Epigenetic modifications, A possible mechanism for autism spectrum disorders (ASD) after assisted reproductive technology (ART).

Abstract

During brain development specific sensitive periods exist during which the brain is extremely sensitive to the influence of environmental factors that may result in developmental changes in the brain. These environmental factors can change gene expression through epigenetic modification. Epigenetic modification includes DNA methylation, chromatin remodeling, histone variants, histone substitute deposition, and histone modifications. Actions required for assisted reproductive technologies (ART) may act as environmental factors leading to epigenetic modification errors. In this thesis ART includes any kind of artificial treatment that promotes conception. The epigenetic modification errors may result in neurodevelopmental disorders, such as autism spectrum disorders (ASDs). ASDs include autism disorders (AD), Asperger syndrome (AS), and PDD-NOS. In this thesis a possible association between ART and ASDs due to epigenetic modification errors is examined. The literature is inconsistent and no definite association is found between ART and ASDs. However, the etiology of ASDs is not understood. Therefore, further research should be done on the etiology of ASDs, but also on the effect of the actions required for ART treatment, on the effect of reduced fertility or infertility on genetics and epigenetics of germ cells, and on epigenetic modification. This additional knowledge may provide a better insight in the possible association between ART and ASDs, through epigenetic modification.