In spite of many decades of study, the causes of autism remain poorly understood, and each new study seems to bring more complexity to the picture of the disease’s biology.  Recent genetic analyses, however, have revealed an intriguing clue: some autistic patients carry a mutation in the patched domain-containing (PTCHD1) gene.  Here, MIT researchers try to understand PTCHD1’s normal function in order to better understand its role in the disease.  Their preliminary results suggest PTCHD1 may be expressed in glial cells (shown here), which provide support and protection for neurons in the brain.