Narrowing down gene and environment interactions in autism

With hundreds of genes, thousands of environmental factors, and now sex being variables in determining risk for autism, where should science start?  Over the decades researchers have been able to start narrowing down the combinations based on specific behaviors of interest, genes, and mechanisms which may narrow down which gene, which environmental factor and which sex.  Dr. Sara Schaafsma and Dr. Donald Pfaff from Rockefeller University combined the three, and found that epigenetic changes in an autism risk gene called contact in associated protein like 2 contributed to elevation of risk for autism behaviors following maternal infection.  In other words, being male and having the mutation produced small changes, increased by the environmental factor.  In another separate study, Dr. Keith Dunaway and Dr. Janine LaSalle at UC Davis used brain tissue to look at a rare variant for autism on chromosome 15.  Typically, mutations of this area of the genome are thought to cause autism.  However, the effects of these mutations are also increased when environmental factors are present, leading to more de novo mutations.  These are all examples of scientific breakthroughs that are helping better understand what causes autism.  Even when it looks like one thing, it’s multiple things.

Old exposures, new diagnoses and more efficient screening for toddlers

This week, two important studies came out on different topics in autism research.  In the first study, an exposure which has been around for decades, PCB’s, a toxic industrial chemical which has been banned from manufacture or use for the past few decades, was linked to autism.  This dispels the myth that only exposures that have been introduced since the observance in the rise in diagnoses are relevant for study.  First author Kristen Lyall gives her perspective. Here is a website on how to avoid PCBs even though they have been banned.

Second, screening for autism in pediatricians offices has always been challenging.  Patients get 10 minutes at most with their doctor, these doctors have to fit in an hours worth of assessments in this time.  So how can you get them to conduct a screening for autism and add in extra questions?  Kennedy Krieger Institute published on a way that seems to work without sacrificing quality.  Hear more about both on this week’s podcast.