Causes of Autism
Scientists aren't certain about the causes of autism, but recent studies strongly suggest that some people have a genetic predisposition to the disorder. Other studies suggest that abnormal levels of neurotransmitters in the brain may be among the causes of autism, but these are preliminary findings and require further study.
Causes of Autism: An IntroductionAutism research scientists aren't certain of the causes of autism, but it's likely that both genetics and environment play a role.
Family Factors as Causes of AutismRecent studies strongly suggest that some people have a genetic predisposition to autism. In families with one autistic child, the risk of having a second child with the disorder is approximately 5 percent, or one in 20. This is greater than the risk for the general population.
Autism researchers are looking for clues about which genes contribute to increased susceptibility. In some cases, parents and other relatives of an autistic child show mild impairments in social and communicative skills or engage in repetitive behaviors. Evidence also suggests that some emotional disorders -- such as manic depression -- occur more frequently than average in the families of people with autism.
The theory that parental practices are among the possible causes of autism has now been disproved.
Neurotransmitters as Causes of AutismSome autism research studies suggest that autistics have abnormal levels of serotonin or other neurotransmitters in the brain. These abnormalities suggest that autism could result from the disruption of normal brain development early in fetal development caused by defects in genes that control brain growth and that regulate how neurons communicate with each other. While these findings are intriguing, they are preliminary and require further study.
Causes of Autism: SummaryWhile there are no known causes of autism, research on possible genetic, infectious, immunological, and environmental causes and mechanisms of autism is under way.