Since the first pair of autism was studied and discovered in 1977, several teams have compared the prevalence of autism in the pair and shown that autism is highly inherited. When the same pair has autism, there is an 80% chance that other pairs will be the same. But genetics alone is not the only reason for autism in children. Environmental factors also play a role in this situation. But scientists do not agree with the relationship between environment and genes. Some environmental influences, such as birth defects, may be synchronized with genetic factors to cause or exacerbate autism.

Is there such a thing as an autism gene?
Not really. There are many disorders associated with autism that stem from a mutation in a gene. Including fragile X chromosomes or rat syndrome. But less than one percent of non-syndromic autism cases are rooted in a gene mutation. There has never been such a thing as an autism gene. This means that no gene is definitely mutated in the body of any person with autism spectrum disorder. The list of genes involved in autism is still being studied. Scientists have measured about 100 genes that have been linked to autism. Most of these genes are important in connecting neurons or controlling the state of other genes.