...Yet Susannah A. Baruch and colleagues at the Genetics and Public Policy Center at Johns Hopkins University recently surveyed 190 American P.G.D. clinics, and found that 3 percent reported having intentionally used P.G.D. “to select an embryo for the presence of a disability.” In other words, some parents had the painful and expensive fertility procedure for the express purpose of having children with a defective gene. It turns out that some mothers and fathers don’t view certain genetic conditions as disabilities but as a way to enter into a rich, shared culture.