Regular readers might recall me blogging about neural proteins awhile ago. If I may quote myself:
…when the authors blocked APC function, they found that levels of the proteins neuroligin and neurexin dropped. So what…? Well, without these two proteins at normal levels, synapses grew improperly. So what…? Turns out that scientists already know that mutuations in the genes for neuroligin and neurexin are associated with autism…
And now along comes a new study that builds on this science.
Palmer Taylor, associate vice-chancellor for Health Sciences at UC San Diego and dean of the Skaggs School of Pharmacy and Pharmaceutical Sciences, and colleagues report that misfolding of a protein called neuroligin-3, due to gene mutations, results in trafficking deficiencies that may lead to abnormal communications between neurons.
So here we have a situation where genetic mutations leads to a misfolding of a protein that results in affecting the growth of synapses which in turn affects the development of autism.
Taylor said identifying and describing the misfolded protein link advances understanding of the complex causes of certain autisms, including the influences of genes versus environment…
Thats an interesting statement. I will try to get in touch with Taylor to explain that further.
Left Brain Right Brain 
The problem with the concept of neurologin-3 ‘causing’ autism is that the association of neurolgin-3 mutations is associated not necessarly with autism per se but rather with mental retardation with or without a co-occuring ASD diagnosis. A study that examined high functioning people diagnosed with Asperger Syndrome or atypical autism unconfounded by the co-occurence of mental retardation found no evidence of the neurologin-3 family of genes associated in any way with autism.
http://www.ncbi.nlm.nih.gov/pubmed/18189281?
This particular study points out the ambiguity in autism definition and the problem of diagnostic substitution where it has turned out be virtually impossible to distuingish mental retardation from accuratly diagnosed autism.
Other studies point out that mutations in the family of neurologins have been identified in only a handful of cases and most of those with co-occuring mental retardation.
http://www.ncbi.nlm.nih.gov/pubmed/16077734
http://www.ncbi.nlm.nih.gov/pubmed/15274046
http://www.ncbi.nlm.nih.gov/pubmed/16508939