Do Genetics Play ANY Role in Causing Autism?

"Autism is linked to different genes in different people, 
and multiple genes could be involved in each affected person."
Genetic Engineering & Biotechnology News, November 1, 2011

Do genetics play ANY role in causing autism?

The view that autism is caused purely by genetics held sway for many years especially with respect to funding autism research. The "it's gotta be genetic" mindset has seen research dollars dedicated overwhelmingly towards genetic based autism research.  Research into possible environmental causes or contributors to autism has been minuscule by comparison. What have those genetic autism research dollars produced? I am a humble, irrational, distraught parent of a son with severe autistic disorder but as I read commentaries by people who know much more than I do about these subjects what I see is doubt about the role of genetics in causing autism.

Genomic Studies Are Adding to Evidence of Autism’s Highly Complex Nature, an article by Patricia F. Dimon, Ph.D.,  published November 1, 2011 on the Genetic Engineering & Biotechnology web site makes the argument that current research, like that arising from the AGRE (autism genetic resource exchange), is providing some idea of where some common underlying genetic factors involved with autism might be found but in making that argument also makes statements suggesting a limited role for genetics in causing autism disorders:

"From a biological perspective, autism presents a “profoundly complicated” array of disorders with significant genetic components and genomic alterations thought to “organize around a central theme of neural network infirmities and neuroimmunodysregulations,” according to Daniel J. Guerra, writing in the March issue of Autism Research and Treatment.

Autism is linked to different genes in different people, and multiple genes could be involved in each affected person. These genetic factors, in turn, may interact with as yet unidentified environmental factors. It is now known that new mutations show up in children whose parents do not carry the mutation. Additionally, it turns out that in cases where underlying genetic mutations have been identified, the gene abnormalities don’t necessarily predict the disorder.

“Do we really know that every time you make that mutation or you delete one copy of that gene, you cause autism?” asked John Constantino, M.D., a pediatric psychiatrist at Washington University in St. Louis, in an interview with Los Angeles Times. “We have no idea.”" (Underlining added - HLD)

How can we continue to play the "it's gotta be genetic" card of autism research, and ignore possible environmental causes or contributing factors, when genetic autism research has failed to provide any tangible results?  

After so many years of siphoning off autism research dollars has genetic research helped us understand how autism is caused or developed?

Do genetics really play any role in causing autism?

Apparently .... we have no idea.