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 does not have a single known cause. Given the complexity of the disorder and the fact that symptoms and severity vary, there are likely many causes.Both genetics and the environment can play a role in the development of autism spectrum disorder (ASD).There is no single cause of ASD, but many different factors have been identified that may make a child more likely to have ASD, including environmental, biological, and genetic factors. Scientists believe that both genetics and the environment are likely to play a role in ASD.There is great concern that autism rates have increased in recent decades without a full explanation as to why. Researchers have identified several genes associated with the disorder, and imaging studies of people with ASD have found differences in the development of several regions of the brain. 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. Autism is more common in children who are born prematurely, and environmental factors may also play a role in gene function and development, but specific environmental causes have not yet been identified. The theory that parental practices are responsible for ASD has long been refuted. Multiple studies have shown that vaccination to prevent childhood infectious diseases does not increase the risk of autism in the population.In a minority of cases, there are very clear genetic abnormalities that cause autism.
In other cases, genetic differences are more complex and have not yet been discovered. This theory hypothesizes that an early developmental failure involving the amygdala cascades into the development of cortical areas that mediate social perception in the visual domain. A large body of evidence supports the idea that genes are a major cause of ASD or a major contributing factor. The exact genetic abnormalities that can lead to the remaining cases of autism are not entirely clear.As children with ASD become adolescents and young adults, they may have difficulty developing and maintaining friendships, communicating with peers and adults, or understanding what behaviors are expected at school or at work.
It is important to note that there is no single cause for autism; rather, it is likely caused by a combination of genetic and environmental factors.
