Robert Goldberg: Seeds of Contention
UCLA molecular biologist Robert B. Goldberg wants to understand in plants what stem-cell researchers want to understand in humans: How the undifferentiated molecules of a seed develop from nearly identical dabs into highly specialized plant parts. A decade ago, his pioneering process for turning off a plant’s ability to pollinate led to new, higher-yielding hybrids. Now, Goldberg’s lab, in partnership with other university researchers, is poring over plant DNA in a quest to find the genes necessary to assemble seeds from the raw material of life. He spoke recently about why his own research--and that of human geneticists--is controversial.
Question: The battle over stem-cell research lately has focused on religious and ethical notions of when life begins. Your work modifying plant life has sparked its own backlash. Why the anxiety over genetically modifying life?
Answer: There’s something mystical about nature. Plants have been designed by nature, and we shouldn’t alter nature. For some, it’s God’s plan.
Q: But hasn’t man altered the world inexorably from the first time somebody stuck a kernel of corn into the ground?
A: Absolutely! Food is an easy target, because in the West, we don’t really need genetically engineered food. We can produce most of the food we need by conventional means. That does not mean that we don’t need an abundance of food to feed the millions of people still starving around the world today, let alone the 10 billion people who are going to be on the face of this Earth in the next 50 years. That is a daunting task, and we’re going to have to do it on a shrinking amount of agricultural space unless we want to tear down every forest on the face of the Earth. If we want to be able to grow the best plants that are optimized for human health and for human nutrition, we have to use the absolute best technology, which includes genetic manipulation, something mankind has been doing through selection and cross-breeding for 10,000 years.
For affluent Westerners--who don’t have to worry about standing in line for food, who use only 10% of their disposable income on food, who can afford to pay $4 a pound for organic tomatoes--food is not much of an issue. We’re not faced with the kinds of choices that someone in Africa or Asia, or in parts of Latin America are forced to face: 80% to 85% of their disposable income goes for food, and not having food and not producing a crop is a matter of life or death.
Q: Do we suffer from tunnel vision?
A: The opponents of genetically modified (GM) foods don’t make the scientific connection. The exact same technology that we’re using for plants we’re using for medicine. When someone takes a drug that keeps him alive, that drug--tPA, insulin, growth hormone--was probably created with the same exact gene-splicing technology. People will never argue that we shouldn’t make gene-spliced drugs. Yet, genetic engineering of plants could potentially save millions of lives, in parts of the world that depend on the latest technology in order to be able to live on a daily basis. Will genetically engineered plants eliminate starvation and hunger? No. But it’s one tool in the toolbox that we need to be able to use.
Q: What about the environmental or health risks of genetically modified foods?
A: There’s not one case, not one example, not one shred of credible scientific evidence indicating that anything that we’ve done in the manipulation of plant material or the making of crops has been harmful to humans. This technology is old technology. Genetically engineered plants have been around for 15 years or more. We’re talking about herbicide-resistant (Monsanto’s Roundup Ready) soybeans. We’re talking about insect-resistant corn and cotton. They’ve been tested and retested. I don’t think any plants on Earth have been under more scrutiny than these plants. There’s absolutely no question about it--as opposed to any of the supplements that you can buy at a natural-foods store, which have never been tested, are completely unregulated and you have no idea what active ingredients they contain.
Q: What of the worry of creating a Brave New World of super-insects and super-weeds that resist all forms of insecticide or herbicide? Doesn’t the current decline of the usefulness of many antibiotics provide a proscriptive warning? In other words, technological solutions don’t always provide absolute solutions.
A: I think that antibiotics provide a good illustration. If someone had said at the time of the discovery of penicillin, “Oh, you have an antibiotic and it destroys that particular bacteria, therefore, we might get resistance in humans, so we’re never going to use that to be able to cure human beings,” look at how many millions and millions of people would be dead today. And how much suffering we would have had because that antibiotic wasn’t used. I think one can make a similar analogy with GM foods. It’s just the first step of being able to use these technologies to help people. As with antibiotics, you learn. You learn that it’s overprescribed and you have to learn how to manage it.
Q: What lessons can we learn from stem-cell research?
A: I think the real issue is: Do we want to be exploring the unknown? That’s what scientists do. We ask how the real world works in the biological or physical sense. To understand the process of differentiation, whether it’s how a little seed develops into an oak tree or how an egg and sperm unite and develop into an incredible human being, is a process of knowledge-seeking. We’re nowhere near understanding this process. Maybe we’ll understand it a thousand years from now. Maybe we’ll understand it a hundred years from now. But it can only be learned by studying stem cells.
Q: So all the talk about cloning humans or replacement parts is what?
A: Hype, if you’re talking about a new liver, a new heart, a new kidney. Sure, maybe 50 years from now we’ll do those things, but, right now, the research is more about how stem cells form a line that makes, for example, skin in a mammal. And that question is very similar to the questions we address in my lab. How does a plant make a leaf? How does it make a root? These are very legitimate, important, groundbreaking, frontier questions. These are the mysteries man has been investigating with primitive tools and complex tools for all of our existence. And stem-cell researchers are just trying to take our understanding of the process of development one step further.
Q: Nearly everyone agrees that great strides in medicine are on the horizon, due to stem-cell research. So why all the fear?
A: It’s the perception that human beings are different.
Q: Aren’t we?
A: In a social context, yes. In terms of intelligence, we absolutely are. But in terms of biology, there’s not that much that’s special about us, other than perhaps our complex brains. In terms of developmental biology, stem cells from a human basically do the same things as stem cells from a mouse or a cow or a pig or a goat.
Q: So the fear is?
A: Of playing God. I think it’s important to respect those fears, but it’s also a slippery slope. Things that were considered unethical 30 years ago, like in-vitro fertilization, are now well accepted. Still, one has to separate studying stem cells to understand how they have the capacity to form different organs and tissues and cells in the human body from using those stem cells to make organs or clones. We live in the era of genomics--the sequencing of the human genome, of plant genomes--and we are trying to find the basic mechanisms of disease. For example, eventually we will learn how to make better antibiotics that really might not even be antibiotics--that might prevent bacteria that cause pneumonia from even infecting us. That, in truth, is where stem-cell research is taking us.
Q: What about cloning?
A: I think people are afraid that we’re going to have this super-human race.
Q: Eugenics.
A: Exactly. And that’s an important issue. Nevertheless, it’s important to point out that we do clone human beings. They’re called twins, and triplets, and quadruplets, and sextuplets. But they’re not the same human being. They interact with their environments in very different ways, and they have their own unique potential. So, I think the kinds of fears that one thinks about in terms of building a super-race are based on non-science.
That said, I can see certain circumstances where people might want to clone, not themselves, but maybe to have stem cells that have the same genetic constitution as themselves. What could be better than to be able to replace a liver that has given out with a new liver? What could be better than having someone who has children stay alive rather than having them suffer some premature death because of kidney failure or heart failure? I think that in 50 or 100 years--I can’t put a time framework on it--people will look back and say it was a good decision to clone.
Q: Now that we’ve sequenced the human genome, what more do we have to learn about genes?
A: There are many genes in us and in plants and in other creatures that are duplicated and tripled, and there are genes that compensate for another gene when it’s lost. What we don’t really know is how a lot of these genes work together; that’s one of the great problems many of us are exploring. How do thousands of genes work together to make a plant or make an oak tree or make a human being? Our cells work as one; all the genes in that cell work as one. There’s not a single one of them that’s working by itself.
Q: So no gene is an island?
A: I think all complex organisms function holistically. We can understand how single genes work. We can understand how several genes work together. But these things work together with millions of proteins and millions of other things, and we haven’t even begun to grapple with the complexity of how one single cell works in its totality, let alone the trillions of cells in a human body. There will be new rules that will surprise all of us, and these things are going to come out of basic research, which is why basic research is so exciting.
