A New Era of Designer Babies May Be Based on Overhyped Science

Mon, 12 Jul 2021 03:45:00 GMT
Scientific American - Science

Genetic testing with IVF is being marketed as a means to choose a healthy embryo, despite questions...

The company offers prospective parents genetic testing prior to conception to calculate risk scores estimating their own likelihood of confronting common illnesses such as heart disease, diabetes, and schizophrenia and the likelihood that they will pass such risks along to a future child.

Initially, the only people offered tests to prevent genetic disease in the next generation were those whose ancestry put them at higher risk for a specific condition, such as Tay-Sachs disease in the Ashkenazi Jewish population.

According to its promotional materials, the company will provide a scorecard intended to identify, among various embryos, the future children least likely to develop heart disease, breast cancer, prostate cancer, type 1 or 2 diabetes, and five other conditions that make up Orchid's current common disease risk portfolio.

With a marketing strategy that encourages routine use of IVF for those who can afford it, Orchid breaks new ground in introducing the first-but likely not the last-consumer-driven model of human reproduction.

Geneticists have greeted Orchid's launch with skepticism, in large part because of objections to the company's use of a technique called polygenic risk scores to assess an embryo's lifetime risk of common diseases.

"Something that's associated with a decreased risk of breast cancer could be associated with all other kinds of things, some of which might actually increase your risk of something else. We just don't know enough yet."

A July 1 special report in the New England Journal of Medicine pointed out the inherent weakness of using polygenic risk scores to distinguish among sibling embryos-which, unlike random individuals in a population, will be identical in 50 percent of the genetic variation that is examined to generate a score.

Alicia Martin, an instructor at Massachusetts General Hospital and the Broad Institute of the Massachusetts Institute of Technology and Harvard University, says her research examining polygenic risk scores suggests "They don't transfer well to other populations that have been understudied." In fact, the National Institutes of Health announced in mid-June that it will be giving out $38 million in grants over five years to find ways to enhance disease prediction in diverse populations using polygenic risk scores.

Orchid dismisses suggestions from detractors that its marketing oversells what polygenic risk scores have to offer in the context of screening embryos.

Ultimately, if technology allows Orchid to offer a product that meaningfully reduces the risk of disease susceptibility in the next generation, does that mean that anyone who can't or won't use it deserves their bad luck? If the basic, no-frills version of human reproduction comes to be seen as a form of careless parenting, it invites a callous parsing of who does and does not deserve their fate-and, by extension, who does and does not deserve resources and support.

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