We know that there is no single cause for autism. Research suggests that autism develops from a combination of genetic and non-genetic or environmental influences.
Autism spectrum disorder
(ASD) is a developmental disability caused by differences in the brain, and it is likely that both genetics and the environment play a role in its development. Some people with ASD have a known difference, such as a genetic condition, while other causes are not yet known.Scientists believe that there are multiple causes of ASD that work together to change the most common ways in which people develop. We still have a lot to learn about these causes and how they affect people with ASD. Imaging studies of people with ASD have found differences in the development of several regions of the brain, and studies suggest that ASD could be the result of alterations in normal brain growth very early in development. These alterations can result from defects in genes that control brain development and regulate the way brain cells communicate with each other.
Environmental factors may also play a role in gene function and development, but specific environmental causes have not yet been identified. Autism is more common in children who are born prematurely, and multiple studies have shown that vaccination to prevent childhood infectious diseases does not increase the risk of autism in the population. Specific genetic causes can only be identified in 10% to 20% of cases, including specific genetic syndromes associated with ASD and rare changes in the genetic code.In conclusion, there is no clear cause of ASD, but research suggests that it develops from a combination of genetic and environmental influences. We still have much to learn about these causes and how they affect people with ASD.