Not everybody is a big fan of being poked with needles to have their blood drawn. But from a medical perspective, blood tests are far less invasive and carry less potential for harm than other diagnostic tools. That's why medical researchers are increasingly hunting for reliable blood tests for serious diseases, like the experimental Alzheimer's disease test we covered last week. And this week, researchers report progress on assessing a new condition: a promising blood test for determining Down syndrome in a fetus.
The technique involves a blood test for the mother and an ultrasound for the baby. From the combined results, doctors can estimate the chance that the baby has Down's. [CBS News]
Down syndrome happens when a baby has an extra copy of chromosome 21. Because the fetus' DNA can cross over into the plasma of the mother, doctors can seek out the extra chromosome in a blood ...
