Prenatal DNA Sequencing
Professor Hank Greely spoke with Antonio Regalado from MIT Technology Review about whole-genome sequencing and why he believes it could open "Pandora's box."
Earlier this year Illumina, the maker of the world’s most widely used DNA sequencing machines, agreed to pay nearly half a billion dollars for Verinata, a startup in Redwood City, California, that has hardly any revenues. What Verinata does have is technology that can do something as ethically fraught as it is inevitable: sequence the DNA of a human fetus before birth.
Verinata is one of four U.S. companies already involved in a rapidly expanding market for prenatal DNA testing using Illumina’s sequencers. Their existing tests, all launched in the last 18 months, can detect Down syndrome from traces of fetal DNA found in a syringeful of the mother’s blood. Until now, detecting Down syndrome has meant grabbing fetal cells from the placenta or the amniotic fluid, procedures that carry a small risk of miscarriage.
The problem is that having more information about a fetus’s traits could present doctors and parents with a deluge of information they aren’t able to understand or act on. And if they do act, that could be controversial, too. “Whole-genome sequencing could open Pandora’s box,” says Henry Greely, a law professor who studies bioethics at Stanford. “You’d have the whole sequence, so you might be able to look for straight nose, curly hair. How many parents are going to abort a fetus because of male pattern baldness? I don’t think many. But it’s probably more than zero.” Greely says that because fetal DNA is detectable in the bloodstream so early in pregnancy—as early as six or eight weeks—the pregnancy could be ended relatively easily.