Genes jump more in one type of autism

Increased activity observed in brains of girls with Rett syndrome

Gene defects that lead to Rett syndrome, a severe form of autism that predominantly strikes girls, also get jumping genes hopping in neurons, a study in the November 18 Nature shows. If the jumping genes land in parts of the genetic blueprint that are important for brain development or function, they could contribute to the variability of symptoms seen in the disorder.