You can be anything you want to be. That’s what parents, teachers and youth leaders have been telling children for years: Even if little Bobby wants to be a major-league shortstop, there’s a chance he could—if he works really, really hard at it. Some worry that genetic testing may mark the end of that sort of optimistic thinking. A number of companies are now marketing genetic testing to parents—tests that will help determine a child’s predilection to excel in a given sport. The tests are simple: Just rub the inside of a child’s cheek with a swab, stick the swab in the mail and, for less than $200, the company will judge what sports or activities the child likely aptitude for a particular sport. Kids who have the ACTN3 gene, for instance, might have more explosive musculature than kids without it, theoretically making them more adept at a whole host of sports. Critics caution sports success isn’t just a matter of genes. About 80 percent of children have the ACTN3 gene, for instance, and only a few go on to become superstars. Some world-class athletes have gone on to excel without it. “This is recreational genetics with a real serious potential for harm,” Dr. Lainie Friedman Ross said. “People are going to think, ‘If my kid has this, I’m going to have to push real hard. If my kid doesn’t have it, I’m going to give up before I start.'” Better, she says, to just let children “follow their dreams.” (CBS News)