Early Life Environment, DNA Methylation and Behavior
from: Epigenetics: A Reference Manual (Edited by: Jeffrey M. Craig and Nicholas C. Wong). Caister Academic Press, U.K. (2011)
The DNA molecule contains within its chemical structure two layers of information. The DNA sequence that bears the ancestral genetic information and the pattern of distribution of covalently bound methyl groups to cytosines in DNA. While the genetic information is similar in all tissues in the individual, the pattern of distribution of methylation across the genome is cell-type specific. DNA methylation is an important regulator of gene function. Recent data that will be discussed here that supports the hypothesis that DNA methylation is a reversible biological signal. This expands the potential role of DNA methylation beyond embryogenesis to other time-points in life and to post mitotic tissues such as the brain. DNA methylation is proposed to act as a genomic response to both physical and social signals from the environment at different time points in life and to serve as a genomic memory of these exposures at different time scales, stably altering gene expression programming and thus modulating the physical and behavioral phenotypes to respond to these environments. It is hypothesized that DNA methylation provides within the structure of the DNA a dynamic interface between the changing world around us and the relatively fixed and stable genome read more ...