Abstract

The goal of genome-wide association studies is to identify SNPs unique to disease. It usually involves a single sampling from subjects' lifetimes. While primary DNA sequence variation influences gene-expression levels, expression is also influenced by epigenetics, including the 'somatic epitype' ), an epigenotype acquired postnatally. While genes are inherited, and novel polymorphisms do not routinely appear, G is fluid. Furthermore, G could respond to environmental factors and to differences in exercise, maternal care and dietary supplements - all of which postnatally modify oxidation or methylation of DNA, leading to altered gene expression. Change in epigenetic status may be critical for the development of many diseases. We propose a 'longitudinal epigenome-wide association study', wherein G are measured at multiple time points along with subjects' histories. This Longitudinal epigenome-wide association study, based on the 'dynamic' somatic epitype over the 'static' genotype, merits further investigation