 The central aim of this project is to characterize the expression of microRNA miRNA in the saliva of children with autism spectrum disorder ASD. In 2012 the CDC reported that the prevalence of ASD in U.S. children was 1 in 88. Yet, the biological causes, diagnosis, and treatment of this disease remain ambiguous. Recent research suggests that certain factors that regulate gene expression may play a role in ASD. To investigate this possibility we plan to measure small molecules called miRNAs in the saliva of children with ASD. Studies on miRNAs have shown that they can be extruded from neurons as extracellular signaling molecules and this knowledge provides a new approach for examining the genetic regulation of the central nervous system. 