Oberlander et al., 2008; Weaver et al., 2004; Weaver et al., 2001). While previous studies have controlled for maternal cigarette smoking during pregnancy and did not find significant associations between maternal cigarette smoking during pregnancy and aberrant methylation at the 13 CpG sites in exon 1F of the GR gene (Filiberto, et al., 2011), a more comprehensive analysis of the promoter region controlling expression of GR may reveal CpG loci more responsive to and influenced by maternal cigarette smoking during pregnancy. Future work might be conducted using animal models and human cohorts and should utilize a variety of tissues for analysis, including but not limited to placenta, specific brain regions, saliva, and blood. A more comprehensive investigation of altered DNA methylation of the GR gene promoter associated with maternal cigarette smoking during pregnancy might better describe effects of environmental toxicant exposure during pregnancy on mediators of the hypothalamic-pituitary-adrenal (HPA) axis, which may contribute, in part, to an increased risk for developing psychological disorders in childhood or later in life. Investigation of the epigenetic mechanisms which may underlie a suite of psychological disorders, including but not limited to post-traumatic stress disorder (PTSD), depression, schizophrenia, and ADHD, may provide researchers with a
