The sequencing of the human genome a decade ago unleashed a deluge of information that seems unlikely to abate any time soon — and which some medical professionals need to do a better job keeping up with. In the last three years, there has been an explosion of interest in a new generation of prenatal screening tests — done through a simple blood draw — designed for high-risk women who want to know whether the fetus they are carrying has Down syndrome or other chromosomal abnormalities. But this new industry must do a better job educating patients and doctors about what test results mean.
While new technologies are often rightly embraced because they propel medicine forward, these testsshould always be accompanied by genetic counseling along with complete, easily accessible information about accuracy and risk. As a recent report by the New England Center for Investigative Reporting carried by the Globe found, the tests, which are 99 percent accurate, do result in false positives, so the results must be followed up with a gold-standard diagnostic test like amniocentesis.
It is far from reassuring, however, that the US Food and Drug Administration has gotten involved. In September, the agency published draft regulations that are expected to take nine years to be phased in. This is overkill. Screening test results are already produced in labs regulated by CLIA, or Clinical Laboratory Improvement Amendments, which requires strict standards for testing human samples. Advocates for the labs recommend a wiser course: making a few changes to CLIA regulations that would address the questions raised by the FDA. Non-invasive prenatal screening has a valid place in the physician’s toolkit — so long as the results are properly understood.