Clues about the biological processes contributing to the development of Autism Spectrum Disorder (ASD) are uncovered in Nature Communications this week. The study investigates the contribution of information on the epigenome - markers on the genome that alter how genes are expressed, and that can be modified by environmental factors - to the understanding of disease development. By integrating genetic and epigenetic information from blood and brain biopsies, this study provides a framework of factors that influence the development of ASD.

To study the potential effects of genetic and epigenetic factors on ASD, Daniele Fallin, Christine Ladd-Acosta and colleagues combined data from human genetic studies in families with a child with ASD and integrated it with data from human epigenetic studies. By combining datasets of genetic and epigenetic data collected from different sources - cord blood, peripheral blood and brain samples - they identified epigenetic changes that associate with previously identified ASD genes. The gene locations of these epigenetic changes point to new biological hypotheses about how genes for ASD may disrupt development that were not apparent from genetic studies alone. Importantly, this study found significant overlap between the insights gained using peripheral blood epigenetic information and those from brain samples. This demonstration of the value of blood-based samples opens up possibilities to study epigenetic marks during the lifetime of individuals, whereas brain tissue can only be studied in post-mortem samples.