Parents often not told of problem until they have more children

ATLANTA - Katie Clapp knew something was wrong with her newborn boy, but it took two years and dozens of doctor visits before he was diagnosed with Fragile X Syndrome, the most common inherited cause of mental retardation. By that time, Clapp had given birth to another child carrying Fragile X. <br> <br> Clapp and others say they would have not had more children if they knew that they were passing on a genetic problem. <br> <br> A study released Thursday by the Centers for Disease Control and Prevention is the first look at the long diagnosis process for Fragile X and whether all newborns should be screened for it. The syndrome affects only 50,000 people nationwide and can&#39;t be cured, but many parents said they wish they&#39;d been told about it before having more children. <br> <br> In a survey of 140 families with a Fragile X child, 40 percent of the parents had given birth to additional children before they learned they were carrying the mutation, which occurs on the X chromosome and disrupts production of a protein that&#39;s important for the brain&#39;s reasoning skills. <br> <br> About one in four-thousand boys is born with Fragile X. Girls are many times more likely to carry the mutation, about one in 269, but not all display symptoms because females have two X chromosomes, not one as boys do.