Why can't doctors figure out what causes autism?

I want to know too!: We all want to find out. There are many theories and researchers are looking to separate truth from fiction. Autism is a very complicated diagnosis, and my passion is helping coach children and families dealing with the diagnosis. As we learn more about genetics i feel we will have more answers in the future. Finding out how environment affects certain genes will also help the search.

There are many known: Causes: > 30 known syndromes, "copy repeat errors" in small bits of dna in certain genes, factors that change the function of certain fetal genes early in pregnancy, (e.g., toxins, viruses & ⬇ Folic Acid levels). Specific atypical white matter development is seen on brain mri's in infants long before they show clinical signs of asd. The ? Is, what triggers the expression of the altered genes.