Sunday, March 25, 2012

New autism genetic brain growth study may refute some urban legends

I read with interest (albeit admittedly with limited understand)
the new article that demonstrates evidence for a genetic etiology for the abnormal brain growth and other anomalies in autism. Scientific American has published an overview of this work that's more understandable to the lay person (myself included) than the primary source, which I've also linked to above.

One finding that I think at least some labs have replicated is abnormal brain growth in autism. Eric Courchesne recently published a study demonstrating abnormal brain growth in the prefrontal cortex of postmortem autistic subjects and finding autistic brains have 67% more neurons in this area than normal controls. I've written about this elsewhere.

This study examined genetic pathways and defects in postmortem brains of both autistic children and adults as compared to age-matched controls.

One of the striking findings of this work was the fact that the genetic defects and how they affected the brain were qualitatively different in the adult group than in children.

The last sentence in the conclusion section of the article is particularly compelling: Further knowledge of the specific developmental neurobiological mechanisms behind the age-dependent anomalies reported here could point to distinct early developmental processes that lead to autism, uncover mechanisms that respond to early pathologies in the mature brain and suggest novel molecular targets for prevention strategies and treatment over the course of the disorder .

This study may have relevance to two well-known tenets in the autism community: 1. Early intervention makes a difference in the outcome of autistic children. The earlier the treatment is started the better the prognosis. 2. One of the main arguments of the neurodiversity movement that the term "prevention" is in reality a codeword for abortion and that genetic research in autism will only lead to widespread termination of pregnancies involving autistic fetuses. The ND movement gives the oft-cited statistic of a more than 90% abortion rate of Down's syndrome children as evidence for this. There are probably a number of problems with this argument, but that may be the subject of a future gadfly blog post.

Though the "early intervention" mantra is repeatedly chanted to parents of small autistic children by entrepeneurs financed by the IDEA law (ABA practitioners and others), to the best of my knowledge, no studies have been done linking age of intake to a more favorable prognosis or outcome.

As I've written before, I underwent psychoanalysis beginning the late 1950s. This was the intervention of choice in those days. I went from nonverbal feces smearing to mildly impaired autistic during this time period. Was it the psychoanalysis that helped me? Have ABA and other more contemporary interventions been responsible for at least partial recovery of those with autism? I believe the differences between the postmortem brains in the children versus adults as well as different genetic pathways may account for recovery in some cases. Some persons who had certain types of genetic defects as children, may not have had the as adults. Perhaps the adults without certain deficiencies did not have genes that interfered with patterns repairing neurons etc. Perhaps that accounts for recoveries rather than early intervention. Though admittedly it is speculation, I don't believe this hypothesis is farfetched.

ASAN and other neurodiversity organizations have repeatedly claimed that all research funded by Autism speaks, the Simons foundation, etc. has a goal of finding a way abort autistic fetuses. This includes fMRI studies and studies of TMS and mu wave suppression which do not appear to have any relevance to genetic research to a reasonable person. This paper may be the start of empirical evidence, that in fact, genetic research is our ace in the hole for preventing autism. No, not aborting the autistic fetus, but perhaps finding the genetic mechanisms prenatally that cause this brain overgrowth and possibly other problems the autistic may have. For this reason, I believe studies like this should be funded and it may have promising implications of being able to prevent the fetus from becoming autistic in the first place or even possibly helping those already born.

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