A Nobel laureate holds forth on flies, genes and women in science
Christiane Nüsslein-Volhard, pioneering geneticist and co-winner of the 1995 Nobel Prize in Physiology or Medicine, recently published her first book for a popular audience. Coming to Life (Kales Press) explains the genetic and cellular basis of animal development and explores the ethical implications of recent progress in genomics and biotechnology.
One of only 12 women Nobel Laureates in the sciences, Nüsslein-Volhard grew up in post-World War II Frankfurt, Germany, where she was an undisciplined student whose high school teachers described her as "decidedly lazy." But she had a gift for science, and in 1975, after earning a PhD in molecular biology, Nüsslein-Volhard began what would become a landmark study of genetic mutations in the fruit fly drosophila. "I immediately loved working with flies," she says. "They fascinated me and followed me around in my dreams." She and colleague Eric Wieschaus identified the key genes responsible for embryonic development in drosophila and amassed a detailed catalog of mutations that cause physiological defects—insights that help scientists better understand human development. Today, Nüsslein-Volhard is the director of the Max Planck Institute for Developmental Biology in Tübingen, Germany, and heads the Christiane Nüsslein-Volhard Foundation, which supports women scientists with young children.
Why did fruit flies follow you in your dreams?
I had been a biochemist before coming to genetics, and there is nothing really to look at in biochemistry. But the flies were living animals and embryos—I saw them whenever I closed my eyes.
It took you a while to find this passion for developmental biology. If you started your career today, would it be any easier?
I think it would be easier. The consciousness about women in science, for example, has changed dramatically from the time I was a student. Nobody thought about it at all then. The general expectation of course was that one would marry and have children, and I think this pressure was stronger then.
Why is it still so hard for women to reach the highest levels of scientific professions?
It's very hard work, you know, it really is hard work, and it requires that one be single-minded, because these jobs demand so very much of your time. I think women do not really like that so much, and often you observe that they're less ambitious, that they're easier to intimidate. I'm not sure why. I think there are profound differences between women and men. In intelligence and creativity there is no difference, but in what one loves, what one likes, the passions—there are differences.
Do you think it goes back to the conflict between work and family?
Not completely, but I think that it's tough for many parents. And there's a lot more work for mothers than for fathers, because the women have the children, and they also do much more for them when they are very small. That's the concern of the Foundation—not so much to encourage all women to take interest in the sciences, but to make life easier for women who are already there. Then in ten years or so more women might be scientists.
Who should read this book? Would President Bush or the German chancellor, Angela Merkel, benefit from knowing more about developmental biology?
Yes, I think that if they could understand the science, it might clarify the issues surrounding stem cells and embryonic research a little. Although they would probably not have time to go through the whole book.
So if they did read it—or if they had their assistants summarize it for them—what lessons would you want them to take away?
The most useful thing they could learn: that they shouldn't be so afraid of this modern knowledge. People think if you have deciphered the genome of humans that you can change everything. But you cannot change everything, because you do not know what the genes mean, and you have no methods for changing them, and you can't do experiments with humans like you can with animals. And therefore it's totally unrealistic to have fears about this.
In the book you talk about the importance of discriminating between science fact and science fiction—we aren’t headed toward Brave New World.
Yes, designer genes and cloning will never work. There is a difference between principle and practice. You might say, "Well, they have a technique which works now," and this is true, you can make a cloned sheep, and you can make a cloned cat—but in humans it will never work. Humans are something very different from animals, and the numbers required to get cloning to work in animals are completely prohibitory with humans.
Are the possibilities of stem cells exaggerated as well?
Some people think that whenever you find something you will cure this disease or that disease—when scientists find an enzyme that prolongs the life of a worm by a couple of days, then they say, "This is something! We will live forever!" And of course it's not true. People exaggerate these findings so much, and they do it because they think they will get more research money. But you cannot just buy a treatment by putting more money into a particular field. It works differently—it works more by chance. You have to have a good grounding and have good ideas and be well-educated and do interesting things, and then every now and then something will pop up—but you cannot push too hard! You cannot say, "This must work now!" If you want to climb a mountain, often the direct way is not the right way, often it's better to go in circles.
Will there be breakthroughs within your lifetime?
You get answers all the time, of course, small answers to big questions. But big breakthroughs, I don't know.
What is the biggest question in biology?
Understanding evolution, how animals and plants and organisms evolved and formed shapes and adapted to different environmental conditions—I think that's fascinating, and we have very good theories, but the exact path is not really very well known. We also don't really know how diversity arises, how we get new species and this enormous diversity in shape and form.
Is that what you're working on now?
Yes, that's much of my research, how you get diversity. When you compare genes from different animals, you find very similar genes in worms and in flies and in humans, and this doesn't really explain how they got different. And I want to know why.
Are you still working with drosophila?
We are now mostly working with zebra fish. There is great variation in fishes, and if we can understand it in fishes then perhaps we can also figure out the differences in mammals. And it's much easier to work with fishes than with mammals.
Why is it easier to work with fish than, say, mice?
Mice are live-bearing, and their embryos are small and you can't look at them. Fish lay clear eggs and you don't have to kill the mother in order to look at the babies, which you have to do in mice.
How many fish do you have right now?
We have about 10,000 aquaria. It's a big house with five rooms. And the total number of fish is probably 500,000.
And do you ever have dreams about the fish?