The whole autism genetic theory is a red herring. The truth is our DNA is massively effected by elements and substances in our environment and food. Since DNA can be altered, the idea that any disease is just simply genetic is a fallacy. DNA can be damaged throughout generations.
For example Copper...(What do you think happens in copper deficiency?)
Regulation of gene expression
Copper-dependent transcription factors regulate transcription of specific genes. Thus, cellular copper levels may affect the synthesis of proteins by enhancing or inhibiting the transcription of specific genes. Genes regulated by copper-dependent transcription factors include genes for copper/zinc superoxide dismutase (Cu/Zn SOD), catalase (another antioxidant enzyme), and proteins related to the cellular storage of copper (3).
http://lpi.oregonstate.edu/infocenter/minerals/copper/
Additionally, The toxicity of former generations means current generations are affected through epigenomic alteration.
"Drugs given to pregnant
animals can affect
the brains and behavior of at
least two generations of off-
spring, Toronto researchers say.
The finding adds to evidence
that dietary intake, drug use,
toxic exposure, and other en-
vironmental factors can cause
“epigenetic” effects—that is,
changes in gene function that
occur in the absence of
changes in DNA sequencing
and that can be inherited by
future generations. "
http://www.crimetimes.org/ct122.pdf
The concept that genetics are set in stone is a fallacy.
"Several environmental factors, including, pesticides, metals, head injuries, lifestyles and dietary habits have been associated with increased disease risk or even with protection. Hundreds of genetic variants have been investigated as possible risk factors for the sporadic forms, but results are often conflicting, not repeated or inconclusive. New approaches to environmental health research are revealing us that at the basis there could be chemically induced changes in gene regulation and emphasise the importance of understanding the susceptibility of the human epigenome to dietary and other environmental effects."
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2C-4TTHWJY-1&_use...
Try again. The genetic theory of autism is patently false with all the co-factors out there you can be assured those studies you insinuate of, missed something. For example did they take into account whether or not the test subjects parents had mercury
Amalgam fillings? They didn't even take that into account.