Unnatural selection?
How far will parents go? A group of ethicists fear that genetic science will soon make it possible for couples to customise their offspring down to intelligence levels and even the length of eye lashes…
Picture this: prospective parents excitedly clicking through an online catalogue, ticking off the optimal mix of traits for their yet-to-be-conceived child.
Will they opt for blue eyes or brown? Perhaps green, for a touch of originality? What colour skin? And do they want a boy or a girl?
Are they aiming for an Olympian athlete, or will they stack the deck in favour of intellectual prowess? Why not both?
For some people, this would be a dream come true. For others, a nightmare of widening inequality touching on eugenics.
For biologists, it raises acute questions about evolution. And no, this vision clearly does not belong to the hazy future of science fiction…
Of Freckles and long eye lashes
Dozens of clinics in the United States – one of the least regulated markets for fertility services – already provide would-be parents in-depth profiles of potential sperm and egg donors.
Atlanta-based Xytex Corporation, for example, offers a long list of genetically-coded physical attributes, right down to the length of eyelashes, the presence of freckles and whether ear lobes are detached.
There is also a summary of the donor’s medical history and – for an additional fee – personality and educational profiles, a personal essay and photos, as an adult and a baby.
Much of this information has no relation to genetic pedigree and even when it does, the result – a human child – may not come out as advertised. But that has not dampened enthusiasm for the tests.
Most couples shop in this market to compensate for either male or female infertility.
But there is nothing – in science or, in some countries’ law – to prevent matching a donor egg with donor sperm to create an embryo that can be purchased and implanted in the buyer’s womb.
This option was offered by at least one “embryo bank” in Texas before it reluctantly withdrew the procedure under an ethical firestorm.
Even parents who don’t need outside help to procreate may soon be clamouring for “preimplantation genetic diagnosis” of embryos to check not only for genetic defects and disease – the original intent – but also for sex and desirable traits as well, experts say.
“We need to look carefully at these selection technologies,” said Marcy Darnovsky of the Centre for Genetics and Society in Oakland, California.
“It is not bad to have a desire for a girl or a boy,” she said. “But what are parents going to do if they don’t get the kind of kid they asked for. Would they take her back?” she said.
A new human species?
An even more problematic scenario for some is the leap from genetic selection to genetic engineering. “The pressure to change genes will probably come from parents wanting to guarantee their child is a boy or a girl, or to endow them with beauty, intelligence, musical talent or a sweet nature,” notes Peter Ward, a scientist at the University of Washington and author of Future Evolution.
For now, germ-line therapy is out of reach. But were science to master the genome, the temptation to tweak it to increase smarts, looks and longevity would be overwhelming, Ward argued last month in the journal Science.
“One day, we will have it in our power to bring a new human species into this world,” he said.
Not all researchers agree, however. “I think that all of these worries are misplaced – genetics is far too complex to allow for easy manipulation of human traits,” said Steven Pinker, an evolutionary biologist at Harvard University.
Nearly all diseases and traits are determined not by one or two genes but the interaction of many, he pointed out. There is no such thing, in other words, as a master gene for intelligence or musicality.
“I doubt that parents would take a risk greater than five per cent that something would go wrong,” he said. “Testing is easy and safe. Manipulation is hard and risky.”
genetic science is much forword..
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