't have a
lot of people in them. It's like that with the genes. There
are really gene dense regions, that might have 15 times the
density of genes, sort of New York City over here. And there
are other regions that might go for two million letters and
there's not a gene to be found in there.
Krulwich: So there's this whole conversation going on
that we didn't know about, like, ten years ago.
Lander: The genome is, it's a fossil record; the
genome is a landscape; the genome is a whole geography of
distributions. The thing about the human genome that most
surprised me was how many amazing stories there were in it.
That you might think the genome's just a boring string of
letters, like reading the ones and zeros on your hard disk.
The genome is a storybook that's been edited for a couple of
billion years, and you could take it to bed, like
A Thousand and One Arabian Nights, and read a
different story, in the genome, every night.
Krulwich: If I could read each of the individual
letters, I might find the picture of what?
Lander: Well, of your children. This is what you pass
to your children. You know, people have known for 2,000
years that your kids look a lot like you. Well, it's because
you must pass them something, some instructions that give
them the eyes they have and the hair color they have and the
nose shape they do. And the only way you pass it to them is
in these sentences. That's it! It is hereditary.
Krulwich: So if I decode the two parts of each of
these ladders, I would know many things about my children,
things to be.
Lander: Well, in principle you would, the same way
that if you read all the ones and zeroes on your hard disk,
you would in principle know the Mozart symphony or the
Shakespeare play that you put on your hard disk. Now,
whether you could actually take the ones and zeroes and sing
the Mozart symphony from that, is another question. So
getting the letters out is one thing. Extracting their
meaning is another. The Human Genome Project is about
sitting there and getting the letters out. The next century
is about extracting all of the meaning out of the text, but
it's a pretty good text. It's worth the effort.
Krulwich: Getting the letters out has been described
as finding the blueprint of a human being, finding a manual
for a human being, finding the code of a human being. What's
your metaphor?
Lander: Oh, golly, gee, I mean -- I think this is
very much like in chemistry, the way the chemists describe
all of matter in terms of elements that they put into a
periodic table.
Krulwich: Right.
Lander: I think this is kind of biology's periodic
table. Everything that gets made in your body, whether it's,
you know, carotene in your hair or collagen in your skin or
hemoglobin in your blood, is specified by an instruction
here. This is basically a parts list. Blueprints and all
these fancy -- it's just a parts list. It's a parts list
with a lot of parts.
If you take an airplane, a Boeing 777, I think it has like
100,000 parts. If I gave you a parts list for the Boeing
777, in one sense you'd know a lot. You'd know 100,000
components that have got to be there, screws and wires and
the rudders and things like that. On the other hand, I bet
you wouldn't know how to put it together. And I bet you
wouldn't know why it flies.
Well, we're in the same boat. We now have a parts list.
That's what the Human Genome Project is about is getting a
parts list. If you want to understand the plane, you have to
have the parts list, but that's not enough to understand why
it flies. Of course, you'd be crazy not to start with the
parts list. So we figured that for the next century of
medical work, we'd better get the parts list and so
everybody rolled up their sleeves and decided we could work
together and get a parts list.
Krulwich: Before we go to how we do that, let me just
give you what I guess is one advantage. If I discover that
some human being is sick, and I suspect that the sickness
comes from some genetic trait, I guess I could ask and ask
and ask this molecule, "What's wrong with my kid? What's
wrong with my kid? What's wrong with my kid?" But the fact
that it's a molecule with a beginning and an end means that
whatever the mistake is it's somewhere in this molecule.
Lander: That's what's so important about this being
like a periodic table. When the chemists try to go figure
something out, they know there's only 100 elements or so,
and whatever you're trying to explain about matter, you've
got to explain in terms of those 100 elements -- oxygen,
hydrogen, etc.
What's now happening in biology is we know that whatever you
want to explain about heredity it's got to be in the three
billion letters specifying maybe 30,000 genes or so. In the
past you could always say, "Well, the cause is something we
haven't discovered yet." Not anymore. There isn't a
something we haven't discovered yet in genome form, or there
won't be very soon, and so it's a sea change in science to
know that you're explaining cancer or you're explaining
brain degeneration that's inherited, whatever you're
explaining, you only have 30,000 explanations to use and
maybe their combinations.
Everybody looks for the genome and thinks, "Ah! We're going
to cure everything." No. It doesn't mean we're going to cure
everything. It means for the first time we stand a fighting
chance of explaining the causes of things and getting
understanding about how it works. And then sometimes we'll
be able to cure it by the understanding. It's just that up
to now we've been trying to do it in utter ignorance about
most of the parts.
Krulwich: Most people think that this project has to
do with getting sick, that is, you're going to discover the
gene that causes blindness and the gene that causes deafness
and the genes that cause cancer and the genes that cause
these terrible things. But aren't we also trying to figure
out the gene that make you just a bit different from me, so
we could discover the chemistry of difference? Or is that
not the issue?
Lander: We want to understand what makes a human
being tick. Sometimes we study differences between people,
and the best way to find out what's wrong common to all of
us. By figuring out why I'm taller than someone who is
shorter, we can figure out the common mechanism that
controls bone growth, for example. And that mechanism is
useful to everybody, so in some sense all this focus on
difference is not really about classifying people by their
differences, it's that differences are our best way in to
the biological mechanisms that are the same in all of us.
We can only study those mechanisms when we see a difference
in them, because that's our clue to know that the mechanism
is there. If we were all exactly the same height, we
wouldn't think much about the mechanism that controls
height, but because we see a lot of difference in height,
we're clued in to the fact that there are mechanisms at work
that make some of us taller than others, and we can study
those.
Krulwich: How will we know the difference that genes
make and the difference that environment makes? For example,
if we're looking for cancer-causing agents, and we go to
Finland, we might say after rigorous study of the people of
Finland that everybody who gets cancer there seems to have a
problem, here, here, and here. But then when we go to
Tanzania, we may discover that everybody who gets cancer in
Tanzania has a problem here the same, but now here and here.
Then what have we learned?
Lander: Well, the first thing to say is that the
differences around the world are much less than you think,
even though we're six billion people scattered around the
whole world. In point of fact, the entire human species
traces back a mere 5,000 generations ago, to a small
population in Africa. All of us descend from a population of
10- or 20- or 30,000 people in Africa about 100,000 years
ago. And it means that, because 5,000 generations is such a
short time from the point of view of genetic evolution, the
variance present in Africa and the variance present in Asia
and the variance present in northern Europe are largely the
same. There's not that much variation.
Krulwich: How close are we? I know that we are very
close to chimpanzees for example.
Lander: Any two chimps in Africa are five times more
different than any two humans on this globe.
Krulwich: Any two chimps?
Lander: Any two chimps in Africa have five times more
genetic variation than two random humans on this globe. You
think the chimps all look the same; believe me, they think
we all look the same.
Krulwich: And on paper, anyway, we are more of the
same to each other?
Lander: We are much more similar to each other than
chimps in Africa are.
Krulwich: Because we are such a young species?
Lander: We are a small species that has grown large
in the blink of an eye. We tend to forget that; we like to
focus on our differences, but our differences are a pretty
trivial portion of our genome. And the distribution of those
differences across the globe is actually much flatter than
we think about, much more uniform. If we take any village
anywhere in the world, it has roughly 80 percent of all the
genetic variation found anywhere in the world, just within
that village. We just like to have wars and things about how
different we all look, but compared to most species, we're
not very different.
Krulwich: If we go down that list of 3.1 billion
chemical constituents.
Lander: Yup.
Krulwich: Do all of them manufacture something that
makes us?
Lander: No. No. Actually most of the DNA letters in
your genome don't manufacture any proteins that do anything
in your body. Indeed, only a few percent are probably needed
to manufacture all the proteins in your body.
Krulwich: Why do you mention proteins?
Lander: Genes contain instructions for making things,
and almost always the things that they contain the
instructions for are proteins like carotene in your hair or
collagen in your skin or hemoglobin in your blood.
Krulwich: Huh! So genes create proteins and proteins
build us.
Lander: Proteins do the work. Genes are the
instruction sets for those proteins. Actually only a few
percent of all of your DNA is devoted to writing down the
instructions for those proteins.
Krulwich: Say if five percent makes the proteins,
what does the other 95 percent do?
Lander: Well, at least 50 percent of it consists of
selfish DNA elements.
Krulwich: Of what?
Lander: Selfish DNA elements, that is to say chunks
of DNA that know how to reproduce themselves. And they just
live in your chromosomes, so you think it's your genome,
but, in fact, more than half of your genome consists of
elements that know how to copy and move themselves around or
fossils of such elements.
Krulwich: Are they my predecessors up the
genealogical tree?
Lander: No. No.
Krulwich: Are they a snake that I formally was?
Lander: Not at all. They couldn't care less about the
snake or anything like that. They've been around for about
one and a half billion years, and they're little DNA
segments. There's one that's about 6,000 letters long. It
knows how to copy itself into RNA and move itself to
someplace else in your DNA, and when it gets there, it knows
how to copy itself and move itself someplace else. It
doesn't do anything useful for you, and, thank you, it isn't
interested in doing anything useful for you.
Krulwich: Is this some billiard ball that I've got
wandering around inside my genome?
Lander: Well, it's something like that, yes. You've
got these things hopping around your genome that get called
"transposable elements," and they look out for themselves.
They're like little parasites in your genome.
Krulwich: Okay. So I've got letters that do stuff
that makes me.
Lander: Right.
Krulwich: I've got wandering around stuff that
doesn't do anything. It just seems to have the habit of
living in me.
Lander: It does a lot for itself. It largely thinks
your genes are just there to help propagate it.
Krulwich: So I've got five percent that's making me,
a lot of stuff that's jumping around and then trash or
junk?
Lander: It's junk. You keep it around, because it
turns out that occasionally the junk in your genome turns
out to be very handy. Every once in a while a piece of junk
that lands in your genome serves a useful purpose and gets
used by the body. A great example is your immune system.
Your immune system does a very cute trick where it can
rearrange pieces of DNA to make antibodies to recognize
anything. You know where it learns how to do that?
Krulwich: Where?
Lander: It's a piece of junk that landed in the
genome about 400 million years ago that carried with it an
enzyme for hopping around. Your body took over that enzyme
and used it to rearrange genes to make antibodies. So every
once in a while we get quite a nice gift from this junk.
Krulwich: So you make no apologies for spending all
those long machine hours writing down the names and letters
of all that stuff.
Lander: Indeed, many people argued in the 1980's that
we should just spend the money, sequencing the important
stuff. The problem is the important stuff is scattered about
in the sequence. We could have spent 20 times as much money,
just finding the important stuff and sequencing it, as
sequencing everything.
It would be like, you know, going through a library and, you
know, reading the books or something and trying to -- "I'm
just going to read the interesting sentences." Well, it's
really tough when you've got a novel to just read the
interesting sentences or the interesting paragraphs without
reading the novel.
Now somebody will invent a very clever way to do that, but
nobody has yet, and so the most efficient way was to sit
there and read the whole thing. It turned out to be not that
expensive, and every one of those letters helps us
understand human biology. We can actually learn a lot from
the junk. You want a great example?
Krulwich: Yeah.
Lander: The gene that causes Duchenne muscular
dystrophy when it's mutated, that gene is spread out over
two million letters of DNA, of which only 16,000 matter.
Krulwich: Wow! So the useful part is scattered in the
junky part?
Lander: The cell copies and copies and copies two
million letters, and then it splices together, throwing out
almost all two million letters to save only 16,000 letters
to make that protein.
Krulwich: But how do you know of all these rungs
which is the stuff that's doing stuff for you?
Lander: That's what we're engaged in right now.
That's called interpreting the sequence, annotating the
sequence. You've got all the letters. It actually doesn't
come color-coded; it doesn't come with little special marks
saying "This is important." You have to sit there with all
the A's, T's, C's and G's and figure out which bits matter.
And so we have elaborate computer programs to try to figure
out which fits have the potential to code for a protein in
your body.
Krulwich: I get the sense that everybody is getting
out of the gene business and suddenly going into this new
business I hear about called the protein business. There's
even a new name, instead of the genome, I'm hearing this
other name, which I don't--
Lander: The proteome.
Krulwich: The proteome, what is that?
Lander: Well, the genome is the collection of all
your genes and DNA, the proteome is the collection of all of
your proteins. See what's happening is we're realizing -- I
think we always realized that if we wanted to understand
life, we had to start systematically at the bottom and get
all the building blocks. The first building blocks are the
DNA letters, from them we can infer the genes. From the
genes, we can infer the protein products that they make to
do all the work of your cell.
Then we've got to understand what each of those proteins
does, what its shape is. How they interact with each other,
and how they make kind of circuits and connections with each
other. So in some sense, this is just the beginning of a
very comprehensive systematic program to understand all the
components and how they all connect with each other.
Krulwich: How many proteins do we have?
Lander: Well, it's very interesting. One gene can
make multiple proteins. It turns out that the gene makes a
message, but the message can be spliced up in different
ways, and so a gene might make three proteins or four
proteins, and then that protein can get modified. There
could be other proteins that stick some phosphate group on
it or two phosphate groups.
And, in fact, all of these modifications to the proteins
could make them function differently. So, while you might
only have say, 30,000 genes, you could have 100,000 distinct
proteins, and when you're done putting all the different
modifications on them, there might be a million of them.
It's scary talk.
Krulwich: The proteome project could then last a lot
longer than the genome project?
Lander: Oh, no. I doubt it, because, I mean, the
difference between 30,000 and 100,000 is only a factor of
three. The great thing about this explosive period of
science is that these big numbers, they sound scary, and
then within five years some bright student figures out a way
to say, "Oh, yeah, well, what's a factor of five, and what's
a factor of 10 here and there?" It wasn't very long ago that
sequencing a couple hundred letters of DNA was enough to get
a whole Ph.D. thesis.
Krulwich: Now a robot does it?
Lander: A robot does an awful lot more than that in
the course of a day. There's just this incredibly explosive
learning curve about how to work with this material.
Krulwich: Before I leave the subject of proteins, one
last question.
Lander: Yeah.
Krulwich: When I think about proteins, if I'm trying
to think strategically -- I think if I get sick that may
mean that my proteins are causing me harm, because the bad
gene created a bad protein?
Lander: Yup.
Krulwich: So are pharmaceutical companies now going
to be trying to figure out how to maybe not get down and
rearrange the genes, but maybe just deal with the
protein?
Lander: Most drugs on the market today affect the
protein, not the gene. The gene is the instruction for
making this component. The drug you take, the pill you pop,
usually interacts with the protein, to slow down its
function, speed up its function. That's what's really going
on. Very few drugs interact with genes.
Krulwich: So if I had a horrible genetic disease,
like Huntington's, maybe someone will figure out a way to
cure the protein part of my disease?
Lander: For Huntington's disease we know that the
problem is the gene is defective in a way that it makes a
protein that is a big long extra chunk of it that's very
sticky, and it sticks to other stuff and gums up the works.
The Holy Grail for Huntington's disease is to make a drug
that would block this sticky protein from interacting with
other things.
Krulwich: How about cystic fibrosis?
Lander: For cystic fibrosis, it's a little trickier.
There you have a protein that can't perform its job. It
can't transport chloride across itself. You've got to make a
drug there that somehow would restore its function. That's
not very easy. When you have a broken part, it's hard to add
a gene that will restore its function. So there people are
talking about somehow spraying a virus into your lungs that
will carry with it a new good copy of the cystic fibrosis
gene, for example. Those are the kind of ideas people
have.
Krulwich: And, last, I get the sense that the genome
project was largely a way of discovering a long chain of
things? When I think about the proteins and the proteome
project, for some reason I think about origami. I don't know
why, but when I read things, I hear that you're folding and
unfolding and bending and twisting. What is that about?
Lander: The genome project was a piece of cake
compared to most other things, because genetic information
is linear. It goes in a simple line up and down the
chromosome. Once you start talking about the
three-dimensional shapes into which protein changed and can
fold, and how they can speak to each other in many different
ways to do things, or the ways in which cells can interact
like wiring up in your brain, you're not in a
one-dimensional problem anymore. You're not in Kansas
anymore. You're way off.
Krulwich: You need geometry--
Lander: You need complicated geometry and diffusion.
That's why it's not a quick shot to just go from the genome
to curing something. The work of the next century will be to
take the simple linear sequence and see if we can build
models that explain these complex three-dimensional
interactions and the kind of conceptual circuits of A
tickles B, tickles C, tickles D at the molecular level and
figure out, you know, which proteins to goose to fix some
disease.
Krulwich: Here's one of the big astonishments, to me.
We are related, more closely related, apparently, to
creatures, than I had ever imagined. You too?
Lander: We are all incredibly related to
creatures.
Krulwich: But a chimpanzee, that I could figure. A
big ape, that I could figure. Eighty to eighty-five per cent
of the genes in a mouse are in one.
Lander: More than that.
Krulwich: More than that.
Lander: More than that. I'd say, it's 98 percent of
the genes in the mouse, you can find clear matches in a
human. There's not a lot of difference between you and a
mouse.
Krulwich: What does that mean exactly? If you took
off the skin of a mouse, went right in and looked at the
cell, would you just see the same exact stuff, in the same
exact order that you see in me?
Lander: If you looked inside the body of a mouse, you
see lungs, you see hearts, you see pancreases.
Krulwich: But let's get cellular.
Lander: But wait a second. All of the genes that have
to direct the arrangement of those organs have to be the
same. The only difference is, a few genes might control some
size. There might be a little variation of the exact shape
of things. But those are small compared to building all
these complex structures. Pretty much every structure we
have a mouse has. And so most of the genes you're going to
need to build it are the same. It's like two kinds of
airplanes.
Krulwich: But we are so much bigger, smarter. We make
music, they squeak. We walk around, we go to school. There
has, as far as I know, never been a mouse school.
Lander: Yeah.
Krulwich: Therefore, how could they have as many
genes as we do and yet we be so much, excuse the expression,
better.
Lander: Well, it's a somewhat self-centered view to
think we're better, but we're certainly different, right? I
think the main take-home message from this is that the
differences in the human from many other organisms may
actually be small differences of degree that then have
gotten amplified.
See, we do all sorts of things that a chimp doesn't do. And
that's not because we invented a lot more genes. It may be
for something as simple as the little genetic controls that
cause the number of nerve endings made them double in the
human, for example. That could lead to lots more connections
without lots more genes. It might be just tweaking the dials
a little bit ends up producing quite qualitatively different
behavior.
Krulwich: So you could look deep into the eyes of a
great ape or a chimpanzee and there is something vaguely
familiar about that.
Lander: Vaguely familiar? It's virtual identical. To
any other organism on this Earth, they'd have a hard time
telling you apart from the great ape.
Krulwich: And yet what's the difference between us
may be simply that our genes turned on some dial so we got
ten times more brain cells than they got, or something like
that?
Lander: Or, probably more likely, that brain
development slowed down in humans so that more of it could
be affected by environment and experience and childhood. In
many ways, it said that the human brain development is more
like a baby chimpanzee, a neonatal chimpanzee, and that we
are therefore open to more learning and more shaping by
environment for much longer in our development. That may be
the secret to it, that we actually fossilize our brains into
the adult form much more slowly.
Krulwich: Which means that the difference between us
and the big ape is not the genes that we don't have
together, it's... What is it, then?
Lander: It may be the controls on these genes. It may
be simply how soon the gene is turned up or off or what
level it's turned on to. It might be two letters of DNA that
affect how actively the gene is transcribed in the cell.
Those are the sort of small variations on the theme that
could make a huge difference in how an organism turns
out.
Krulwich: Let me get back to relationships. If we are
almost identical to mice and 80 percent of the genes in the
cow are in us, and 61 percent of the genes in a fruit fly
are in us, and -- this is the one that gets me -- 50 percent
of the genes in a banana are in us?
Lander: How different are you from a banana?
Krulwich: I feel -- and I feel I can this with some
authority -- very different from a banana.
Lander: You may feel different from a banana--
Krulwich: I eat a banana, but I have never--
Lander: Look, you've got cells, you've got to make
those cells divide. All the machinery for replicating your
DNA, all the machinery for controlling the cell cycle, the
cell surface, for making nutrients -- all that's the same in
you and a banana.
Krulwich: Wait. You honestly feel, when you came to
this subject, a genetic relationship to the banana that was
this strong?
Lander: Take baker's yeast. Baker's yeast we're
related to, one and a half billion years ago. You can take
genes out of a baker's yeast that controlled the basic cell
processes like cell division, and you can put them into a
human cell, and they function. And, in fact, they're the
very genes that cause cancer in us, because they affect cell
division and they affect cell division in yeast.
Krulwich: Wait. In other words, if you had a person
who was sick in a particular way -- let's say his cells
weren't breaking down properly or multiplying properly. You
could take a healthy gene from a yeast, stick it in the
person, and make the human feel better, fix the human?
Lander: It would be unethical to do it that way, but
we do the reverse all the time. You can take the gene out of
the human, stick it into the yeast, to make it play the same
role as its evolutionary relative, one and a half billion
years ago. And it works. Presumably, it works in the other
direction, too, although we don't do it on patients.
Krulwich: So you were saying, then, that you could
take a yeast that wasn't feeling too good and then go into
my cell and take a piece of me, a healthy chunk of me, and
fix the yeast?
Lander: Well, if there was a defect in how the
yeast's cell division occurred, your gene would work just
fine in the yeast, and people do that experiment all the
time. We can do gene therapy to cure a sick yeast using a
human gene. Presumably, it works the other way, too,
although we don't do it, because it's not ethical. But even
after one and a half billion years of evolutionary
separation, the parts are were still interchangeable for
lots of these genes.
Krulwich: Now, does that mean--I just want to make
sure if I understand this right. Does that mean when you
look through those things that all the C's and the A's and
the T's and the G's, are you seeing the exact same letter
sequences in the exact same alignment? When you look at the
yeast and you look at the person, is it C-C-C-A-T-T?
Lander: It's eerie. The gene sequence is almost
identical. There are some genes, like ubiquition, that's 97
percent identical between humans and yeast, even after a
billion years of evolution.
Krulwich: Well, with a name like that, it's got to
be.
Lander: Well, yeah. But then there are other genes
where, when you look at other genes, you can still see, for
example, that out of the protein sequence, oh, 60 percent of
the amino acids in the protein are exactly the same, and
maybe 20 percent more are at least similar chemically. And
there's no doubt it's the same object, even though it's
varied some over one and a half billion years.
Krulwich: Now, is this why you can go to a pig, a big
fat pig, and get the pig insulin out of the pig and give it
to a human diabetic? I mean, are we talking about the same
thing?
Lander: Pig insulin, human insulin, it's doing the
same thing: it's interacting with the same receptor on the
surface, an insulin receptor making the same kind of
molecular signal. It's the same thing. Now, there're slight
variations in pig insulin and human insulin that could lead
to problems of immunological cross-reaction, but that's
usually about details, small details in the insulin. The
function of the pig insulin is virtually identical to the
function of the human insulin.
Krulwich: So when you say interchangeable parts,
that's actually become a business: People take a product
from a pig and give it to a sick human, and the sick human
uses the product and gets better, feels better.
Lander: Although these days we do it by cloning
techniques where we can actually get a bacteria to produce
the human product, and that's even safer still. But you've
got to understand that, deep down, the fundamental
mechanisms of life were worked out only once on this planet
and have gotten reused in every organism on the planet.
Evolution doesn't go reinvent something when it doesn't have
to.
Krulwich: Well, is it a headline that we are more
closely related to each-- By the way, before I ask that, how
about plants? Let's suppose I had like a mustard seed, I
don't know, a fern -- I'm trying to think as distant from
myself as I can. So I walk up to a fern and I say Hello.
What part of the fern has already got more or less pieces of
me in it?
Lander: Oh, golly. Mostly what you share in common
with a plant are the basic genes that run a cell. Because
while you look very different from a plant, standing back,
the closer and closer you get to a cell, the more you see
bag with stuff in it and a nucleus. And most of those basic
functions are the same. I suppose if you look at two
different automobiles driving on the street, they may look
very different, but if you look under the hood the engines
look remarkably similar. And I think that's true for most
cells, whether it's in plants or animals -- that, under the
hood, the engine is pretty similar.
Krulwich: And that seems to be a major discovery of
this project, so far.
Lander: Well, this has been a discovery, I think,
that's been dawning on us with genome sequencing over the
last couple of years, and the human sequence has made very
clear that we are not separate and different in any way
there. We are very much partaking of that same bag of tricks
that evolution's been using to make organisms all over this
planet.
Krulwich: Let me go to the next headline. Fruit
flies, as much as you might admire them, are small and
foreign like creatures to moi. Yet I discover that the
number of genes in a fruit fly is only about half the number
of genes in me.
Lander: Yeah. That's really bothersome to many
people, that we only have about twice as many genes as a
fruit fly. Because we really like to think of ourselves as a
lot more than twice as complex as a fruit fly.
Krulwich: Don't you?
Lander: I certainly like to think of myself that way.
And so it raises two questions: Are we really more complex?
Well, I think so. I think we've got lots more different
tissue types, cell types, interactions in our body.
Krulwich: Well, let's let things speak for
themselves. You show me the fruit fly that can compose like
Mozart, and then I'll obviously--
Lander: Show you the human that can fly, right?
Krulwich: All right.
Lander: We all have our talents, right?
Krulwich: Yes. Anyway, but you feel somewhat
diminished, don't you, a little bit, at least at first
blush, by this?
Lander: Well, at first blush the reaction is to be a
little insulted that you only have twice as many genes as a
fruit fly. But when you begin to think about it, you realize
that complexity may not just be in the number of genes.
Twice as many genes may translate into four times or eight
times or 16 times as much complexity. And we can see from
the genome sequences -- this is really one of the most
exciting things from the genome sequences -- ways in which
our own genes are more complex.
Krulwich: So, the difference, then, the possible
difference, between a fruit fly and a human is that the
number of different splices and restitchings in a human is
just higher?
Lander: It seems we've got twice as many. So one of
the levels at which we're more complex than a fly is that a
typical gene might get spliced and diced up into twice as
many products as in a fruit fly. That's one level of
complexity.
Krulwich: So twice as many proteins are being
produced by the same gene in a human than in a fruit fly.
Lander: That's one level of complexity. But there's
more to it. When we actually look at the proteins in the
human, proteins are made out of building blocks that we call
modules. Humans haven't invented a lot of new modules I've
got to say. Most of our modules are the same as in the fruit
flies. But we put them together in more combinations. We
call those architectures. We have more different
architectures for our proteins than a fruit fly does. And I
think what that does is it lets our proteins interact in
lots more ways. We can make lots more complex tinker toys
out of these parts, because we've combined those modules in
twice or three times as many combinations.
Krulwich: So starting with the same raw ingredients,
the fruit fly goes... But the human, by somehow or other
being able to arrange all the parts in many different ways,
can produce melodies perhaps.
Lander: Yes, although we're not that good at hearing
the melodies yet. One of the exciting things about reading
the genome sequence now is we're getting a glimpse at that
complexity of the parts and how it's a symphony rather than
a simple tune. But it's not that easy to just read the sheet
music there and hear the symphony that's coming out of
it.
Krulwich: But is a metaphor okay? Should we think of
the fruit fly somewhat as a creature that's learning to play
chopsticks, and think of the human as a creature whose genes
have learned to play Mozart?
Lander: Yeah. That's probably a bit extreme. I mean,
it's pretty fancy making a fruit fly, too. I'd say it's way
past chopsticks, and we may not quite be Mozart, but there's
no doubt that we have more lines of music coming in
together, in a much more complex melody that's coming out of
it.
Krulwich: And so the bottom line question is, What is
it that makes a human being human? Since if you're sitting
next to a fruit fly and he seems to have almost the same
number of ingredients that you do, the difference, the thing
that makes us human, is?
Lander: Well, the one thing that distinguishes human
beings from all other organisms on this planet is they're
the only organisms that worry about what distinguishes them
from all other organisms on this planet. Other than
that--
Krulwich: I was hoping for some more architectural
response.
Lander: I understand, but every other attempt that
people have to say why humans are distinctive usually fails
when you look really hard. But we're the only ones that
worry about that question.
Krulwich: But, if I hadn't forced you, you'd say it
had something to do with the human being's genes able to
produce more proteins and more variation among the
proteins.
Lander: Now, be careful. This isn't what makes humans
different. This is what makes vertebrates different. Because
whatever you're claiming for the human at the level of its
genomic complexity, you've got to claim for the mouse and
the dolphin. So this is not distinctively human. If you ask,
"What's distinctively human about the human genome, compared
to, say, a chimpanzee?" We haven't a clue. In fact, if I
gave you the three billion letters of the chimp, and the
three billion letters of the human, and I didn't tell you
which was which, without cheating by peeking at the right
answer, no scientist on Earth could tell you which was human
and which was chimp.
Krulwich: But why? Isn't there somewhere you look for
"hair all over" or "big face?"
Lander: Of course, somewhere it says, "Hair all over
the body" in the chimp genome. But we don't know how to read
that. It's there, but we don't know how to know that
somewhere it said, turn off the hair on most of the skin of
the body. That's our level of ignorance about this.
This is what the next century is about. See, we have the
text, for the first time. It's incredibly exciting. We can
see sentences and nouns and verbs all over the place. We
haven't got the plot from all that. We've just barely got
the text, we know bits of the language. We don't yet know,
subtly, how -- it's embarrassing. I give you a cat and a
dog, the two genomes. It wouldn't be easy to tell which is
which. We can't tell.
Krulwich: Let me ask you about another important
difference. Imagine, if you will, a Sumo wrestler on the one
hand, and one of those Sports Illustrated bathing
suit beauties on the other -- two humans of strikingly
different physique. What is the genetic difference between
the fat guy and the skinny girl?
Lander: The genetic difference between any two
people, whether it's a Sumo wrestler or a
Sports Illustrated bathing suit model -- one-tenth of
a percent. Those two, and any two people on this planet, are
99.9 percent identical at the DNA level. It's only one
letter in 1,000 difference.
Krulwich: So that one letter in 1,000 makes him look
this way and her look that way?
Lander: Well, of course, him and her has a little to
do with X and Y chromosomes, so we've go to take that out of
the equation. But the picture I always like to show is Wilt
Chamberlain, basketball player, and Willie Shoemaker,
jockey. Both men, 99.9 percent identical, but one of them is
almost twice as tall as the other. What's going on? Well, it
tells us that, first, as a species, we are very, very
closely related, because any two humans being 99.9 percent
identical means that we're much more closely related than
any two chimpanzees in Africa.
Krulwich: But if you look at an Icelander, that
Icelander has such a different physique than an African.
Lander: How many genes does it take to change a
physique?
Krulwich: How many genes does it take to
change a physique?
Lander: Well, we don't know, but we know there's not
a lot of gene differences. So maybe it only takes four or
five genes to affect skin color. That's certainly the sort
of estimates people have made. And height. Oh, okay, maybe
there'll be some tweaking of 15 or 20 genes or something.
But when you add it all up, it's not that much.
Now, of course, the implications of this is small
differences in the genetic code can have big consequences
for the appearance or the disease risk. I mean, there's a
single letter change, out of three billion letters, that can
increase your risk of Alzheimer's disease by 40-fold. So,
little differences -- spelling counts.
Krulwich: I don't quite understand. If you are
looking at a black woman and you're looking at a white
woman, there's a drastic difference to your eye. Are you
saying that there is--
Lander: That's accounted for by a smallish number of
genes, but that most of the genetic variations that are
going on within those populations are common to both
populations.
Krulwich: But from the gene's point of view, the two
people who look so different to your eye are remarkably
similar, as far as the genes are concerned.
Lander: Remarkably similar, and they both might be
suffering from the same predisposition to diabetes due to
the same genetic variation, for example. They might be
suffering from other kinds of conditions that are exactly
the same DNA spelling difference. And it's only if you want
to focus on those things that are just skin deep that you
can say, "Aha, the genes distribute differently in the two
populations." Otherwise, for most other things, the genes
are continuously present across all these populations.
So race is not a very helpful category to a geneticist,
because it's focusing on a fairly small number of genes that
describe appearance. But if we're talking about physiology,
if we're talking about the 30,000 genes that run the human
symphony, that's a tapestry that weaves through every
population. That's why geneticists really don't think race
is a terribly helpful concept.
Krulwich: And what about you and Arthur, your
brother? What's the difference between you and him?
Lander: He's a better cook, far better cook.
Krulwich: We're talking genetically.
Lander: Oh, genetics.
Krulwich: You come from the same parents, you're
clearly not the same people.
Lander: Well, 50 percent of our genes are identical,
by descent. So the other 50 percent are as different as any
two people on this planet, so I suppose we're twice as close
as any other two people on this planet, because we're
brothers.
Krulwich: So that's what we think of it -- that, as
the closer you are in relationship, the more you have in
common, but there's this other whole category, called
everything else, which can vary.
Lander: Half of our chromosomes, we got exactly the
same copy for that region. The other half, it's as different
as you and me.
Krulwich: And identical twins?
Lander: Identical twins, it's 100 percent of the
chromosomes are the same. They are genetically identical.
Krulwich: But they don't feel identical at all.
Lander: I didn't say they're identical. They're
genetically identical. Whether or not you're identical,
well, that depends on your whole life experience, your whole
history. They're not identical people. But, at the genetic
level, the proteins are the same, the controls are the same.
And it just reminds us the outcomes can be quite
different.
Krulwich: I want to do one thing before we go to the
last category, about sex. Men have something to celebrate,
apparently. There is a headline that's good for guys. Tell
me the headline.
Lander: One of the cool things you can find by
reading the genome sequence is that the rate of mutation is
different in sperm than in eggs. You can actually see this
by reading the genome story, by looking at how quickly
certain things are mutating if they happen to be on the Y
chromosome versus on the X chromosome. And by measuring that
over 40 million years, we can find out that about twice as
much mutation is happening in sperm -- that is, in males
passing on their genes -- than in females. And that leads to
a wonderful battle of the sexes. The guys I know say, "Aha,
men are responsible for two-thirds of all evolutionary
progress."
But, of course, women looking at that picture are equally
well entitled to say the guys are responsible for two-thirds
of all the misery of genetic disease that occurs through
those mutations, too. Me, I'm going to be a conscientious
abstainer on this question.
Krulwich: Now when your group, the public group,
decided to survey all the DNA of a human being, which human
beings did you survey?
Lander: So the genome that we sequenced, in fact,
comes from about a dozen different people.
Krulwich: A dozen? Were they fat ones, skinny ones,
black ones, white ones?
Lander: We don't know who they come from, because, in
fact, what happened was--
Krulwich: You don't know who they come from?
Lander: No. Part of the rules was that we don't know
and they don't know. See, ads were put in the papers,
inviting people to sign up and donate DNA for the Human
Genome Project. But we got five or six times as many donors
as we were going to use.
Krulwich: What kind of ad? What sort of ad was it?
"Please come downtown and give us your blood," or "give us
your cheek"--
Lander: Yes, yes. "There's an opportunity to donate
DNA for a biomedical research project." And then people had
to receive a complete description of the project and sign an
informed consent document. The blood sample was taken. And
then--
Krulwich: What if a busload of very fat people came
up and all nominated themselves, and you had no skinnies?
Then you would have the human genome of the fat people.
Lander: Which differs by one tenth of a percent from
anybody else.
Krulwich: Well, you don't know that going in.
Lander: Oh, we do. We have a really good sense of
genetic variation. And it's not a lot.
Krulwich: Now wait, I'm suspicious here. How do you--
You said you got a mix, 10 or 12 people.
Lander: Yeah.
Krulwich: Were they a mix of-- did they come from,
some of them from Borneo and some from America and some
from--
Lander: So the genes from which most of the work was
done come from Buffalo, New York.
Krulwich: From Buffalo, New York?
Lander: Yes. It's mostly a guy from Buffalo and a
woman from Buffalo. But that's because the laboratory that
was making--
Krulwich: An anonymous couple from Buffalo?
Lander: They're not a couple. They've never met. And
we don't know who they are. So we got a lot of the
samples--
Krulwich: And they don't know who they are, except
that
they--
Lander: The laboratory that prepared the large DNA
libraries that were used was a laboratory in Buffalo. And so
they put an ad in the Buffalo newspapers, and they got
random volunteers from Buffalo, and they got about 20 of
them. They then erased all the labels and chose at random
this sample and that sample and that sample. So nobody knows
who they are. We don't have any links back to who they are,
and that's deliberate.
But then to define all the human variation on top of it, we
sequenced millions and millions of DNA segments from a
worldwide population of 24 people: Pacific Islanders,
Asians, Africans, Americans. And that defined more than
one-and-a-half million sites of genetic variation in the
chromosomes.
Krulwich: So you feel you have a pretty good sample
of humanity?
Lander: Oh, I think, about half of the common genetic
variation that exists in the human population is already
represented in that data base of DNA differences that we
found amongst people. And what it does is, it reinforces the
message of how these differences are interwoven through the
whole planet, through the whole population.
Krulwich: And how many other creatures are we
sequencing?
Lander: Oh, goodness, there's so much sequencing
going on today. In terms of large beasts, wow: vertebrates,
mice are being sequenced right now, rats are being
sequenced. Two different kinds of puffer fish, one zebra
fish, various different types of worms, flies, a couple
dozen fungi, bacteria, a couple more plants going on. I
mean, sequencing is such a great way to get a first look at
an organism. You'd be crazy not to do a little sequencing
first.
Krulwich: One of the sort of happy futures that we're
rolling towards is customization. Tell me a little bit about
what might be around the corner, in that way. Three people
have the same mistake, they go take the same medicine. Two
people get well, one doesn't. So what do you do for the
third guy?
Lander: Well, what we're coming to understand is that
three people who supposedly have the same disease really may
have it because of very different reasons. You know, we call
it all asthma, but it might be Asthma Type 1 and Asthma Type
2 and Asthma Type 3. And the medicines might work very
differently in those people, because you're trying to fix
something that's not broken in the third person, and not fix
the thing that is broken. Or you're giving someone a
medicine that's going to be broken down by their body in a
different way, maybe to something that's a toxic side
product. Or maybe it'll just get broken down four times as
fast, and can't do its job.
We have different physiologies. And understanding those
subtle differences in physiology, whether it's the cause of
the disease that's different or the reaction to the medicine
that's different, I think will be important in matching the
right drug to the right patient.
Krulwich: Well, in the same sense as there used to be
Pan-American and TWA and Eastern Airlines. They'd fly you
everywhere. And there was Grand Union, and there was the
A&P, and they would sell you all the food. And there was
NBC, CBS, and ABC -- those were the broadcasters. Now
medicine can narrow-cast.
Lander: Well, the hope is that medicine can
narrow-cast. Of course, you can't make it too narrow,
because it's pretty expensive to develop drugs. And if we
make it so narrow that you can't actually afford to run the
clinical trial, we're not going to get medicines, either. I
think the hope is that the broad category of asthma will
turn into four types of asthma, and that we'll be able to
develop drugs that have a much higher therapeutic index,
much higher ability to cure the disease in each of those
four cases than before when we were just trying to treat the
general symptoms that were in common, but not the causes
that were different.
Krulwich: So Hayden [a boy profiled in the NOVA
program "Cracking the Code of Life" who has Tay Sachs, a
fatal disease caused by a single-letter mutation], like all
human beings, has three point something billion chemicals
inside the DNA molecule, and one of the three billion--
Lander: One letter.
Krulwich: One letter.
Lander: One letter. It's I suppose understandable if
you think about screws in an airplane. There's an awful lot
of screws in an airplane that don't matter if you don't have
them in the right place. Maybe your seat back will be a
little loose or something. But if it happens to be a screw
on the propeller, it can matter a lot. There are some
positions that encode the information for unique proteins,
which you absolutely have to have. And if they're misspelled
you don't have this essential function, and you'll die.
Krulwich: Now that we have this sort of microscopic
view, do you have the sense that this is more unfair than we
had previously realized? It seems amazing to me that
something so slight could result in such a huge
difference.
Lander: Genetics is largely random. Every time your
DNA is copied usually the right letter is put in, but
there's some very small probability the wrong letter gets
stuck in, and it's utterly random. Every time a baby is
born, about 30 new mutations occur in the sperm and in the
egg, giving rise to that baby. It usually makes no
difference because these 30 new mutations occur in places
that don't matter. But sometimes they occur in places that
do matter, and there's no rhyme or reason and no fairness in
it. It's chance where they happen to occur. And so, no, it's
not fair.
Krulwich: The family says--and we asked them, you
know, "What should have happened in your case?" They say
quite simply, "Well, we should have tested." But they
weren't Jewish, or they weren't obviously in the risk
population. So they say, "We really should have tested." In
fact, everybody should test for everything, because then we
won't have situations like this. What are the consequences
of that logic?
Lander: Ideally we should understand everything that
could go wrong and be able to offer people the chance to
test for whatever they want to. We're nowhere near that
today. We don't understand all the roles of all the genes.
We don't understand which misspellings really matter. And we
also don't understand how to explain to people enough about
these choices for them to be able to make intelligent
decisions.
In some cases it's pretty clear. If you could know that
you're at a very high risk for having a baby with Tay Sachs,
I think almost everybody would choose to know. What if
you're offered the chance to find out whether your baby
might be of high risk for Alzheimer's disease when he or she
is 70? Would you want to know? What if that risk is only 50
percent? What if you could be offered a whole range of tests
for whether or not you might have not the usual one percent
risk for some kind of a cancer but a four percent risk for
that kind of cancer?
I don't know quite what to do with it. It might be relevant
information. It might be the case that it's sensible to
screen somebody twice as often if they've got a four percent
than a one percent risk. The challenge is going to be
two-fold. Understanding it as science and then understanding
it as people. How to deal with not certainties but
probabilities, relative risks. We have got a tremendous
amount of work to do both in the laboratory and with the
public to get to the point where we know how to deal with
this information and offer this information in a way that's
useful.
As a parent I just imagine what it would have been like if I
could have been offered a menu of 10,000 genetic tests to be
done. See, there are changes in many, many, many genes, and
many of them don't mean anything; they're just irrelevant
changes. But you could get back a menu with all of them.
Some of them might matter and we can't tell. There will be
tremendous anxiety in knowing and there will be tremendous
anxiety in not knowing. You might feel irresponsible if you
said, "I'm not going to find out." And you would feel
tremendous regret if something happened. But you might also
feel just tremendous pressure if you found out and doctors
couldn't explain to you whether it mattered or not.
We have opened a box here that has got a huge amount of
valuable information. It is the key for understanding
disease and in the long run to curing disease. But having
opened it, we're also going to be very uncomfortable with
that information for some time to come. It would be immoral
not to get this information, because in it is the secret of
cures. But it's going to be very uncomfortable dealing with
some of this information for the course of the next
century.
We obviously want to know about those things because by
knowing the mechanism for breast cancer or colon cancer or
Alzheimer's, pharmaceutical companies can try to work on
cures. They can try to work on a drug that will slow down
the problem or prevent the problem. So we want that
knowledge to fashion a cure, but with it comes a certain
cloud of uncertainty that can hang, and every person has got
to decide, "Do I want to find out about this uncertainty and
that uncertainty?"
Right now maybe we only have 10 or 12 uncertainties we can
bestow upon people. But fairly soon we may be able to offer
hundreds of uncertainties, half which you can do something
about, have of which you can't.
The really great challenge for society is how we're going to
stand by each other, how we're going to say we all face
exactly that same problem of having potential knowledge
about our genomes, but the potential knowledge is different
for each of us. Will we unite around the idea that we all
are largely facing the same set of issues? Or will we split
apart into those people who have this risk, that risk?
I worry a great deal about whether we're going to go down a
path where we use this genetic information to classify
people, insure them differently, separate people, or instead
to unite people by saying, contrary to what they used to
say, "There's no perfect genome. None off us is particularly
better or more normal. We all have a wide range of
variations. Those variations make us spectacularly rich as a
species, as in a population. But they also give us each our
own particular problems." I think the biggest choice ahead
is how we're all going to come to understand the ways in
which we're genetically all the same and genetically all
different.
Krulwich: Last on this one, I guess I mentioned
Justin, who is the son [who also figures in the NOVA
program, and whose genetic heritage predisposes him to
potentially developing a certain disease later in life)].
His way of handling it is to say, "I just don't want to
think about it right now." "I just don't want to think about
it right now" seems to me a perfectly acceptable position,
but it might be one of the hardest ones to have.
Lander: Oh, yeah. Saying that you don't want to think
about a problem right now is a perfectly valid response. If
you really were mindful of all the potential problems you
could be completely paralyzed by worrying about
everything.
Sometimes the happiest life might be lived by just saying,
"Whatever happens will happen. I'm going to get everything I
can out of life and I'm not going to worry about it." The
hard part is where there are tests and diagnostics and
therapies that would let you change your risk. If we're
talking about something that you can't affect -- well, I
don't go out and find out my risk for Alzheimer's disease. I
don't want to know because there's nothing I can do; it will
just make me worry or it will make me very depressed if I
were to get bad news.
But if I were to find out I was at special risk for colon
cancer I would really want to know because I really could do
something about cutting that risk by twofold or fourfold or
tenfold. That's the hard part, is where sticking your head
in the sand really does come back to hurt you. At the moment
there are a limited number of cases where genetic knowledge
can be translated into medical action, but that will
probably increase with time.
Krulwich: And my second last question for this whole
shebang has to do with the power of genes. I think a lot of
people, particularly in a program that is going one to two
hours, get the impression that genes are our destiny to some
degree. You live with them and study them all the time. But
how fragile are all these predictions? Well, you have this
gene, then consequently--
Lander: People often have this sense of genetic
determinism -- that they're nothing but their genes, that
their genes contain their destiny written in the DNA. This
is nonsense. We know that there is a tremendous influence of
environment, of society, on outcome.
If you just think about the fact that the human gene pool
hasn't significantly changed in the last 5,000 years, and
you notice how much society has changed and opportunity has
changed, you realize that our genes really can't determine
things. They can be influences, but for the longest time
people said, "Well, women are incapable of doing something
biologically," or "Eastern Europeans aren't smart enough for
et cetera, et cetera." People looked to the genome to
justify their prejudices about what people could or couldn't
do.
But when we look at it there is a huge range of what human
societies have done, how they have been organized, what
opportunities people have had. That whole range is
encompassed within our genome. If that's the amount of
limitation in our genome that's okay; I'll live with
that.
Krulwich: Do you have any sense, any spiritual sense,
that what you've studied reflects anything that isn't on the
page?
Lander: Evolution is a pretty mysterious process. It
works by randomness and then selection. And I think we
tremendously underestimate the power of random
experimentation. You think, oh, if I vary things, how could
I ever get anything sensible out of it? And when you look at
the genome and you see the evidence of churning and mixing
and variation and duplication, you realize that this
completely undirected evolutionary force of variation
generation is incredibly powerful at invention, probably
more powerful than design.
No committee of engineers getting together, no matter how
smart, would have come up with a human being. And yet
evolution, by tinkering and getting it wrong most of the
time, but occasionally right, came up with a human being.
It's a pretty awesome process. We don't fully understand how
it works. But it is really humbling to look at a genome and
see what that slow and steady process of incremental
improvement has wrought.
Krulwich: So if God is designing into this system, He
may or She may or It may have designed the evolutionary
process, but there's nothing that you have seen beyond the
evolutionary process from your recent work?
Lander: The genome is awe-inspiring, but what the
basis of that awe is, we can't tell from that. We can see a
remarkable history of experimentation, of variation. But a
lot of it looks like it's random churning and just saving a
couple of good things that worked. We can't see more than
that in that. One of the great things that--
Krulwich: You save a couple of good things and you
save a couple of good things, and it all adds up.
Lander: That's what they tell you, right? A little
savings here, a little savings there -- it sort of adds up.
Well, there must be greater themes than that, because
evolution seems to have found ways to invent efficiently.
See, when it wants to make a new gene, it doesn't start from
scratch. Maybe back in the primordial ooze it would start
from scratch, but then you had a lot of time to work things
out.
It seems, by looking at the human genome, that when
evolution needs a new gene, it waits for some existing gene
to get randomly copied and then to slightly work on it. You
build out of existing parts. I think the secret of evolution
is that the genetic churning mechanism lets us make theme
and variation and theme and variation. And it turns out to
be much more powerful than we ever imagined to just make
small variations on the theme. You get from a couple little
circuits to us.
Krulwich: So your recent emersion in this stuff just
makes you think that Darwin was smarter even than he even
imagined?
Lander: This gives you a tremendous respect for life.
It gives you respect for the complexity of life, the
innovation of life, and the tremendous connectivity amongst
all life on the planet. You come away from reading the
genome recognizing that we are so similar to everything else
on the planet.
My take-home message from reading this genome is that we are
such a piece of every other living thing on this planet and
every innovation in us, we didn't really invent it. These
were all things inherited from our ancestors, some of which
were yeasts, some of which were slugs. And we're walking
around with all these inventions that we got from our
forebears, and making good use of it. But we shouldn't be
too proud about how wonderful the human is. Very little
that's human was invented in humans.
Krulwich: What is the intellectual excitement here
[in studying the genome]? By your description, once the
DNA sequencing
machines are invented, I just go whoop, whishh, pishh! And
then like I can take a nap, and then out comes the
answers.
Lander: You wish. It's just that, of course, since
one is on the cutting edge -- I guess in electronics they
always call it "the bleeding edge" -- they know what they're
talking about, because nothing really is working as you
expect. All of the stuff we're doing will be working
perfectly as soon as we're ready to junk it. So we get the
tremendous excitement about working with new ideas, that are
almost completely functional. And so you're constantly
figuring out why they're not completely functional. It's
sort of like flying a very large plane and repairing it
while you're flying. It's a challenge, right?
The exhilarating thing about the genome project is we set
ourselves the challenge of trying to get this done really
fast. If this wasn't important stuff, you'd sit back and
say, "Let's take a couple of years, and let's get it all
worked out just perfectly. We'll make sure it's humming.
We'll work out everything, and it will be flawless."
Of course, the information is too interesting. The
insatiable hunger for this information is pressing, and so
you say, "Let's get the plane into the air, and we'll work
out the rest, 10 percent of the bugs, while we're on our
ascent." And it's an interesting challenge.
It attracts intellectual people, because it takes a lot of
thinking to figure out what's wrong. It attracts people who
sort of love the exhilaration of working together with other
people. It attracts people who love the terror of not
knowing whether this is all going to fall together. And it
also attracts people who realize how much incredible
information about medicine and evolution is pouring out the
back end, and that if we can only get it to flow perfectly,
we have a lifetime's worth of information to pour over, if
we can just get it to work.
Krulwich: And you didn't mention money.
Lander: Well, in fact, it flows from our computers
straight onto the Internet every 24 hours without patents,
without any restrictions whatsoever. The one commitment we
made was that taking public money to do this, this was a
kind of basic knowledge that 10,000 medical scientists
around the world could use every day, 2,000 biotech
companies, 30 pharmaceutical companies, and that there's no
way that we could do as much with this information all alone
as the whole world could do together.
And so the folks who did the genome project decided very
early on that we would just put our data on the Web, the
information we got every single day, 24 hours a day, and
that way, anybody who is working on some brain degeneration
or some bowel disease could look at it, and see if they
found something really useful.
So when we're writing up the paper about the human genome
sequences, we're doing right now, we have a tremendous
pleasure. Most scientific papers you speculate on how this
stuff is going to be useful. We can write a whole section
about dozens and dozens and dozens of papers on different
human diseases that all have worked because of the sequences
put out there.
I mean the folks at the genome centers around the world are
the tremendous heroes of this project, because everybody did
this with no personal gain. Everybody did this because they
knew that they were doing the single most important project
they could be involved in in their life. And that they would
be proud to tell their grandchildren what they spent these
years doing. And the way we did it was incompatible with
people seeking personal gain out of particular genes. It
wouldn't have worked unless everybody rode together.
Krulwich: This doesn't mean, yourself included, that
people couldn't go across the street and work for a private
company?
Lander: You can go work for a private company. It
means you can use this information later, once it's been
freely available to everybody to make important discoveries.
I have no objection to patents. I have no objection to
companies. Our feeling is that the basic information that
the letters in the cells were such fundamental
infrastructure, such a foundation that that had to be made
available without any restrictions, and then companies can
go off and use our information, file patents, make millions
of dollars. Scientists can do that. Anybody at the genome
center can go off and do research on it. But for starters,
the basic information has to be available to everybody. And
then the value can be added to it. I think that's the right
solution for the public.
Krulwich: Well, first of all, did it ever strike you
as odd that there you could patent something that we all
have in almost all of our cells? Something that's so natural
as DNA, that it could become somebody's private property and
not mine?
Lander: Well, the patent office says, of course, that
you can't patent the gene in the human body. All you can do
is get a patent on taking it out of the body and putting it
into a bacteria to produce a protein or using the DNA for a
diagnostic test. So they profess that you're not really
patenting the human gene.
Krulwich: You're taking the stuff out of us and
putting it like a museum-like pristine place, and then when
it's isolated and pure --
Lander: You might use it to make a protein.
Krulwich: Yes. But it's still me.
Lander: Well, of course it's still you. But the
patent office thinks once it's outside of you, it's an
invention; it's not you.
Krulwich: That's an odd idea.
Lander: Well, it's an odd idea, but when you get down
to it, it's not completely nutty to think about allowing
some patents, because some of the proteins in the body can
be used as drugs as pharmaceuticals. If we didn't allow some
patenting, then a pharmaceutical company, thinking about
spending $100 million in order to develop this protein as a
drug would say, "It's a stupid idea. Somebody else could
come along after we have a successful clinical trial, not
have invested the money, and just make the protein." So
society says, "All right. We'll grant the monopolies to
these inventors."
Krulwich: Which lasts how long?
Lander: Twenty years. It used to be 17 years; it's
now 20 years. "And because of that, we're going to try to
incent people to make inventions." It's not a bad idea in
principle. What bothers me about the patenting system is
over the last 10 years, we've been giving away patents for
very trivial amounts of work.
I don't object to giving somebody that limited-time monopoly
when they've really invented a cure for a disease, some
really important therapy. I do object, because I think it's
a crummy bargain, for society to giving a monopoly when
somebody has simply described a couple hundred letters of a
gene, has no idea what it does. Has no idea what use you
could have in medicine. Because what's going to happen is
you've given away that precious monopoly to somebody who's
done a little bit of work, and then the people who want to
come along, and do a lot of work, to turn it into a therapy
well they've got to go pay the person who already owns it. I
think it's a bad deal for society.
Krulwich: I want to make sure I understand this. So
if this were back in the 1880's, and it was the mining
[industry] -- I see a mountain. I think maybe there's gold
up there. I could go file a claim. I don't even have to go
up the hill. I don't have to dig a hole, just do it.
Lander: We went through this with the Homestead Act
in the middle part of the 1800's. The government said,
"We'll give you a big tract of land, if you will work the
land for three years." That was a great bargain, because we
gave land and people developed its economic uses. If the
Homestead Act instead said, "We'll give you land that all
you have to do is walk the boundary," we would have
accomplished nothing. That's the difference.
If you've got to work your claim, if you've really got to by
the sweat of your brow add value for society, I don't object
to these limited-time monopolies. But if we're giving away
the store for effectively no work, I think society is
getting the short end of the bargain.
Krulwich: Let me see what you get. If you haven't
done a whole lot, I guess you want the people to do some
serious science, some research, some benchmark, actually
manipulate these things?
Lander: I want, in order to get a patent, that
someone do something that we would all really call useful.
Not just that a patent examiner might say is technically
satisfying the condition of utility, but that a person on
the street would acknowledge, "That is useful."
Krulwich: Were companies patenting segment after
segment after segment, doing almost nothing at all to get
the patent?
Lander: Oh, yeah. One could write automated programs
to file patents on the automated sequences you generated.
Krulwich: No!
Lander: Oh, yes. Sure. Why not?
Krulwich: You'd have a robot do the science--
Lander: You'd have a robot write the patent.
Krulwich: A robot do the research?
Lander: Yeah.
Krulwich: And what would you do; you'd just become a
landlord?
Lander: You got to put the stamp on it.
Krulwich: So that's stopped, right? I mean the patent
office changed its mind.
Lander: Well, the patent office has been slowly
ratcheting up the standards. I honestly don't know if there
really is an appropriate level right now. They're certainly
imposing more and more of an obligation on a would-be
inventor to say that they've done something really
meaningful....
Krulwich: Let's say now I have to worry, though, that
if I work this particular set that some landlord is going to
call me up and say, "I own this. You have to pay me to work
here." Isn't that what the landlord does?
Lander: Well, you mostly have to worry if you're a
scientist in a company, who is trying to make some important
therapeutic, some cure, based on that segment. If you're a
research scientist, just doing research, in principle the
other company could call you up and tell you to cease and
desist. In practice, of course, they're not going to bother.
In fact, they're happy you're doing it, because you're
adding value to their property.
Krulwich: Oh, I got it. Okay.
Lander: You know, you're putting a hotel on their
square.
Krulwich: So let's change the argument. I'm a company
trying to do work on this, this, and this rung of the
ladder, because I think that I can maybe develop a cure for
cancer right here, just for the sake of argument. But, of
course, I have to worry that somebody owns this thing.
Lander: Oh, you have to worry a lot that this region
here that you're working on that might cure cancer has
already been patented by somebody else and that patent
filing is not public. And so you're living with the shadow
that all of your work may go for naught.
Krulwich: Because one day the phone rings, and says,
"Sorry, you can't work here. Get off my territory."
Lander: That's right.
Krulwich: Or "You can work here, but I'm going to
charge $100,000 a week," or "You can work here, and I'll
charge you a nickel, but I want 50 percent of whatever you
discover."
Lander: And the problem here is even worse, because
many companies don't start the work whenever there's a cloud
over who owns that. If there's uncertainty, companies would
rather be working some place where they don't have
uncertainty, and, therefore, I think work doesn't get done,
because of the confusion over who owns stuff.
Krulwich: Is there any place on the genome that is
safe to work on, that's unclouded by legal uncertainty?
Lander: No. We're just not aware necessarily of what
anybody has done, and so there's no place concrete that's
unclouded.
Krulwich: So one argument could be that this patent
system that we have frustrates our very basic desire which
is to get medicines to people quickly.
Lander: I agree.
Krulwich: Very briefly, I need you to help me
describe what the business of these businesses is? In the
case of Celera and some of these other companies, they don't
actually seem to be in the landlord business. At least to
hear them describe it, they're in some other kind of
business. What is that business?
Lander: It's interesting. The companies that are
involved in sequencing the genome, and there are really
three that have popped up all through the course of the
1990's, could either be seen to be in the landlord business,
holding patents on genes, and waving them around when people
want to come settle on that gene, or they could be seen as
being in the database business. That is having some computer
database, where any researcher who wants to gain access to
information about the genome could pay a subscription fee
and get the data, plus some tools to study it.
Krulwich: Would it tell you the names of the
universities that are working that part of the territory,
and the names of the professors and their telephone numbers
and the articles they have published? And what--
Lander: It depends whether they put that into the
database. In the first instance, they could just tell you
the letters. Maybe they might also tell you, "We think there
are genes here." Maybe they might also tell you, "We think
this gene is expressed in your intestines." And maybe they
would tell you, "Here're all the papers that have ever been
written about this gene." That's valuable information. There
are databases of geography of the United States that will
tell you, you know, where the cities are, where the
buildings are, who lives in what buildings. These are useful
databases, and I have no objection to having databases
available.
But the raw data, for example, of who is in the phone book,
that should be available to everybody. But if you want to
build a commercial database, that adds more value and
aggregates together those people who live in the same
neighborhood and also, you know, buy books from Amazon.com
and all these other -- more power to you, that's great.
Krulwich: Finally, what was the most fun that you
have had since this whole thing began? Was it standing there
at the White House with all these prime ministers?
Lander: No.
Krulwich: Was it the toast you gave, which we have,
which is beautiful, where you're looking at the people who
helped you get to the billionth base pair, when you had the
sort of daddy look on? Or what was it? Was there some
intellectual thing?
Lander: I went into biology because I have the sense
that it was one place where you could really share your
pleasures, where you could really share what you were doing
as part of a whole community. That's what I got out of the
genome project.
We pulled together through some really challenging, really
difficult times, and we did it. We did what we set out to
do, and it's something we're all going to tell our
grandchildren about. And it's pretty wonderful. That feeling
of having pulled together with other people and accomplished
something that matters, let alone something that I think
will matter for hundreds of years, that's a pretty wonderful
feeling. I couldn't have asked for anything better in all
the time I was wandering around figuring out what to do with
my career. It's a tremendous gift.
Krulwich: Was this your Mark Spitz U.S. Hockey Team
moment, after which there will never be as high a high?
Lander: Oh, golly, no. I think this was a very
special time in its own way. It was also a very stressful
time, it was a challenging time. But I think it was special.
But, you know, the fun is just going to start now. I think
it's a different kind of fun. I think we have finally gotten
to the other side of this massive genome. We saw this vast
hill, this vast mountain standing in front of us 15 years
ago. Now here we are. We've gotten over to the other side.
And there's this huge new land to explore.
So it was a tremendous feeling to have been part of an
expedition going up this mountain and coming down the other
side. And that probably won't be replaced by any other
experience. But, boy, the experience of seeing this huge
valley now just spread out in front of us! That's going to
have years and years of fun ahead. I'm really looking
forward to that part, too.
Interviews:
Collins
|
Lander
|
Venter
Photo: WGBH/NOVA.
Watch the Program Here
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Our Genetic Future (A Survey)
Manipulating Genes: How Much is Too Much?
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