Autism is called idiopathic which means the cause of autism is unknown. As there are different levels of severity and combinations of symptoms in autism, there are probably multiple causes.
The best scientific evidence available today points toward a potential for various combinations of factors causing autism – multiple genetic components that may cause autism on their own or possibly when combined with exposure to as yet undetermined environmental factors. Timing of exposure during the child's development (before, during or after birth) may also play a role in the development or final presentation of the disorder.
A small number of cases can be linked to genetic disorders such as Fragile X, Tuberous Sclerosis, and Angelman's Syndrome, as well as exposure to environmental agents such as infectious ones (maternal rubella or cytomegalovirus) or chemical ones (thalidomide or valproate) during pregnancy.
There is a growing interest among researchers about the role of the functions and regulation of the immune system in autism – both within the body and the brain. Piecemeal evidence over the past 30 years suggests that autism may involve inflammation in the central nervous system. There is also emerging evidence from animal studies that illustrates how the immune system can influence behaviors related to autism. Autism Speaks is working to extend awareness and investigation of potential immunological issues to researchers outside the field of autism as well as those within the autism research community.
While the definitive cause (or causes) of autism is not yet clear, it is clear that it is not caused by bad parenting. Dr. Leo Kanner, the psychiatrist who first described autism as a unique condition in 1943, believed that it was caused by cold, unloving mothers. Bruno Bettelheim, a renowned professor of child development perpetuated this misinterpretation of autism. Their promotion of the idea that unloving mothers caused their children's autism created a generation of parents who carried the tremendous burden of guilt for their children's disability.
Reference: The Autism Speaks website. [Online]. Available: http://www.autismspeaks.org/what-autism
Dept. of SWE, FSIT
Daffodil International University