Designing Your Baby. The technology is in place to order up a child’s physical traits or intellect. The issue is how far we want to take it. It started a decade ago with Dolly the Scottish sheep, the world’s first cloned mammal. Then a year later came Lucy the Canadian mouse, the first mammal with artificially implanted genes that could be inherited by her offspring. Since then, the world has expressed a mixture of confusion, horror and optimism at the potential of genetic engineering to prevent diseases in humans and “enhance” physical or cognitive traits.
So where does this technology stand? Are we any closer to creating so-called “designer babies”? And is there a developing darker side in which parents intentionally alter a baby’s genetic makeup so he has the same condition, such as deafness or dwarfism, as his parents?
If the last question shocks you, be clear that a survey published by the medical journal Fertility and Sterility showed that about 3 percent of U.S. fertility clinics—four out of 137 responding clinics that perform embryo screening—already have performed procedures to help couples create children with a disability such as dwarfism or deafness.
First, a few definitions are needed. According to Marcy Darnovsky, associate director of the Center for Genetics and Society, in Oakland, Calif., when people say “designer baby” they often mean different things. Some refer to the ability to select the sex of an embryo; others interpret it as selecting the embryo (fertilized egg) itself. Embryo selection is increasingly used for in vitro procedures when couples are at high risk for certain genetic diseases, such as cystic fibrosis. It allows them to screen out embryos carrying genes associated with the disease.
Most scientists avoid the “designer baby” phrase altogether, preferring “germline engineering” or inheritable genetic modification (IGM), defined as the altering of genes that pass on to future generations. This contrasts with non-inheritable gene therapy, such as when altered genes are added to body tissue, say, a diseased lung, in efforts to improve function.
More Reality Than Science Fiction
Although the technology for doing IGM has existed since 1978, it is now only done in non-human animals. If a scientist, for example, wanted to test a new anti-cholesterol drug on mice, rather than trying to find mice with naturally high levels of cholesterol, he could order a line of mice whose genes had been changed to give them this condition. As of yet, however, the technology hasn’t been perfected. Mistakes often are made in the gene-altering process that lead to developmental abnormalities. This is one reason—and a good one at that—the technology hasn’t been attempted in humans.
But some people advocate developing IGM for use in humans. They see IGM as a way to make life better for their children. And what parent wouldn’t want that?
“None of us want to pass on to our children lethal genes if we can prevent it,” says W. French Anderson, professor of biochemistry and pediatrics at the University of Southern California School of Medicine. “And that's what's going to drive germline gene therapy.”
But this kind of argument is a little misleading, says Darnovsky. The technology already exists today for screening out embryos with “lethal” genes, without adding to or changing the genes of a future child. The technique used for this is called pre-implantation genetic diagnosis. Like in vitro fertilization (for infertile couples), it involves removing several eggs from a woman, fertilizing them with the husband’s sperm, and allowing the embryos to grow to several cells each. Then one cell is extracted from each and genetically analyzed. As scientists continue to unravel the code of the human genome, genes associated with other diseases and other traits will be identified.
Power to Make a Child Taller, Thinner, Smarter
IGM is an even more powerful technology. Proponents of human IGM say that within the next two or three decades it could be possible to use it to prevent cardiovascular disease, slow down the aging process, confer better resistance to viral infections and control variables like height and weight.
Whew. That’s plenty. But further down the road, some say, scientists may be able to control personality traits as well as body forms (tall and thin, stocky and muscular), create genius-level intelligence, even borrow characteristics from other species, for instance an eagle’s telescopic vision or a dog’s sense of smell.
One of the problems with IGM, according to its detractors, is that, despite its great promise of disease prevention, there is a fuzzy line between medical therapy and enhancement. While most people can clearly see the value of preventing an inheritable disease like cystic fibrosis, what about a “condition” like short stature? Should genes be altered to ensure somebody doesn’t end up shorter than his peers, which might cause social maladjustment? If height is an issue, what about skin color or the shape of one’s nose?
Dark Side: Breeding ‘Superior’ People, Wealthier Are Healthier
And this leads into the dark side of the debate. If IGM becomes a reality for humans, it could usher in a new era of eugenics--efforts to “breed” superior people. It could turn children into a commodity whose characteristics could be chosen like options on a car. It might distance us socially even more from the disabled, the sick and the poor especially if only the wealthy could afford to provide genetic engineering for their offspring.
Even IGM boosters believe the high cost of genetic engineering is a pitfall. Lee Silver, a Princeton molecular geneticist who sees a bright future for IGM, told the New York Times that “people with money … will be able to not only give their child a better environment, but also better genes."
At a conference in Denmark, Silver told professional colleagues that if the costs of genetic engineering became affordable to the middle class of western countries, “the already wide gap between wealthy and poor nations could widen further and further with each generation until all common heritage is gone. A severed humanity could very well be the ultimate legacy of unfettered global capitalism."
Darnovsky and many others argue that federal regulations are needed to regulate germline genetic engineering, especially given the widespread public opposition to it.
For instance, a recent poll by MSN-Zogby found that only a third of Americans would approve of the ability to “design” a baby’s traits, and even then only as long as that genetic alteration is for a valid medical reason.
Paradoxically, the United States is practically alone among western nations in not forging strict guidelines or outright bans on the technology. Congress hasn’t followed the European (and Canadian, South African and Australian) model, which bans both human reproductive cloning and IGM. The hangup seems to be on the issue of “research cloning”--using cloning techniques to further research in fields such as stem-cell technology. Powerful lobbying interests believe that if research cloning were limited or banned, businesses would suffer and individual rights (of scientists and, presumably, corporations) would be infringed.
Meanwhile, the United States has become, in Darnovsky’s words, “the Wild West of reproductive technologies.” Like the land of Wyatt Earp and Jesse James, where the laws were few and the sheriffs far between, the U.S. is widely seen as a place where oversight of assisted reproduction is scant.
A Washington Post story last year described how “medical tourists” are visiting the U.S. to select the gender of their next child. The couples are from countries that have bans on using embryo selection technology for non-medical reasons. The U.S. is one of the few countries in the world where this practice is allowed.
Embryos of the desired sex are then implanted in the wife’s womb. One clinic’s Web page gets 140,000 hits a month from China, where most couples prefer boys. Clients from other countries, such as Canada, seem to favor girls. Opponents say the practice reinforces sexism and could lead to the practice of using genetic engineering to select desirable physical traits, which critics say veers toward eugenics.
Last year, a survey of U.S. fertility clinics found that a few had used the trademarked Pre-implantation Genetic Diagnosis to select embryos with what most people would call genetic defects: deafness and dwarfism. Although these traits may be considered defects to those who don’t have them, they’re the norm for people who do. These traits may be so vital to their identity and culture that they want their offspring to share them. And a few, apparently, are willing to pay the $15,000 cost per cycle of trying to conceive a child who shares their unusual features.
The “designer baby” issue is still under the radar of most people, says Darnovsky, because more press is given to the related technologies of cloning and stem cell research. Yet she thinks that “germline engineering is the most dangerous of all these technologies.” If it is developed and used, it could have dire consequences for society.
She compares the germline engineering debate to sailing a boat down a narrow channel in choppy water. On one side of the channel are people who oppose abortion rights because of their belief in the moral sanctity of human embryos, and who therefore think we shouldn’t be manipulating or selecting them. “On the other side is an equally serious danger from people who have an ‘anything goes’ mentality toward these technologies,” she says. These are the scientists and businessmen and futurists who see a huge need and market for “improving” the human race. In their minds, there should be no limits on a couple’s right to choose the kind of baby they want, or a corporation’s right to pursue a profit.
Somewhere in the middle of the channel is where a solution lies, Darnovsky believes. There should be controls, but without dampening research that would help people medically. There needs to be a lot more public discussion of the issues.
“Sometimes people express unease about genetically redesigning our children by saying that we shouldn’t play God,” she says. “I think these concerns may have more to do with the ‘playing’ than with the ‘God’ part. Should we be manipulating human biology and society like this? Technically and socially, do we know what we’d be doing?” ( msn.com )
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