Dietary supplementation with polyunsaturated fatty acid during pregnancy modulates DNA methylation at IGF2/H19 imprinted genes and growth of infants (1120.3)

Abstract

Epigenetic regulations of imprinted genes are highly plausible explanation for the associations of dietary exposures in early life and the onset of diseases in adulthood. We tested whether prenatal dietary supplementation with docosahexaenoic acid (DHA) during pregnancy may modulate epigenetic states at birth in a randomized intervention trial among Mexican pregnant women supplemented daily with 400 mg of DHA or a placebo from 18 to 22 week of gestation to parturition. We applied quantitative profiling of DNA methylation states at IGF2 promoter 3 (IGF2 P3), IGF2 DMR and H19 DMR in cord blood mononuclear cells of the DHA‐supplemented group (n=131) and the control group (n=130).There were no significant differences between the DHA and the control groups for DNA methylation levels at imprinted genes; however in stratified analyses, we observed a positive association between DNA methylation levels and maternal BMI; IGF2 DMR methylation was higher in the DHA than the control groups in infants from overweight mother (p=0.03) and H19 DMR, methylation levels were significantly lower in the DHA than control groups in infants from normal weight mothers (p=0.01). Prenatal DHA supplementation modulated IGF2/H19 methylation in infants and methylation levels at IGF2/H19 imprinted regions were related with maternal BMI. Epigenetic mechanism may be modulated by DHA with potential impacts on growth and development of children.Grant Funding Source: NIH‐NICHHD (RO1HD058818), NIH (RO1HDO43099) and CONACYT Mexico (SALUD‐2008‐01‐87121)