Why screening DNA for ‘designer babies’ probably won’t work
Picking embryos based on genetics might not give prospective parents the “designer baby” they’re after. DNA predictions of height or IQ might help would-be parents select an embryo that would grow into a child who is, at most, only about three centimeters taller or about three IQ points smarter than an average embryo from the couple, researchers report November 21 in Cell. But offspring predicted by their DNA to be the tallest among siblings were actually the tallest in only seven of 28 real families, the study found. And in five of those families, the child predicted to be tallest was actually shorter than the average for the family. Even if it were ethical to select embryos based on genetic propensity for height or intelligence, “the impact of doing so is likely to be modest — so modest that it’s not likely to be practically worth it,” says Amit Khera, a physician and geneticist at the Center for Genomics Medicine at Massachusetts General Hospital...