Brian Skotko, MD, MPP, a clinical fellow in genetics at Children’s Hospital Boston’s Down Syndrome Program, recently wrote a Thrive editorial about a soon-to-be available prenatal test for Down syndrome, which could safely and inexpensively detect whether or not a fetus has Down syndrome during the first trimester of a pregnancy. According to Skotko, once this test becomes widely available it will raise many ethical questions in regards to the already staggering pregnancy termination rates of fetuses with Down syndrome. (Current numbers show that about 90 percent of unborn children worldwide who test positive for Down syndrome are terminated.)
In less than a month’s time the post has been viewed over 8,500 times on Thrive alone, and has lead to debate on Down syndrome websites, Facebook, NPR and now television. Last night Dr. Skotko joined Dr. Lachlan Forrow, Director of Ethics at Beth Israel Deaconess Medical Center, on WGBH’s Greater Boston, to discuss prenatal testing and the effect it will have on both the Down syndrome community and the population at-large.
Written by Brian Skotko, MD, MPP
Children’s Hospital Boston Clinical Genetics Fellow, Down Syndrome Program
Last week a breaking study in the British Medical Journal offered a glimpse into our reproductive futures: soon, a non-invasive test will allow expectant mothers to know whether their fetus has Down syndrome.
Current prenatal tests for Down syndrome are invasive and can potentially cause a miscarriage, making them undesirable for many women. But now scientists have learned how to quantify the fetal copies of the 21st chromosome, the genetic basis for Down syndrome, with a simple blood test taken in the first trimester. These tests would be safer, faster, and, most likely, cheaper than anything available today. …
Traditional genetic testing identifies chromosomal duplications or deletions in about 3 percent of children suffering from unexplained developmental disabilities. Now, using a cutting-edge tool called a chromosomal microarray, physicians can increase that number to about 15 percent – giving answers to potentially tens of thousands more children.
More than 3 percent of children are born with developmental disabilities that have no obvious cause. These children often baffle physicians because medical history and a physical exam are just not always enough to diagnose them. “When we see a patient, we go down our checklist of the usual suspects,” says David Miller, MD, PhD, clinical geneticist in the Division of Genetics at Children’s Hospital Boston. “If we get to a point where we still can’t put our finger on anything, that’s when we turn to this type of testing.”
There are hundreds of chromosome deletions or duplications that result in birth defects or developmental disabilities such as autism. By zeroing in on the exact cause, physicians may be able to determine which specialists need to be added to the team and how best to treat them.