Study Finds Aberrant Epigenome in Autism Dad Sperm; Imprinted Genes Implicated

SNORD115 regions were represented in 4 of the top 10 DMRs.Dani Fallin and Andrew Feinberg of John Hopkins University Center for Epigenetics, and colleagues, have found a DNA methylation pattern in the sperm of fathers with an increased risk of fathering autistic children that is also present in brains of unrelated autistic children. See the paper at the International Journal of Epidemiology, April 2015.

Looking at the sperm of fathers of young children considered at risk for autism, the team found 193 significant differentially methylated regions (DMRs), compared to controls; those sperm DMRs are large stretches of dozens of CpGs, not single CpG sites, and were consistent with 75 CpG probes from the 450K; and the DMRs are involved in developmental processes including imprinting disorders

The aberrant methylation was associated with genomic areas involved in the  imprinting disorders Angelman syndrome and Prader-Wili Syndrome. The region regulates neuron growth and produces important regulatory molecules. The large-scale methylation differences suggests epigenetic deviations in the germline may manifest as abnormalities in early brain development of offspring, producing the autism phenotype.