MCA/MR have over 2000 known causes and are currently incurable. It appears based on known genetic, chromosomal, and epigenetic factors, that there are multiple eitiologies for the behavioral/cogntiive syndrome/spectrum we term ASDs/PDDs. It is an extremely complex neurological puzzle that our immediate gratification society insists immediate, concrete answers for, answers that will eventually come, but will take time.
As almost no MCA/MR are curable in the sense that you would seem to be using, and since it appears that the ASDs are related to MCA/MR, my answer is that autism would also appear to be incurable. Not untreatable, though, for many. However, the underlying neurological differences/ the underlying chromosomal and genetic differences/ and probably the epigenetic causes will all stand in the way of a "cure."
I recognize that was probably too many sentences for you, but what can a gal do?
*** Should also be noted that while I would make my children's lives easier, smoother, and while I will work tirelessly to give them the tools they need to survive and thrive while working at making the world they live in more compassionate and accepting, I would not for anything cure them of autism. The way their brains work is nothing short of amaizing. I would however undo the stroke damage my son suffered in a heart beat. Now that will make the vaccine-damaged parents pissy, so let me explain that I don't buy into your heavy metal toxicity view or vaccine damages view. My children never reacted adversely to a vaccine and they were always different from neurotypical; there was never regression. They do not have comorbid conditions that the vaccine-damage parents present with (not denying that there is a proportion of children with autism who have comorbid conditions, I'm noting mine DON'T).