Autism researchers already knew that a variant of gene called CNTNAP2 that appears in about one-third of people is associated with higher risk for developing the condition. A study this week out in Science Translational Medicine puts that genetic marker together with what it appears to do in the brain: cause too many connections inside the frontal lobe of the brain, but too few from there to other brain regions. That could be a key clue in unraveling the learning and language difficulties that frequently appear in autism spectrum disorders.
The gene produces a protein called CASPR1 and is active during brain development — mostly during frontal-lobe development. “During early development, it is localized to parts of brain that are ‘more evolved’ — areas where learning and language happen, the frontal lobes where really complex thinking takes place,” says Ashlee Scott-van Zeeland, a postdoctoral fellow at the Scripps Translational Science Institute in La Jolla, Calif., and lead author of the study. “[It is] thought to help structure the brain.” [TIME]
To study its effects, Scott-Van Zeeland and company studied 32 kids between 11 and 13 in age. Some were autistic, some not, and many of the non-autistic kids carried the CNTNAP2 gene variant. The scientists examined the children’s brains through fMRI while the kids played a game intended to stimulate brain regions that the gene affects.