The Genetic Component of Autism

There's a lot of different theories. We know that through twin studies and stuff like that, that there's a large genetic component to autism. But the bulk of it is clearly genetic. And they've done studies on this that showed that a sizable reason for the increase has been this diagnostic substitution or broadening of the criteria. There's every year or two, there's some new study that says, oh, well, maybe in utero, exposure to something can cause autism. A lot of times those studies are pretty weak.