Since the first personal genetic tests became available on the Internet three years ago, critics have raised concerns about their potential impact on patients and families, along with their accuracy. Some say that the tests are "genetic horoscopes," and just about as scientific. Such misgivings have led to personal genetic tests being banned in several US states, as well as in European countries like France and Germany.
Personal genetic tests vary from one manufacturer to another. At one end of the market, there are companies offering to test for recessive red-hair genes or sexual chemistry. A firm called Scientific Match tests a small number of genes related to immune response, promising that it can put you in touch with partners whose genetic make-up will promise you a better sex life and your children a high natural immune response. At the other end of the spectrum, firms like Navigenics and 23andMe offer tests for genetic predispositions to a range of medical conditions like Alzheimer's disease, breast cancer, and diabetes.
