Two different groups of genetic mutations may contribute to autism spectrum disorders for high-IQ boys and low-IQ boys and all girls with autism, finds a new study in the journal Nature.
Researchers analyzed the genes of 2,500 families in which one child has an autism spectrum disorder. At least 30 percent of autism disorders are caused by so-called “de novo” mutations, which occur spontaneously rather than being passed down from a parent.
Within the children with the most severe cases, including boys with low IQs and girls, the researchers found those sorts of spontaneous mutations in 27 new genes, making it likely that problems in these genes contribute to severe autism.
