Epigenetic responses and the developmental origins of health and disease

Maternal and paternal factors influence offspring development and program its genome for successful postnatal life. Based on the stressors during gestation, the pregnant female prepares the fetus for the outside environment. This preparation is achieved by changing the epigenome of the fetus and is referred to as 'developmental programming'. For instance, nutritional insufficiency in utero will lead to programming events that prepare the fetus to cope up with nutrient scarcity following birth; however, offspring may not face nutrient scarcity following birth. This d iscrepancy between predicted and exposed postnatal environments are perceived as ' stress' by the offspring and may result in cardiovascular and metabolic disorders. Thus, this developmental programming may be both beneficial as well as harmful depending on the prenatal vs postnatal environment. Over the past three decades, accumulating evidence supports the hypothesis of Developmental Origin of Health and Disease (DOHaD) by the programming of the fetal phenotype without altering the genotype per se. These heritable modifications in gene expression occur through DNA met hylation, histone modification and noncoding RNA-associated gene activation or sil encing, and all are defined as epigenetic modifications. In the present review, we wi ll summarize the evidence supporting epigenetic regulation as a significant compo nent in DOHaD.