Epigenetics is the study of gene regulation and organization that occurs independent of changes in a gene’s “code,” or DNA sequence. Indeed, the vast majority of genes in a given cell remain off, or inactive, at a given time. As in other parts of the body, normal brain development and function depend on the right genetic “switches” being flipped on or off at the right time. Histone methylation is one such epigenetic switch. Autism scientists have speculated that increased risk of autism might result from problems in the control of gene expression in brain cells. Like DNA mutations, these epigenetic changes can be inherited and run in families. But they can also be caused by exposure to chemicals, lack of crucial nutrients and other many possible stresses This project will explore disease-associated roles of histone methylation. Because more than 98.5% of human genomic DNA does not encode protein sequence, the epigenetic fine mapping of brain cell genomes, including histone methylation, will be important in order to understand the potential role of the these vast portions of non-coding DNA for the neurobiology of autism.