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NOVA scienceNOW: July 2, 2008

PBS Airdate: July 2, 2008
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NEIL deGRASSE TYSON (Astrophysicist/American Museum of Natural History): On this episode of NOVA scienceNOW: can a new DNA test tell us what diseases we'll get in our lifetime? They say it's easy as...spit.

ELISSA LEVIN (Navigenics, Inc.): Spit.

NEIL deGRASSE TYSON: That's right. Just fill up a container with saliva—took me 90 seconds—send it off to a lab, and read your genetic future.

DIETRICH STEPHAN (Navigenics, Inc.): This is your actual genome. And we want to do that across the entire population.

NEIL deGRASSE TYSON: And one of these two paintings is a van Gogh original, worth millions, the other, a copy, created by this artist for a NOVA scienceNOW computer challenge.

CHAD COHEN (Correspondent): Do you think she has a shot against the computers?

ELLA HENDRIKS (Head of Conservation, Van Gogh Museum): I think it will be a challenge, yeah.

NEIL deGRASSE TYSON: Three teams of computer scientists come up with programs to pick out our fake among five van Gogh originals.

ERIC POSTMA (Maastricht University): These are genuine van Goghs.

NEIL deGRASSE TYSON: Will this new technology work? The results may surprise you as much as they did us.

Also, the scientists who built this machine say it can make like a tree...

KLAUS LACKNER (Columbia University): We are trying to mimic what a tree can do, and these are the leaves of that tree.

NEIL deGRASSE TYSON: ...and pull carbon dioxide right out of the air to reduce global warming. And where did the idea come from? His 12-year-old daughter's science project.

We'll show you how and more, on this episode of NOVA scienceNOW.

Funding for NOVA scienceNOW is provided by...

Americans are living longer, spending more on healthcare. At Pfizer, we're working on ways to help, with medicines that help prevent illnesses, with programs that provide our medicines to people without coverage, and new partnerships to keep costs down and keep people healthy.

And by the National Science Foundation, where discoveries begin. And...

Discover new knowledge: biomedical research and science education. Howard Hughes Medical Institute: HHMI.

And the Alfred P. Sloan Foundation, to portray the lives of men and women engaged in scientific and technological pursuit.

And the George D. Smith Fund.

And by PBS viewers like you. Thank you.

PERSONAL DNA TESTING

NEIL deGRASSE TYSON: Hi, I'm Neil deGrasse Tyson, your host of NOVA scienceNOW.

It seems like every week, scientists uncover more secrets of our DNA, revealing how our genetic code can shape and influence our lives. And for some, this is scary, raising fears that insurance companies or employers might see our genetic profile and hold it against us.

BUREAUCRAT NEIL: Well, Mr. deGrasse Tyson, I've seen your genetic profile, and it's not pretty. In fact, you're much too much of a genetic risk for us.

NEIL deGRASSE TYSON: But some say that knowing our genetic risk for disease will actually lead us to longer, healthier lives.

DOCTOR NEIL: Well, Neil, I've reviewed your genome. Here are my recommendations. And we've prepared a bottle of vitamins especially for you.

NEIL deGRASSE TYSON: Well, thank you!

DOCTOR NEIL: Live long and prosper.

NEIL deGRASSE TYSON: So what can genetic testing actually tell us about our chances for a long and healthy life? And will that knowledge help us or hurt us?

Can you imagine a simple test that tells you how healthy, or not, you'll be in the future: if you'll get cancer, gradually lose your memory, or be suddenly stricken by a heart attack? Sounds like something out of science fiction, but could this be possible today?

Judging from the headlines, you might think so. New companies have just burst onto the scene, proclaiming the dawn of a new age of personalized genetic testing.

DIETRICH STEPHAN: We're at the beginning of a medical revolution. So this is where the DNA arrives.

NEIL deGRASSE TYSON: Dietrich Stephan is a founder of Navigenics, which specializes in medical testing. For a fee of $2,500, they'll screen your DNA and tell you your genetic risk of getting a variety of scary diseases.

DIETRICH STEPHAN: We're testing an individual to provide them a snapshot of how genetically loaded they are so that they can potentially reduce their risk. And we want to do that across the entire population.

NEIL deGRASSE TYSON: The entire population getting their DNA scanned? It sounds a little like the movie GATTACA, where, from birth, everyone's destiny is foretold by their genes.

NURSE (GATTACA Film Clip): Neurological condition, 60 percent probability; manic depression, 42 percent probability; attention deficit disorder, 89 percent probability; heart disorder, 99 percent probability. Life expectancy: 30.2 years.

MOTHER (GATTACA Film Clip): Thirty years?

NEIL deGRASSE TYSON: I wondered what was lurking in my DNA, and Navigenics agreed to test me for free. There was just one thing I needed to do: spit.

Quick start guide.

ELISSA LEVIN: You have agreed to provide us with a saliva sample and...

NEIL deGRASSE TYSON: Spit.

ELISSA LEVIN: Spit.

NEIL deGRASSE TYSON: Looks dangerous.

ELISSA LEVIN: It's a couple of millimeters.

NEIL deGRASSE TYSON: Biohazard!

ELISSA LEVIN: Saliva is the most painless way to collect a sufficient sample.

NEIL deGRASSE TYSON: So you're telling me you want me to spit into a cup.

ELISSA LEVIN: Takes about five minutes.

NEIL deGRASSE TYSON: Five minutes of spitting.

ELISSA LEVIN: Correct.

NEIL deGRASSE TYSON: I'm thinking of pastrami on rye with provolone, bag of potato chips...

Luckily, it turned out I'm pretty good at salivating.

Thinking of a caramel candy bar...

Took me 90 seconds. My spit then traveled to a lab in California, where they extracted and analyzed my DNA.

DNA is made of long chains of four chemicals, best known by their initials: A, C, G and T. There's about six billion of these letters in the human genome, but reading every one is painstaking and expensive. So the latest tests look for things called "SNPs," short for single nucleotide polymorphisms.

DIETRICH STEPHAN: So, a SNP is really any position in the genome where there is variation between individuals in the population.

Nearly all of our DNA is exactly the same from person to person, but there are about three million spots where a single letter difference will commonly show up. Each of those spots is a SNP. It's just one letter, and, in most cases, we don't know exactly what it does.

You might have a C at one position, and I might have a T. We're both alive. We both have arms and legs and noses and brains and totally functional.

But those subtle variations are what make you and I unique and different. But it's also what predisposes individuals, subtly, to these common diseases.

NEIL deGRASSE TYSON: So which SNPs do I have, and what can they tell me about my health?

To find out, the DNA I provided in all that spit is squirted onto a silicon gene chip which holds millions of tiny fragments of reference DNA to compare with mine. Wherever a strand of my DNA fits with the sample DNA, the two will link and light up, revealing exactly what letters I have in certain spots.

So we're looking at my actual...

DIETRICH STEPHAN: This is your actual genome. And what you can see...

NEIL deGRASSE TYSON: As represented on this chip?

DIETRICH STEPHAN: Correct.

NEIL deGRASSE TYSON: The bright white spots reveal my SNPs.

Now what Navigenics will do is compare them to the SNPs of people with certain diseases. If I have particular SNPs in common with them, then I'm more likely to get those diseases.

Stephan believes that if my SNPs put me in the group more likely to get a disease—like diabetes, for example—I'll be more motivated to adjust my lifestyle and lower my risk.

It's a nice idea, but will it work?

DAVID ALTSHULER (Massachusetts General Hospital): I don't think we should tell anyone that this will help their health, because we really have no idea.

NEIL deGRASSE TYSON: Geneticist David Altshuler has serious doubts about the current value of this kind of DNA test.

DAVID ALTSHULER: It might help their health, it might do nothing to their health, and it might hurt their health.

NEIL deGRASSE TYSON: But how could a DNA test hurt your health? Well, take the case of Alzheimer's disease. There's a gene that works inside the brain, and one version of this gene can lead to Alzheimer's disease in old age. If you look at this SNP in your DNA and you have a G right here, there's a strong chance you'll have that dangerous version of the gene. If you have two copies of the G, one on each chromosome, your risk of getting Alzheimer's, though not 100 percent could be 10 times higher than average.

So what would you do with news like that?

RUDOLPH E. TANZI (Massachusetts General Hospital): There's a minority of people who...it won't bother them at all what their genetics are. They just live their lives, say, "I don't care." But I worry about the other side of the bell curve, those who get genetic information. They look fine when they get it, and then they go home and freak out, or, in some cases even, you know, may commit suicide.

NEIL deGRASSE TYSON: Even James Watson, who deciphered the structure of DNA and recently had his entire genome sequenced, did not want to know if he had the high risk version of the gene called "ApoE4."

Alzheimer's expert, Rudy Tanzi can't blame him. Tanzi strongly discourages most people from testing for ApoE4.

RUDY TANZI: It needs to be emphasized that whether you inherit one or two copies of ApoE4, you are not guaranteed to get Alzheimer's disease in your lifetime. So it just doesn't make a whole lot of sense to do an E4 test for Alzheimer's disease, given that it's not a reliable predictor for the disease.

NEIL deGRASSE TYSON: This Alzheimer's test is so controversial, some genomics companies won't even offer it, but Navigenics does.

I thought long and hard about whether I wanted to hear my status, even if I couldn't do anything about it, and decided to find out. I'm a little worried, but I, kind of, think that I'd rather know than not know. Because I can use that information to adjust how I might live going forward.

Finally, the moment of truth arrives.

Have you seen them yet?

ELISSA LEVIN: Well, we review everything.

NEIL deGRASSE TYSON: That's a yes.

For about 10 diseases, Elissa Levin, Navigenics' Director of Genetic Counseling, gave me two numbers: first, an American man's average lifetime risk of getting a disease, and then my genetic risk, based on how many good or bad SNPs I had.

So, I'm looking here. Obesity, 22 percent?

They say my risk of becoming obese is 22 percent, while the average risk for males in the population is 25 percent.

ELISSA LEVIN: So you're just under the population average.

NEIL deGRASSE TYSON: I'm a little less likely...

ELISSA LEVIN: You're a little less likely, based on your genes.

NEIL deGRASSE TYSON: So, heart attack?

ELISSA LEVIN: That's about 52 percent.

NEIL deGRASSE TYSON: Fifty-two? And I'm coming in...?

ELISSA LEVIN: At about half of that.

NEIL deGRASSE TYSON: About half of that.

But what about Alzheimer's, do I have a G in those dangerous spots? Nope, the test said I had an A on both chromosomes.

This tells you I probably don't have that gene.

ELISSA LEVIN: I have to say this is a pretty stellar profile.

NEIL deGRASSE TYSON: But what's this? It looks a little high.

And so, prostate cancer: 17 percent in the general population, and I come in at 20 percent.

ELISSA LEVIN: Right.

NEIL deGRASSE TYSON: So, remember, these SNPs cannot tell you for sure if you'll get these big common diseases.

DAVID ALTSHULER: First of all, they're only clues. We don't know what they mean. We don't know all the mutations in those genes. We certainly don't know how they work biologically. We have no clue what they mean clinically. We have no idea how they would affect the treatment you should take.

NEIL deGRASSE TYSON: Even if we could pinpoint all the genes that contribute to the big common diseases, that still wouldn't be enough.

We know, from studying identical twins, genes can't be the whole story. Even with the exact same DNA, one twin might get cancer, the other won't. And we still don't know why.

RUDY TANZI: For the majority of age-related diseases that, you know, challenge healthy aging, we're still in process of figuring out the genetic factors, never mind figuring out how they interact with the environment or even what the environmental factors are. These are early days.

NEIL deGRASSE TYSON: For now, skeptics say these tests may be no more predictive than a good family history.

But what if we could find a cheap way to read, not just SNPs, but the entire genomes of many people, as they're trying to do here at Harvard Medical School? If we combine those with personal histories, intimate details of our habits and behaviors, could we get closer to overcoming the big killer diseases?

DAVID ALTSHULER: The more sequence we capture in people with disease, 'til it's complete, and different numbers of people in different populations, we will, I am entirely confident, learn about disease and human biology, and we'll learn about human history. We're going to learn about ourselves, so...knowledge itself can be challenging.

ART AUTHENTICATION

NEIL deGRASSE TYSON: How do you identify a true masterpiece? We don't usually think of a great painting as something that can be reduced to numbers.

Got a couple more threes right over here.

But a few scientists might disagree. They say that if you take away the color and break down a painting, brushstroke by brushstroke, you'll find a complex pattern of numbers, a pattern unique to every artist. And as correspondent Chad Cohen reports, it could provide a crucial clue if you're trying to tell the real thing from a clever forgery.

CHAD COHEN: Deep in the storage vault of the Van Gogh Museum, in Amsterdam, a precious canvas is being photographed. The Reaper, painted by Vincent van Gogh in 1889, has the thickly layered paint and bold curves the artist is so famous for. But are we looking at the real thing? Because there are two Reapers in this vault, one, as you might expect, worth millions; the other, a copy, worth no more than the oil and canvas it was painted with. Can you tell the difference? It's something hundreds of collectors ask the Van Gogh Museum to do every year, convinced they own a masterpiece by the great artist.

SJRAAR VAN HEUGTEN (Head of Collections, Van Gogh Museum): We get many questions for expertise here. Our opinion is asked all the time. And there are many fakes that have been around for decades.

CHAD COHEN: This is one of 30 fake van Gogh's created by a German art dealer named Otto Wacker, in the 1920s. He came up with the ingenious method of priming his canvases with white lead paint, to build up the thick layers van Gogh is famous for, then added bright colors on top. For a few years, the Wacker forgeries managed to fool the greatest van Gogh experts in the world.

SJRAAR VAN HEUGTEN: It is a problem. It is a problem for any renowned artist, because money, of course, is very tempting.

CHAD COHEN: This is serious money: 50, 70, 80 million dollars a piece for some of the best known paintings. Even the Van Gogh Museum was fooled into buying a fake back in the 1970s. It's a 19th Century painting called View of the Ij, Amsterdam's inner harbor. It wasn't originally intended as a fake, but years later someone forged van Gogh's signature onto the canvas. So how do you determine if a painting is the real thing? In May of 2007, the Van Gogh Museum explored one of the latest scientific methods of art analysis, by hosting the first international workshop on computer image processing.

ERIC POSTMA: These images are represented in terms of numbers.

CHAD COHEN: Eric Postma directed the technical presentation.

ERIC POSTMA: The purpose of the project was to look at these paintings and try to determine if we could distinguish between real and fake van Goghs.

CHAD COHEN: The computer scientists focused on one of the most revealing traits of van Gogh's work. As the museum's head conservator, Ella Hendriks showed us, it's the way he applied paint to his canvas.

ELLA HENDRIKS: I would tend to really want to get close and look at these, for example, these very nice white strokes, in the foreground, that were added at a late stage. If you look very close, you can see these, sort of, trailing drips of paints, as he literally scooped up the paint from the canvas, lifting his brush and then carrying the trail of paint.

CHAD COHEN: It turns out that van Gogh's brushstrokes are crucial markers, not only for critics and connoisseurs, but for computers as well.

ERIC POSTMA: The pattern of brushstrokes is very specific and very indicative of a painter. So the first selection that you make when you start to analyze these paintings digitally is to select the level of individual brushstrokes.

CHAD COHEN: The computer scientists create programs which examine a painting from different angles, to determine the direction of each brushstroke. Collecting the brushstroke patterns from more than 100 paintings establishes a baseline for van Gogh's style. But could the computer be fooled? Could an artist, specially trained to copy the old masters, duplicate van Gogh's style?

To find out, we commissioned Charlotte Caspers to carefully imitate every detail of van Gogh's brushstrokes. She's an expert in art reconstruction, using historical materials to copy famous paintings so museums can decide how to preserve the originals.

CHARLOTTE CASPERS (Artist and Conservator): The best would have been to sit next to the painting, but well, that was just not possible.

CHAD COHEN: The Van Gogh Museum doesn't allow artists to paint in front of the originals, so she made her own photos of The Reaper.

CHARLOTTE CASPERS: I couldn't bring the painting home, so I had to take a picture. And when it's a digital one, you can blow it up on your computer. So that is what I did.

CHAD COHEN: Knowing that the scientists would be focused on the pattern of van Gogh's brushstrokes, Charlotte's job was to perfectly match his technique.

CHARLOTTE CASPERS: I had a picture next to my canvas I was painting on. And I could blow that up so I could have a close look at the paint surface of the original painting from a picture.

CHAD COHEN: How do you think that trying to be him ultimately influenced the painting itself?

CHARLOTTE CASPERS: It's less spontaneous.

I was just switching all the time, my eyes, from my canvas to the picture and trying to do what he did. With charcoal, I did his outlines and near the folds and the indication of the face. And then I added yellows. And then, after that, I did something with dark lines. And then I added the highlights and the outlines. And I did the birds at the end. It was the last thing. It was fun to do.

CHAD COHEN: We had a young artist copy one of the master's paintings. Did you, did you get to see the copy?

ELLA HENDRIKS: I did get to see it, yeah.

CHAD COHEN: What'd you think?

ELLA HENDRIKS: I think she did a remarkable job because it's very...she's made a very accurate copy of the rhythm of the brushstrokes but managed to do it in a spontaneous way.

CHAD COHEN: So do you think she has a shot against the computers?

ELLA HENDRIKS: I think it will be a challenge, yeah.

CHAD COHEN: The challenge begins by turning Charlotte's copy of The Reaper into a color photograph, which is then turned into a high-resolution black and white scan.

Identified only by catalogue number, it takes its place beside five real van Gogh paintings, creating NOVA scienceNOW's test for three computer teams: Penn State University, Princeton University and Maastricht University. Eric Postma leads the Maastricht team.

So, here's a famous van Gogh.

ERIC POSTMA: Yeah.

CHAD COHEN: Van Gogh.

ERIC POSTMA: Van Gogh.

CHAD COHEN: Van Gogh.

ERIC POSTMA: Van Gogh.

CHAD COHEN: Van Gogh: The Sower.

ERIC POSTMA: The Zier.

CHAD COHEN: However you want to say it.

How do you begin? So you look at this, it's a beautiful painting. But you're going to strip it of its beauty, one layer of its beauty right now?

ERIC POSTMA: Yeah. In fact, what it'll be, because we translate the entire painting into numbers...

CHAD COHEN: Postma's software scans the whole painting, identifying areas of contrast. The more contrast, like the dark tree branch against the light sky, the larger the number assigned by the computer. If the contrast is less extreme, like the edge of the sun against the sky, the number is smaller. When all the contrast patterns are combined, a statistical portrait of van Gogh's style is created.

ERIC POSTMA: Well, these are genuine van Goghs. And this is a known fake, so-called "Wacker" fake. The faker tried too hard to mimic van Gogh.

CHAD COHEN: And by trying too hard, that means?

ERIC POSTMA: Too much.

CHAD COHEN: Painting too much?

ERIC POSTMA: Too much, exactly.

CHAD COHEN: Someone copying van Gogh paints too many brushstrokes to get it right, and the computer identifies them as areas of higher contrast. First the program analyzes the brushstrokes from six different angles then combines them to reveal areas where they overlap. More overlapping brushstrokes show up as brighter areas; fewer overlaps are dark.

Look at this famous painting van Gogh did of his bedroom. As the computer separates out each angle, it highlights the brushstrokes painted in that direction. Putting them all together reveals a brushstroke map of the painting. Now look at the Wacker forgery. The computer identifies more overlapping brushstrokes in every direction, 10 times as many as the van Gogh bedroom. The genuine van Gogh paintings display fewer brushstrokes than the forgery.

ERIC POSTMA: If you deliberately try to mimic van Gogh, then it's not natural anymore, and then you tend to overdo it. And this overdoing it results in high numbers. And that could be one way of detecting a fake.

INGRID DAUBECHIES (Princeton University): I'd like to see what zoom-in gives there.

CHAD COHEN: Ingrid Daubechies and the Princeton team have also been looking at the six paintings in our test, searching for the fake.

INGRID DAUBECHIES: If you try to make a copy, you would pay so much attention to what you're doing that you probably paint it more slowly and with more restrained hand than van Gogh himself would have painted, and we expect that to transfer, as well.

CHAD COHEN: For James Wang and Jia Li from Penn State University, Charlotte's copy seemed to blend in with the other five paintings.

JIA LI (Pennsylvania State University): Just by looking at the pictures, they all look very van Gogh, so that's why, later, we also tried a statistical modeling approach.

CHAD COHEN: All of the science teams had less than a week to distinguish the fake from the real van Goghs.

Would they pick The Sunflowers? The Sower? Any of the other three genuine van Gogh's? Or would any of their computer programs successfully choose Charlotte's version of The Reaper? The analysis is finished, and it's time to take her painting to the Van Gogh Museum, where the scientists are waiting.

Okay, the moment of truth. Do you all have an answer? We're ready to bring in the artist? Okay, Charlotte. This is Charlotte Caspers. She painted the painting that you guys tested.

INGRID DAUBECHIES: Very nice to meet you.

CHAD COHEN: Do want to come on over and reveal it? Well, bring it on over. Don't open it yet. Bring it. Bring it on over, Charlotte. All right, so what do you all got?

JAMES WANG (Pennsylvania State University): Six-eighty-seven.

CHAD COHEN: Six-eighty-seven.

INGRID DAUBECHIES: Six-eighty-seven, the one...

CHAD COHEN: You guys match. That's two for 687.

ERIC POSTMA: And that's three for 687.

CHAD COHEN: All right. That's your final answer? You're sticking with it?

INGRID DABUECHIES: Yes.

CHAD COHEN: All right. Charlotte, let's see.

INGRID DAUBECHIES: Yes, yes, yes. Yes. Yes!

CHAD COHEN: Six-eighty-seven, The Reaper.

SHANNON HUGHES: Oh, yes. Got it. Got it!

JAMES WANG: So how long did it take you to finish the painting?

CHARLOTTE CASPERS: I worked two days on this one.

ERIC POSTMA: How long did it take you to analyze the painting?

JAMES WANG: Oh, we took two days, too.

CHAD COHEN: In fact, van Gogh himself completed many of his most famous paintings in two days or less, and they've kept art collectors and experts busy for more than a century. They're not there yet, but computers will ultimately speed the process along.

ERIC POSTMA: The most valuable thing about these techniques is that it can help art experts. You just can scan over the entire painting. And they do it in a completely unbiased way, and that's the great advantage of computers.

CAPTURING CARBON

NEIL deGRASSE TYSON: Every creature on Earth does the same thing. We take in oxygen and then give out carbon dioxide, with the same breath. And while we're putting out CO2, trees, like this one, and other plants are sucking it right up. They need it to survive!

But with worldwide population growth and increased fossil fuel consumption, we're now putting out more CO2 than our trees and plants can absorb. And since CO2 is a greenhouse gas, there're fears that all this carbon dioxide is heating up our planet.

For some the solution is obvious. Correspondent Peter Standring met up with some inventors trying to design a very "green" machine, one that can "make like a tree..."

PETER STANDRING (Correspondent): In a warehouse on the outskirts of Tucson, Arizona, Professor Klaus Lackner has come up with an idea even he admits is a bit fantastic. He's attempting to compete with Mother Nature.

KLAUS LACKNER: We are trying to mimic what a tree can do. And these are the leaves of that tree.

PETER STANDRING: Mimic a tree?

KLAUS LACKNER: Some people would say this can't possibly be done, but then, on the other hand, every tree can do it.

PETER STANDRING: Every tree, in fact every leaf, is like a tiny factory, taking in carbon dioxide from the air and using it to make the energy it needs to survive. In the process, it releases the oxygen that we need to live.

Klaus's version of a tree also pulls carbon dioxide out of the air. Not for its own survival, but to help us fight global warming. Sounds pretty incredible? Well, so is the way he came up with the idea.

It all started a decade ago, when his 12 year-old-daughter, Claire, came to him for advice.

KLAUS LACKNER: When I started to think about this problem, I was looking for ways of doing experiments. And, just about that time, Claire came to me in the study at home and said she is looking for an experiment to do for her science fair.

CLAIRE LACKNER (Student, Princeton University): I was in middle school, and I had to do a science experiment for my science class. And so I talked to my dad about various ideas and he suggested this.

KLAUS LACKNER: I said, "Why don't you pull CO2 out of the atmosphere?"

PETER STANDRING: Pull carbon dioxide out of the air? A tall order for a little girl. But, as the daughter of a renowned scientist, Claire already knew about global warming. She understood that when sunlight enters the atmosphere and strikes the Earth's surface, some of it is reflected back towards space in the form of heat.

Greenhouse gases like CO2, carbon dioxide, work like a chemical blanket to trap heat and keep the planet nice and warm. But the increased burning of fossil fuels was generating so much carbon dioxide that our planet's temperature appeared to be rising at an alarming rate.

But how could you just pull CO2 out of the air?

PARROT: Hello.

PETER STANDRING: Claire had an innovative idea.

CLAIRE LACKNER: I went to the local pet shop and bought a fish pump. I filled a test tube with sodium hydroxide. Next, I attached the fish pump to the test tube, turned it on and ran air through it all night.

PETER STANDRING: As Claire slept, her experiment was hard at work. The fish pump was forcing air containing a small percentage of CO2 into the test tube.

CO2 is an acid, much like vinegar. Sodium hydroxide, the liquid in the test tube, is a base, kind of like baking soda but stronger, a lot stronger. It's made of lye; the nasty stuff that cleans out your drain.

When acids and bases meet, they not only attract, but they bind to each other. It's called an acid-base reaction.

CLAIRE LACKNER: So the carbon dioxide binds to the sodium hydroxide and leaves the air.

PETER STANDRING: Claire succeeded in capturing carbon dioxide straight from the air, won a prize at the science fair, and changed the course of her father's life.

KLAUS LACKNER: I was surprised that she pulled this off as well as she did, which made me feel that it could be easier than I thought.

The first sketch I made ended up looking like a tuning fork or a goal post with Venetian blinds.

PETER STANDRING: A far cry from Mother Nature's design.

KLAUS LACKNER: The first reaction of most people, is, "Why take CO2 out of the air, where it's more dilute than in any other place? Clearly, it must be easier to get it out of a power plant." But not all of the CO2 comes out of a power plant.

PETER STANDRING: A lot comes from cars, trucks and airplanes burning fuel. Once in the air, CO2 is very dilute, making the idea of capturing it sound close to impossible.

If Klaus was going to make this far-out idea a reality, he was going to need some practical advice.

KLAUS LACKNER: If you look at Claire's experiment what she had is a test tube.

PETER STANDRING: So he went to the Wright brothers, not Orville and Wilbur, but project manager and engineer Allen and Burton, another set of brothers, who, like their namesakes, don't shy away from a challenge.

ALLEN WRIGHT (Global Research Technologies): The Wright brothers were able to look at a bird in flight, so they knew it was possible to fly. Klaus and I will look at a tree and say, "Well, you know, that tree is capturing carbon dioxide out of the air. We know it can be done; got to figure out how to do it."

PETER STANDRING: Not just in the laboratory with a tiny fish pump and a test tube, but on a global scale.

In 2004, they form a private company called GRT.

But the transition from a child's science fair project to the first synthetic tree is filled with obstacles. One, in particular, could stop them dead in their tracks. Their tree needs electricity to run. And whenever you produce electricity by burning oil, gas or coal, you also produce carbon dioxide. It's called an energy penalty.

If their synthetic tree produces more CO2 to run than it can capture, well, what's the point?

A delicate balancing act begins. For every choice the team makes there is a price to pay, an energy penalty. Can they somehow reduce the amount of energy they use?

KLAUS LACKNER: We needed to come up with a shape where you don't have to have an aquarium fish pump driving all the air through the system, but to have the wind just deliver the air and pass it through the collector.

PETER STANDRING: It all comes down to geometry. What is the size and shape of the perfect synthetic leaf, one that can remove the most CO2 from the air?

To find out, they construct a wind tunnel to study how air moves around and through a variety of surfaces.

KLAUS LACKNER: The easier it is to get air through, the more CO2 we can collect.

ALLEN WRIGHT: We tried an array of strings; we tried screens; we tried vertical plates of solid material that were smooth; we tried vertical plates that had a knobby surface.

PETER STANDRING: With each attempt, they measure the air pressure in the wind tunnel. A drop in pressure means the airflow has stopped, and that sample has failed.

ALLEN WRIGHT: Nineteen...so this is not the answer.

PETER STANDRING: It takes a year to find a shape that lets enough air pass through.

ALLEN WRIGHT: Perfect.

PETER STANDRING: It turns out to be long flat sheets.

ALLEN WRIGHT: The air would move through with very little resistance. It worked well.

PETER STANDRING: So air can move through their manmade leaves, but how will they capture CO2?

At first they follow Claire's lead, coating the leaves with sodium hydroxide. The chemistry is sound, but it's a nasty business.

ALLEN WRIGHT: It'll be a much tougher job for us.

KLAUS LACKNER: Sodium hydroxide is great to prove it can be done, but it has so many disadvantages.

ALLEN WRIGHT: Sodium hydroxide is a very corrosive material, it's not a good idea to get it on your skin; it's very harmful if you were to get it in your eyes. As a practical matter, trying to build a machine that works on sodium hydroxide would force us to use very expensive materials. It would drive the cost up significantly.

PETER STANDRING: The guys decide to abandon the idea of using sodium hydroxide when they make a startling discovery: this material. Now, exactly what this material is, the guys aren't telling.

BURTON WRIGHT: What is it?

ALLEN WRIGHT: Do I have your attention?

BURTON WRIGHT: We can't tell you.

PETER STANDRING: Turns out this is where science and commerce collide. Its true identity is proprietary, that is, until their patent comes through.

The team claims that this engineered fabric attracts CO2 just like sodium hydroxide, but with none of the pitfalls.

Here's how the system works: the nine-foot synthetic tree opens its doors letting air flow through its leaves, which, thanks to their mystery material, readily absorb carbon dioxide. The leaves are then sprayed to wash the CO2 away for storage.

The process does use electricity, but, in the future, they hope, green power will make the device even more energy-efficient.

Still one big question remains: what to do with all that CO2.

One option lies miles from civilization. Since 1996, a Norwegian oil company has gotten a lot of practice getting rid of CO2 by pumping it into an aquifer deep beneath the North Sea. The process is called carbon sequestration. But could the carbon leak out? If so, what effect would it have on marine life?

MARTIN HOFFERT (New York University): Once you've got enough gas under there, and it's leaking out, it could become a very serious problem.

PETER STANDRING: And how much CO2 can they put down there anyhow?

KLAUS LACKNER: I believe, in the long term, underground injection will not quite have the capacity we're looking for, so I am looking at another process which I refer to as mineral sequestration.

PETER STANDRING: There's a perfect example of it in New York City, on the campus of Columbia University, underneath a bronze statue of the school alma mater.

KLAUS LACKNER: She is sitting on this pedestal of serpentine rock. This serpentine has absorbed CO2, probably out of rainwater. It's known as geological weathering, and if you wait long enough, that's what will happen to all the CO2 we make.

PETER STANDRING: But it takes hundreds of thousands of years for Mother Nature to pull off geological weathering, and we don't have that long to wait, so Klaus is trying to figure out a way to speed it up in the lab.

As for his tree? He now has a working prototype, but many questions remain unanswered. Like, how well will it survive the elements? And who's going to a pay for it?

Is Klaus's tree too fantastic to be real?

MARTIN HOFFERT: You could have said that about the Wright brothers and Thomas Edison.

I can't sit here and tell you now that this is going to work. I can tell you now that it would be a terrible mistake not to do the research to find out.

KLAUS LACKNER: I believe that it is impossible to stop people from using the fossil fuels, so we need to develop technologies which allow us to use them without creating environmental havoc on the planet.

CLAIRE LACKNER: We are, as a world, changing the climate and changing the Earth. And we need to understand how we are changing it, and we need to understand what we would do: either how to fix it or to control how we change it.

PROFILE: PARDIS SABETI

NEIL deGRASSE TYSON: A lot of scientists, just like a lot of people, secretly wish they were rock stars. But really, how hard could it be?

Our love was like...a supernova...in the nebula of my soul,

But now...I find your heart...is just a big black hole.

Well, maybe it's harder than it looks. But in this episode's profile you'll meet a scientist who has a much better shot at becoming a real rock star. Don't believe me? Check this out.

Thirty-two-year-old Pardis Sabeti is a member of the rock band Thousand Days...singer, bass player and songwriter. She's a rocker by night; come morning, Pardis plays a different tune.

PARDIS SABETI (Harvard University): I'm a geneticist, with an interest in infectious disease.

NEIL deGRASSE TYSON: This is her stage by day, complete with its own dressing room and, of course, her instrument of choice.

In 2001, Pardis used her instrument to make a major breakthrough in genetics. She was combing through the human genome, trying to track natural selection.

ERIC LANDER (Broad Institute of MIT and Harvard): The process of natural selection is one of the most fundamental driving forces of evolution.

PARDIS SABETI: I'm looking for all the things that are beneficial in the human genome. Everything that I do is based on a very simple principle: things that are beneficial will spread through populations very quickly.

NEIL deGRASSE TYSON: Think of it this way, in natural selection, our DNA, our internal blueprint, constantly mutates, and some of those changes help us survive in our given environment. Those beneficial changes will be the ones that get passed down to future generations.

ERIC LANDER: If an advantageous mutation should occur, something that might protect you against a disease, for example, you'll leave more offspring, and your offspring will leave more offspring.

NEIL deGRASSE TYSON: And sometimes a genetic mutation will allow you to take advantage of a new source of food, for example, cow's milk. Thousands of years ago, most adults couldn't drink milk without getting sick. But after cows were introduced to Europe, people with a particular mutation that allowed them to drink milk safely could take advantage of this new food. They had a better chance at survival, and passed that milk-drinking gene on to the next generation.

Today, 80 percent of European adults can drink milk. That's a genetic brushfire.

Pardis figured out how to spot brushfires, like these, in a genome. She came up with an algorithm to compare genetic codes among hundreds of different people around the world, and identify the genes that have become very common, very fast, a sure sign of natural selection at work.

ERIC LANDER: The cool thing about what Pardis did was figure out what to look for in the first place, figure out how to sift the haystack to find the needles.

NEIL deGRASSE TYSON: And this idea has created a little brushfire of its own.

ERIC LANDER: Pardis' idea has been picked up by many, many groups now. It's now considered a routine tool for scanning the human genome to understand evolution.

NEIL deGRASSE TYSON: Pardis is a graduate of MIT and the Harvard Medical School. In one year, she received not only a seven-figure research grant from the Bill and Melinda Gates Foundation, but an honorable mention in Billboard's World Song Competition.

A female rocker who was born in Iran and is now a genetics professor at Harvard...wait, let me repeat that: a female rocker who was born in Iran is now a genetics professor at Harvard.

Pardis is her very own mix of a new generation's sensibilities with the old generation's credentials.

PARDIS SABETI: If you do you what you love, things happen fast. And I think that, that I don't manage my time well, I don't think I do anything special. It's just, I stick around things that I love.

NEIL deGRASSE TYSON: She learned that at an early age. Okay, maybe not this early, but her biggest lessons in life came from a unique family experience.

When Pardis was only two years old, her family was forced to leave their home in Iran because of the revolution. They found refuge in the United States, but they had lost everything.

PARDIS SABETI: You established a life in one country, and then you get to a new country, and it's sort of like: start over, learn a new language and get going. So it took awhile.

NEIL deGRASSE TYSON: All of this uncertainty meant that throughout her life there were only two things Pardis could count on, herself and her family.

PARISA SABETI (Pardis Sabeti's Sister): We were always, always together, which was great. And so then you felt safe.

NEIL deGRASSE TYSON: Parisa is Pardis's older sister, appointed playmate, and caregiver since birth.

PARISA SABETI: The moment that my sister came home, my mom made a big effort to say, "This is your sister. Take care of your sister." The two of us were always very, very close.

NEIL deGRASSE TYSON: After her family finally got its new life in America on track, Pardis was in the 9th grade, when her father was in a car accident that nearly killed him.

PARISA SABETI: He shattered both of his legs. It was an 18-hour operation to piece his legs back together.

PARDIS SABETI: Months and months and months in the hospital. They really didn't think he'd ever walk again.

NEIL deGRASSE TYSON: Her father made a full recovery, but this experience changed Pardis's life. She apprenticed with the doctor who performed the operation, which led to her decision to study medicine. And her father's example provided a lifelong lesson.

PARDIS SABETI: As long as I have a heartbeat, I'm fine. So I just do what I love, and I do it the best that I can. And if it all goes away, I'll just start over. You get this added drive because life is so precious.

NEIL deGRASSE TYSON: These days, Pardis has taken up the challenge of fighting malaria, a disease that infects at least 300 million and kills one to two million people each year. She's traveled to Africa to study how the malaria parasite interacts with its human hosts. And just like the human genome, the genome of this parasite, spread by mosquitoes, has now been mapped. Pardis is searching its genome for signs of natural selection in the hopes of understanding how this parasite develops resistance to the drugs we use to fight it.

PARDIS SABETI: The same types of methods I used to study what are the things beneficial in humans that allow it to continue to survive and stay on this Earth, we can do the same thing with malaria.

DYANN WIRTH (Harvard School of Public Health): This approach that Pardis is using is bound to lead to breakthroughs.

ERIC LANDER: What's wonderful is Pardis has no boundaries about what she'd like to do, what she's interested in doing. Her problem will be how to choose which of those she can fit into a 24-hour day.

NEIL deGRASSE TYSON: And while the future is anybody's guess, Pardis insists she's a scientist through and through. As she says, "It's much cooler than being a rock star."

PARDIS SABETI: You get these moments of thrill. There you are, at 3:00 in the morning, and you know something about how we evolved that nobody else in the world knows. It's a thrill of discovery. You make this breakthrough and you find something. It's this wonderful, wonderful scavenger hunt when you got to the end. It's just so great to be a scientist.

COSMIC PERSPECTIVE – BAD NEWS

NEIL deGRASSE TYSON: And now for some final thoughts on bad news.

Many people fear new information that might contain bad news beyond their control. But to fear bad news by hiding from it forfeits any opportunity to solve the problem.

Suppose the enterprise of science shunned bad news. We would never cure disease or mitigate disaster. We would crouch with our head in the sand, ceding our fate to forces we imagine to be beyond our control.

Take killer asteroids, for example. Without a space program, we could pretend they're not there or we might run away from where they might strike. But I'd much rather learn all I can about these objects, and then figure out a way to deflect them.

Even worse than bad news, for some people, is uncertainty, not knowing something for sure makes them uncomfortable. They just have to have the answer, the exact answer.

But to the scientist, uncertainty is a call to the wild. That's where data are in greatest need of improvement along the way to fully developed theories and experiments that have shed their shrouds of uncertainty.

For some cases, especially your health, you can actually influence the uncertainty yourself. If you wear a seatbelt, your chances of surviving a high-speed car accident are much higher than if you don't. And if you exercise and eat well, you can stave off diseases that you might be genetically prone to contract.

So bad news, uncertainty? I say, bring it on. To a person engaged in discovery, all information is good, even when it's bad.

And that is the cosmic perspective.

And now we'd like to hear your perspective on this episode of NOVA scienceNOW. Log on to our Web site and tell us what you think. You can watch any of these stories again, download audio and video podcasts, hear from experts and much more. Find us at PBS.org. That's our show. We'll see you next time.

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PRODUCTION CREDITS

Personal DNA Testing

Edited by
Dick Bartlett

Written, Produced and Directed by
Julia Cort


Art Authentication

Edited by
Ben Ehrlich & David Chmura

Produced and Directed by
Dean Irwin


Capturing Carbon

Edited by
David Chmura

Produced and Directed by
Terri Randall


Pardis Sabeti

Edited by
Jerry Pratt

Produced and Directed by
Robe Imbriano & Carla Denly


NOVA scienceNOW

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Executive Editor
Neil deGrasse Tyson

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For Lone Wolf Documentary Group

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Archival Material
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Special Thanks
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Ben Fry
Christopher Graves
Icelandic Tourist Board
Maryam M. Khani
Sam Krevor
Petqua
Peter Renee
StatoilHydro
Thousand Days
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Hans Ziock


Neil deGrasse Tyson is director of the Hayden Planetarium in the Rose Center for Earth and Space at the American Museum of Natural History.


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This material is based upon work supported by the National Science Foundation under Grant No. 0638931. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

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