==Possible causes of autism==
Obvious potential causes of Although no one knows how autismdevelops, or vulnerability to itexperts have focused on physical causes such as environmental toxins, are the environment (including increased vaccinations), genetic predispositionvaccine preservative [[thimerosal]], and the diet of both the mother (pre-birth and during breastfeeding) and child. Some experts have speculated about [[genetic predisposition]].
=== Environmental Factors ===