I don't know if classical autism is rare, but it is what my son was diagnosed with. He had normal development until about 9 months. We have had genetic testing done and his autism is not genetically found. It has left us with the million dollar question... where the heck did this come from if it isn't genetic?

Nutritional support could help with genetic issues that are related to the various metabolic pathways. For example, if the child has difficulty with the methylization pathway due to some genetic factor, giving methyl B12, DMG/TMG, SAMe, etc. could help make up for it. I studied biological psychology back in college (never dreaming it would come in handy like this, LOL!) and there is a whole field called epigenetics that studies gene-environment interactions.

"Of course these are not the only pieces of evidence, and scientists continue to test, and re-test the safety of vaccines. A recently published exhaustive review examining 12,000 research articles covering 8 different vaccines concluded there was no link between vaccines and autism. While scientists still don’t know the exact causes of autism, we are looking like mad and one thing we can be extremely confident of is that it’s not vaccines."

http://www.mamamia.com.au/news/anti-vaccination...

What's even more confusing is that a child could be considered HFA but moderately impaired. The HF part because of an underlying above-average IQ but still have enough symptoms at the time of diagnosis to be considered moderate autism rather than PDD or Asperger's. My DD never experienced any regression and in hindsight we can recognize the symptoms started *VERY* early on, even if at the time autism wasn't on our radar. She has some red flags for mito disorder but our neurologist recommended against testing because it would be very expensive but there aren't any treatments at the moment beyond the nutritional support we are already doing.

Thanks so much to both of you for your input. Even though autism didn't whack me in the face until my son was 3, when it did, I was able to look back and realize that my son's autism actually began at birth. He was never vaccinated, so it's probably genetic, Classic Autism, right? Except that he responds so well to vitamin supplements and methyl B12, and you can't fix genetic problems with vitamins... or can you? So maybe it was exposure to toxins in utero. Except that I was so, so careful. I'm just having the time of my life finding the "autism model" that fits my son so that I can tailor therapies for him. We can't afford to try a lot of stuff, like HBOT, without some kind of indication that it might help him. We've got tests coming back this month that will hopefully provide more insight, but in the meantime I am wondering why classic autism seems so rare, and if any parents of these children have ever benefited from the biomedical treatments that seem to benefit regressive autism.