alcohol effect are reported here. First, alcohol prevented programmed diversification of DNA methylation during differentiation, i.e. it prevented moderately methylated genes from increased or decreased methylation, or further, becoming significantly hyper- or hypo-methylated. As promoter DNA methylation represses transcription and recruits other repressive chromatin-modifying activities to the chromatin (Bird, 2002), the prevention of programmed hyper- and hypo-methylation of a set number of genes can disrupt chromatin remodeling, and, thus, differentiation reprogramming of quiescent NSCs might be incomplete. The second effect of alcohol is the methylation change of the genes that were not supposed to alter in the normal program at this stage of normal differentiation. The untimely methylation change of these genes also have an opportunity to affect the gene transcription and deviate differentiation.
