New Noninvasive Prenatal Test Raises Enormous Ethical Issues
By Dave Andrusko
“What if you could read much of your child’s medical future while it was still in the womb? Taking a major step toward that goal, one fraught with therapeutic potential and ethical questions, scientists have now accurately predicted almost the whole genome of an unborn child by sequencing DNA from the mother’s blood and DNA from the father’s saliva.”
—From “Sequencing the Unborn,” Science Now
Publishing in the journal Science Translational Medicine, researchers at the University of Washington say they have found a new noninvasive procedure that may allow women someday soon to test their unborn babies for more than 3,500 genetic disorders. How far off this may be is speculation, but the researchers seem to think within five years, others much further down the line.
The team pieced together the entire genetic profile of an unborn baby only 18.5 weeks after conception by taking plasma from the mother and a swab of saliva from the father.
“They then reconstructed the genetic code of the unborn baby, then tested the accuracy of the results by using umbilical cord blood after the baby was born,” ABC News reported. The method was repeated in another couple on a younger baby (8.2 weeks after conception), a time when less fetal DNA is in the mother’s blood.
“The primary significance of this is that … it may broaden the availability of genetic screening to more patients, while at the same time screening for much larger panels of disorders than can currently be detected,” said Jacob Kitzman, who worked on the project.
The lead scientist, Dr. Jay Shendure, said, “This work opens up the possibility that we will be able to scan the whole genome of the fetus for more than 3,000 single-gene disorders through a single, non-invasive test.”
Added Kitzman, “The improved resolution is like going from being able to see that two books are stuck together to being able to notice one word mis-spelled on a page.”
Although not emphasized in most stories, this technique is building on something that is currently available on the market. There are already tests that “take advantage of the fact that there’s DNA circulating from the fetus in a mother’s blood,” according to NPR’s Rob Stein. These tests are much more specific, he explained.
“They don’t analyze the entire genome,” Stein told NPR’s Audie Cornish. “They don’t spell out every single letter in the genetic code. They look for very specific variations, usually things like Down syndrome and conditions related to that.”
Put another way, the same search-and-destroy test that potentially targets babies with Down syndrome will someday be available to find some 3,500 genetic disorders.
ABC News addressed the abortion implications straight on in its story:
“When the time comes for the procedure to be used in a clinical setting though, Kitzman said clinicians would face the challenge of interpreting these results and communicating them with expectant parents—both the results themselves and the uncertainties that come with them. While these advances will help better understand risk factors for illness, [bioethicist Art] Caplan predicted ‘they will be among the most controversial forms of testing ever to appear in medicine as the debate over abortion and disabilities both shift to whole genome genetic testing.’”
Bioethicist Wesley Smith is strongly critical of the new test. Writing on his blog, Smith observed, “This test, if it comes to pass, will not only be used to eradicate children with Down, cleft palate, and dwarfism—as already happens—but also the propensity for adult onset cancer. Oh yea, that already happens with embryo screening.”
Smith added, “The list of abortion excuses could spread into cosmetics, hair and eye color, height, propensity to weight gain, the list could go on and on.”