Autism is a general term for quite a wide range of disorders called the Autistic Spectrum. My 14 year old has Aspergers Syndrome which is on the Autism Spectrum and his is at quite a low level compared to many I have met.

With Aspergers in particular much evidence exists that there could be an environmental influence in the development of the disorder. With Blair he developed normally until he was 18 months old ... and had his MMR immunisation.

I have since read quite a bit about the link between MMR and Aspergers and as a result my youngest did not get this immunisation until he was 11.