…geneticists also pointed out that companies’ marketing materials make it seem as though the tests are infallible. As the testing firm Sequenom puts it in one advertisement: “Positive or negative results. Never maybe.”

[…] For Solomon, genetics is simply a new tool with a learning curve, the same as any other. “When the electrocardiogram was first developed, about a hundred years ago, most physicians thought it was voodoo,” Solomon said. “Now, if you don’t understand it, then you shouldn’t be practicing medicine.” But Mary Norton sees that analogy as too simplistic. The pace of genetics research, the variability of test methods and results, and the aura of infallibility with which the tests are marketed, she told me, make this advance a more complicated one than the EKG. Norton believes that, as genetics becomes increasingly integrated into medical care, “over time everyone will come to have a better understanding of genetics.” But, as the demand for DNA testing increases, she says, “it will probably be a bit worse before it gets better.”

From: The Problem with Precision Medicine, by Cynthia Graber, The New Yorker,  February 5, 2015: http://www.newyorker.com/tech/elements/problem-precision-medicine