Paternal age and alterations in sperm DNA methylation are among the factors thought to contribute to the development of autism in offspring. An epigenome-wide association study was undertaken to determine whether alterations in a father's specific sperm DNA methylation correlate with autism susceptibility among offspring.

Sperm samples were obtained from 36 fathers of children who did or did not have autism. The samples were then tested for alterations in DNA methylation. There were no significant differences between the groups in terms of demographics, clinical characteristics, and father's age at the time of collection or conception. A genome-wide analysis was used to identify differential DNA methylated regions (DMRs). The researchers identified 805 DMRs.

The researchers report that genes associated with DMRs were found to correlate with previously identified autism spectrum disorder and neurodevelopment-related genes. The potential sperm DMR biomarker was validated-with approximately 90% accuracy-using blinded test sets of samples.

The study was limited by the small number of samples analyzed. The authors say additional studies that include more participants and greater ethnic diversity are needed.