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The Gene Hunters

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FRONTIERS Profile: Eric Lander

3 pages: | 1 | 2 | 3 |

Photo of Alan and Eric LanderIn "The Gene Reader", Alan gets an insider's look at the Human Genome Project from Eric Lander, the director of the Whitehead Institute for Genome Research. Lander was instrumental in bringing the first draft of the human genome to the public in February 2001. Here, he shares with Alan his enthusiasm for genetics and the enormous potential it holds.
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Pasting Pages

LANDER: The sensible way to read a book is, you sit down at the beginning and you read sentence by sentence from chapter one to the end. I wish we could do that with the human genome. We can't come close. So instead, the nutty way that you read a genome is, you take the book, you tear it up into lots of pieces, you read the sentences, and then you paste them back together.

"If you like jigsaw puzzles, you'll like the human genome. This is the world's top jigsaw puzzle."

AA: But how do you know you've got it in some kind of logical sequence?

LANDER: Well, that's the challenge. You use a lot of information about the letters themselves, so you use a computer to put together sentences that could fit only with each other. But, Half of the human genome is repeat sequences. This is the bane of our existence in putting it together. So we use only the unique bits. If you like jigsaw puzzles, you'll like the human genome. This is the world's top jigsaw puzzle with about 70 million pieces. And our goal is to get every one of the 3-5 billion letters right.


In the Beginning

AA: Let me go back to the very beginning. What do you start with?

LANDER: The first thing you do is, you start with informed consent from the patient. That's very important.

AA: And then what do you do?

"We're reading about 60 million letters per day, just in this facility here. It's a stunning rate."

LANDER: Then you might take a blood sample. In your blood, there'll be lots of white blood cells that have DNA in them. There's DNA in every other cell in your body, but you're probably a little more willing to give blood up than a chunk of muscle or a hunk of brain or something like that. So, you take maybe 20 mils of blood out of somebody and you then spin the white blood cells down in a centrifuge, crack them open, and purify the DNA out of the blood cells. That gives you total human DNA. All 3 billion letters of the human genome are there. But we want to read each letter multiple times to be sure we get it right. Maybe 10 times? So we actually collect about 30 billion letters. We're reading about 60 million per day, just in this facility here. It's just a stunning rate. You could read the entire genetic code of some fungus like brewer's yeast in the course of a day here. You can read the bacteria in your gut in the course of a couple of hours here.

AA: Even the so-called "junk DNA." Everything gets read?

LANDER: Well, we had no good technical way to pick out the part of the DNA that contained the important information. More importantly, who's to say we knew what was the important information? It turns out to be far better to read it all. After all, evolution has spent 3.5 billion years getting this code together- who am I to say it's not worth reading the end of chromosome 16? So we're going to collect the whole thing, we read the whole thing, and make sense of it. It's going to take, I think, decades to make full sense out of the novel, but that's the case with any classic. You still read Shakespeare, and you get new meanings out of it. We're going to get a first pass read of the thing now, but I'm sure there are glosses on the text that are going to emerge over the course of the next centuries, and somebody's going to come back and recognize something in a sentence, and say, "we never realized it was telling us that!". It is text, it's great. And it is historical text.
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