We do not know much about the causes of autism. We do know that there is a strong genetic basis for autism. Often, there is more than one autistic person in a family. The genetics of autism are very complicated. There is no single autism gene. Instead there are a number of different genes which have been associated with autism. These genes work in different combinations in different people. Furthermore, research suggests that there are also unknown environmental factors which contribute to autism. What these environmental factors are is not clear, and it is likely that the genes and environment combinations which lead to autism will be different in different families.

There are a few things that we know do not cause autism:

  • Bad parenting: when autism was first identified, one of the ideas was that autism may be caused by cold and distant mothers (a theory called the “refrigerator mother hypothesis”). This theory was thoroughly disproven in the 1970s when the first studies showed that autism had a strong genetic component.
  • The MMR jab: in the late 90s and early 2000s, Andrew Wakefield made claims through press conferences and research studies that there may be a link between autism and the MMR jab. These claims were found to be false, the original journal article was retracted and Andrew Wakefield was struck off the UK medical register. A large number of studies from around the world have shown no association between autism and the MMR shot. Despite the evidence that there is no link, there was for many years substantial media coverage of Wakefield’s position which caused a reduction in the uptake of the MMR jab. This in turn has caused an increase in the incidence of very dangerous diseases like measles.