Scientists are closing in on a 100% accurate,  non-invasive test to detect Down Syndrome children so that they can be aborted early in a pregnancy. Andrew Pollack, of the New York Times, highlights two of them. One, developed by a San Diego company, Sequenom, will go on the market next year. The other is being developed by Stanford University. Both are still in the early stages, but so far the results are impressive: no false positives and no false negatives.

The problem with Down Syndrome tests at the moment is that at least two are required and the second can cause miscarriages. As a result, healthy babies also die. There are various estimates of how often this happens. The figures cited by the Times suggests that 10 Down Syndrome children would be aborted for every miscarriage of a healthy child. However, a report earlier this year in the Down's Syndrome Research and Practice journal, based on UK data, suggested that for every three unborn Down's syndrome babies aborted, two healthy babies will be miscarried. 

However large the problem is, it is a problem and an accurate test will be a popular product. Even though both tests still need to be trialled, the price of Sequenom’s stock has quadrupled since March.

Advocates for Down Syndrome children are alarmed by the tests. They say an easier test will eliminate people with Down syndrome and make it harder to get social support. However, most people are likely to agree with an editorial in the New Scientist which argued that the tests would take stress off parents: “Existing tests are medieval... Most importantly, [new procedures] will offer more parents a choice, and one that is not complicated by hazardous tests.” ~ New York Times, Oct 6; New Scientist, Oct 8