By Allysia Finley
Scientific breakthroughs are sometimes a matter of serendipity. Eight years ago Meredith Halks-Miller, a pathologist at the genetic-screening company Illumina , stumbled on something unusual while running prenatal blood tests for fetal chromosomal abnormalities. In some blood samples, the fetal genes were normal but the maternal DNA wasn’t. Illumina alerted pregnant women’s doctors to the finding. After further investigation, all the women were diagnosed with cancer, though none had symptoms when their blood was drawn.
This discovery led to the development of a blood test that can now detect 50 types of cancer and has the potential to save tens of thousands of lives a year if it becomes widely available. But regulators may slow the process.