Gene X Environment Interactions in Autism Spectrum Disorders: Role of Epigenetic Mechanisms

• Main Authors: Sylvie eTordjman, eszter eSomogyi, Nathalie eCoulon, Solenn eKermarrec, David eCohen, Guillaume eBronsard, Catherine eWeismann-Arcache, Michel eBotbol, Bertrand eLauth, Marianne eBarburoth, Vincent eGuinchat, Pierre eRoubertoux, Viviane eKovess, Marie-Maude eGeoffray, Jean eXavier
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2014-08-01
• Series: Frontiers in Psychiatry
• Subjects: epigenetics; environment; multidisciplinary; gene x environment interactions; autistic spectrum disorders; multifactorial
• Online Access: http://journal.frontiersin.org/Journal/10.3389/fpsyt.2014.00053/full

Several studies support currently the hypothesis that autism etiology is based on a polygenic and epistatic model. However, despite advances in epidemiological, molecular and clinical genetics, the genetic risk factors remain difficult to identify, with the exception of a few chromosomal disorders and several single gene disorders associated with an increased risk for autism. Furthermore, several studies suggest a role of environmental factors in autism spectrum disorders (ASD). First, arguments for a genetic contribution to autism, based on updated family and twin studies, are examined. Second, a review of possible prenatal, perinatal and postnatal environmental risk factors for ASD are presented. Then, the hypotheses are discussed concerning the underlying mechanisms related to a role of environmental factors in the development of ASD in association with genetic factors. In particular, epigenetics as a candidate biological mechanism for gene X environment interactions is considered and the possible role of epigenetic mechanisms reported in genetic disorders associated with ASD is discussed. Furthermore, the example of in utero exposure to valproate provides a good illustration of epigenetic mechanisms involved in ASD and innovative therapeutic strategies. Epigenetic remodeling by environmental factors opens new perspectives for a better understanding, prevention and early therapeutic intervention of ASD.