Parental germline exposure hypothesis

Instead of attributing autism risk solely to fetal in‑womb exposures or inherited DNA, ask whether environmental toxicants or other insults cause mutations or epigenetic changes in parents' germ cells (sperm or eggs) that then raise autism risk in offspring. This reframes some 'environmental' causes as upstream effects on parental genomes rather than classic gestational exposures. — If substantiated, it would shift research priorities, regulation, and public messaging from pregnancy‑only interventions to preconception environmental policy and paternal health.