Interesting Research Result on Autism

The NeuroLogica blog has an interesting post on ASD (Autism Spectrum Disorder). Here is the bit I found most interesting because it cites an interesting phenomenon of copy number variation which can act to turn up or down sociability:

Sanders et al studied 1124 families with one affected child with ASD and one unaffected child, with unaffected parents. They found that 6-8% of them could be explained by changes in copy number variants – how many copies of specific genes were present. Most intriguing, they found:

We find significant association of ASD with de novo duplications of 7q11.23, where the reciprocal deletion causes Williams-Beuren syndrome, characterized by a highly social personality.

In other words – at one gene location where a deletion causes a syndrome characterized by a highly social personality, they found duplications associated with a decrease in sociability. This strongly suggests that the gene in question has a strong influence on sociability, and can be either turned up or down depending on the genetic change.

And this:

In another study in the same issue researchers find that large networks of genes are responsible for the ASD phenotype. Further they provide evidence that could explain the fact that males are at higher risk of ASD than females. They find that a much greater perterbation in the gene network is required for ASD to manifest in girls than in boys.

And it interesting that they are eliminating epigenetics as an explanation:

Genes evolve to respond to the environment, and increasingly scientists are identifying important epigenetic factors in disease. But the research to date suggests a highly dominant role for genetics in autism, and this recent research adds to the growing body of research supporting this.

Go read the original article to get the embedded links.