For the majority of patients diagnosed with autism, no straightforward genetic cause has been identified. One of the important theories about autism implies that in some brain regions, such as the prefrontal cortex, a number of genes are not switched on properly during normal development, as they are in healthy subjects. However, until now the molecular techniques to study these phenomena have been lacking. This research is based on extremely innovative techniques that were recently developed in the researchers' laboratories. They were able, for the first time, to selectively isolate chromosomal materials and chromatin from the nerve cells of the human brain obtained postmortem, and study "epigenetic markings" (basically, chemical modifications that regulate gene expression and function without altering the genetic code) on a genome-wide level. The aim is to examine epigenetic gene activation patterns during normal prefrontal cortex development and search for potential alterations in autism and to better understand the disease on a molecular level. This research should clarify whether epigenetic markings are dynamically regulated in human neuronal chromatin, and if major psychiatric diseases such as autism are associated with changes in the neuronal epigenome. If successful, the study could provide a framework for future early intervention studies specifically designed to at risk subjects, especially those cases where chromatin alterations could play a role in the disease process.