Article

Epigenetics of autism

This short review summarises how epigenetic mechanisms are implicated in autism spectrum disorder (ASD). Research is ongoing and the field is complex; no single epigenetic explanation accounts for ASD.

Summary:

Epigenetic alterations (for example, differential DNA methylation and histone marks) have been observed in brain tissue and peripheral samples from people with ASD. These changes may affect the expression of genes involved in synaptic function, neuronal development and immune signalling.
Some genes linked to ASD encode chromatin modifiers or epigenetic regulators themselves; mutations in these genes can have widespread effects on gene expression.
Epigenetics provides a mechanism by which environmental factors (prenatal exposure to toxins, maternal stress, nutrition, parental age) can influence neurodevelopmental risk without changing the DNA sequence.
Sex differences: Epigenetic processes such as X‑inactivation, sex hormone effects on epigenetic enzymes, and imprinting can contribute to differing male/female prevalence and presentations.
Clinical implications are currently limited: epigenetic biomarkers are under investigation but not yet validated for diagnosis. Therapeutic modulation of epigenetic enzymes remains experimental and carries risks.