Study: Half of intellectual disability caused by random, not inherited, genetic mutations

(Source: CBS News)

More than half of the cases of severe intellectual disability caused by genetic defects are the results of random mutations, not inherited mutations passed down from parents, a new study suggests. The findings of the small-scale European study give hope to parents of children born with  severe intellectual disabilities who are worried about having another baby with the same condition, said Anita Rauch, chair of the Institute of Medical Genetics in Zurich who was one of the Study's lead authors.