Our gentle descent toward eugenics.
The most important shift in the HFEA decision is that the lines being drawn in each of these areas—probability, treatability, and age of onset—are increasingly subjective. The HFEA's "Code of Practice" says "PGD will be available only where there is a significant risk of a serious genetic condition." However, the code adds, "The perception of the level of risk by those seeking treatment is an important factor in the decision making process." In its current report, the HFEA says this rule fits the view that "significance is something that only the person at risk can determine." A significant risk is whatever you say it is.
You don't even have to establish the probability or gravity of a physical disease. Your fear of disease is grounds enough. "Carrying the faulty gene can cause significant anxiety which is not lessened by the fact that the condition is not fully penetrant," says the HFEA. Its chairwoman, Suzi Leather, says the agency is loosening restrictions on PGD in part due to "the extreme anxiety that carriers of the gene can experience."
Leather assures us the new policy won't lead to eugenics. She says the HFEA is allowing PGD only for diseases for which "we have a single gene test. … We would not consider conditions like schizophrenia where a number of genes have been identified." But if the gene you're weeding out correlates with a disease only 30 to 80 percent of the time, there's every reason to suspect that other genes are involved. By targeting that disease, you've crossed the single-gene line.
"We would not consider mild conditions—like asthma and eczema—which can be well-managed in medical practice," says Leather. But if significance is subjective and anxiety is sufficient, won't some parents feel that severe asthma meets that standard? As for Leather's assurance that PGD "can still only be used for a minority of people if there is a clear history of cancer across generations of a family," why should anyone respect that line? Once genetic testing becomes cheap and universal, why shouldn't anyone who finds out she has a cancer gene be able to test her embryos for it?
The HFEA calls its report "Choices and boundaries." In a democratic gesture last fall, the agency told the public, "We would like to understand where people feel the limits—or boundaries—of this technology should lie." But in its internal briefing paper, the agency says it had "no intention following this discussion to define limits for conditions that should not be tested for using PGD." Mission accomplished.
Will Saletan covers science, technology, and politics for Slate and says a lot of things that get him in trouble.
Photograph of human embryo on the Slate home page © Clouds Hill Imaging Ltd./Corbis.