What Should Geneticists Do When They Find Out Family Secrets?

  • 2017-05-16
  • Aeon

Sequencing the first human genome took more than a decade and cost billions of dollars. Nowadays, an individual’s genome can be sequenced in days for as little as a thousand dollars. The plummeting cost of genomic testing has made its use in medical research routine. Genetic information is collected in studies of cancer, HIV, diabetes, schizophrenia and pretty much any disease you can think of. Yet in the course of sequencing the genomes, researchers investigating diseases that can run in families sometimes discover that parents and children who thought they were genetically related are not. Such findings usually manifest as misattributed paternity resulting from infidelity, but they can also arise when children don’t know they’re adopted, or even because of a mix-up at the IVF clinic.

Should people be told the truth about their biological parentage?

Scientists who think it unethical to withhold the information might emphasize the possible benefits of disclosure. Someone with an undiagnosed disease might realise that answers would not be found in her parents’ medical history, and might instead track down her biological family to discover whether her condition affected them too. Couples might make better reproductive decisions if they knew that they were not, after all, at risk of passing on a genetic disease. And we might think that just knowing the truth about one’s ancestry is preferable to living a lie.

But disclosure also has potentially negative consequences. In the first place, discovering misattributed parentage is likely to cause distress. For some people, genetic relationships are a vital part of identity. Family resemblance can be a way of belonging – your father’s eyes, your mother’s wit, your grandfather’s crinkled smile. Some people see themselves reflected in their family members, and locate themselves within histories whose actors are important because of their presumed biological links. Moreover, if the misattributed parentage resulted from infidelity, it might disrupt family relationships and even lead to violence.

Along with US National Institutes of Health bioethicist Ben Berkman, we’ve argued that researchers could disclose the information selectively but, that once it was out there, there’d be no way to control how it was then used. How is a researcher to accurately assess the potential for domestic violence? How could she predict the extent to which someone’s identity is tied up in his genetic history? How can we put a value on someone knowing the truth?