Early-Life Exposure to the Chinese Famine Is Associated with Higher Methylation Level in the INSR Gene in Later Adulthood.

We examined the association between the China famine exposure in early life and DNA methylation of INSR (hg18, chr19:7110130-7110574) and CPT1A (hg18, chr11: 68286513-68286952) related to growth and metabolism in 235 subjects selected from two provinces in China. The subjects were categorized into prenatal famine-exposed group and non-exposed group based on their birthdates. DNA methylation at the INSR gene locus was assayed from peripheral white blood cells using the Sequenom's MassARRAY system. Two dependent samples t-test was used to compare the difference between the exposed group and non-exposed group. DNA methylation level of INSR was higher among individuals who exposed to the China famine in the fetus than that of non-exposed group (d = 3.3%, P = 0.006). A significant interaction between famine exposure and province was observed for INSR (P < 0.001). DNA methylation level of INSR was positively associated with triglyceride (β = 0.011, P = 0.021), and negatively associated with high-density lipoprotein cholesterol (β = -0.039, P = 0.021). Moreover, exposed group had higher meat consumption than non-exposed group in severe exposure area. Prenatal exposure to the China famine plus later life eating habits might regulate epigenome.