“…Similar to the human Dutch Hunger Winter famine case during World War II, environmental exposure to factors including nutritional, psychological, and social stress, toxins and substance abuse in early life may serve as triggers for epigenetic programming for various comorbidities later (Vaiserman, 2015a;Vaiserman, 2015b). In mammals, the epigenome may be subject to major epigenetic modifications during gametogenesis and early embryogenesis (Messerschmidt et al, 2014;Vaiserman, 2015a;Vaiserman, 2015b). In the early embryo, methylation levels are minimal to allow removal of gamete-specific methylation inherited from parents for the purpose of pluripotency.…”