Down syndrome already poses difficult questions: It has no etiology of disease, but its mutation comes with higher risk factors for a number of potential health problems, and the condition usually entails mild to moderate developmental and cognitive delays. How do parents choose whether or not to parent a child whose future would be so uncertain? With the future of sequencing getting cheaper and more refined, which fetal genetic traits will be deemed acceptable, and which will not?

2013 also saw the death of Adrienne Asch, a disability studies scholar and head of the Center for Ethics at Yeshiva University. Asch was a rare thinker, willing to engage the thorny issues that arise in vigorously supporting both reproductive freedom and disability rights. Blind from just after her birth, she was outspoken in her defense of abortion rights for unwanted pregnancies and in her conviction that prenatal testing, when used to identify and selectively abort fetuses with a genetic mutation that results in a condition such as Down syndrome, preemptively and wrongly interprets a life with disability to be a tragedy, a life not worth living.

Together with philosopher David Wasserman, Asch wrote in 2005 that using genetic tests to screen out a fetus with a known disability is evidence of pernicious “synecdoche.” Ordinarily, synecdoche is a value-neutral figure of speech, in which some single part stands for the whole—as in the common use of "White House" to stand for the executive branch of government. But Asch and Wasserman’s meaning was more loaded: prenatal genetic tests, they argued, too often let a single trait become the sole characteristic of a fetus, allowing it to “obscure or efface the whole.” In other words, genetic data, once known, generally become the only data in the room. Taking a “synecdochal approach” to prenatal testing, Asch and Wasserman warned—in the era just prior to consumer genetic sequencing—allows one fact about a potential child to “overwhelm and negate all other hoped-for attributes.”

And isn’t synecdoche partly what’s plaguing the narratives about consumer genomic technologies in general? An easy conflation of fact with insight, of data with understanding: the part standing in for the whole. The FDA cracked down on 23andMe because of its confident claims that genetic sequencing could provide some reliable probabilities for its consumers’ future health. But the science isn’t there yet: Our access to this genetic information far, far outpaces our ability to understand it. The links between a genetic marker and any certainty about future health or sickness can’t be made in such one-to-one fashion. And yet: Genetic data continue to wield a stronghold on the public imagination, as though these facts alone unlock mysteries from which any of us, armed with a swab kit and a couple hundred bucks, can make substantive, predictive meaning.

We won’t know what Asch would have made of 23andMe, designer babies, or broader claims for personal genomics. But her intellectual legacy only grows more relevant in the era of ever-cheaper, personalized genetic data. Asch understood that there are plenty of things technologies like prenatal genetic testing can tell us. But the choices and challenges in defining a life worth living, and living well—it may be that these aren’t technological problems at all.

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