Kao, et al. (2010) found an association between certain cancers and autism.

Cancer is a disease not only of genetic mutations but also epimutations. Inactivation of tumor suppressor genes through hypermethylation is common in cancer. (Poulsen, et al, 2007) For example, Mulero-Navarro, & Esteller (2008) found epigenetic inactivation, through promoter hypermethylation, of the chromating remodeling factor CHD5 in breast cancer. Epimutagens are believed to play a role in tumorigenesis in some cases. (Phillips & Goodman, 2009; Pulling, et al, 2004)

Research indicates that epimutations may play a role in many cases of autism. Hypermethylation of the promoter regions of the MECP2 and oxytocin receptor genes, and their decreased expression, may be common in autism. (Nagarajan, et al, 2006; Gregory, et al, 2009)

Pollution may cause some epimutations. Pollutants linked to aberrant DNA methylation patterns include traffic-related pollution, tobacco smoke, cadmium, and methylene chloride. (Perera, et al, 2009; Breton, et al, 2009; Jiang, et al, 2008; Pulling, et al, 2004)

Could pollution increase the risk of autism through epigenetic mechanisms? Research on autism rates and pollution raises the possibility. (Windham, et al, 2006; Larsson, et al 2009) Among the pollutants that appear to be linked to higher autism rates are tobacco smoke, cadmium, and chlorinated solvents including methylene chloride. Much more research needs to be done.

Cancer is in part an epigenetic disease and epimutagens are believed to play a role in its epidemiology, so do epimutagens play a role in the epidemiology of autism, another condition where epigenetics is believed to be a factor?



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