A recent study published in Aging-US has found that age-related changes in sperm DNA may play a role in the risk of autism spectrum disorder (ASD) in children. The paper, titled "Age-specific DNA methylation alterations in sperm at imprint control regions may contribute to the risk of autism spectrum disorder in offspring," was led by Eugenia Casella and Jana Depovere, with Adelheid Soubry from the University of Leuven as corresponding author.
The research examined DNA methylation—a process that regulates gene activity without altering the genetic code—in sperm samples from 63 healthy, non-smoking men aged 18 to 35. Researchers measured methylation at hundreds of thousands of sites across the genome and identified more than 14,000 locations where levels changed with age. Most changes involved a gradual decrease in methylation as men grew older.
"To identify sperm-specific marks, we conducted an epigenome-wide association study in sperm from 63 men, using the Illumina 450K array," according to the authors.
While each change was small, many were located near imprint control regions—genomic areas that ensure certain genes are active only from one parent. These regions form during sperm development and typically remain after fertilization. Alterations here could impact how genes are regulated in children.
Several genes affected by these age-related changes have been previously associated with autism and are involved in brain development, nerve communication, and early growth. Disruptions in their regulation could increase susceptibility to neurodevelopmental differences.
The study provides new insight into previous evidence connecting paternal age with child health outcomes. However, the authors emphasize that autism is influenced by a combination of genetic and environmental factors; no single cause has been identified. The results suggest that biological changes in sperm related to aging might be one factor among many contributing to ASD risk.
By exploring how paternal age affects sperm biology, this research lays groundwork for further studies on reproductive health as trends shift toward later fatherhood.
