Germ-line epigenetic modification of the murine <i> A ^vy </i> allele by nutritional supplementation

TLDR

Epigenetic modifications mediate environmental effects on phenotype, and the murine A vy allele’s highly variable epigenetic state can be shifted by in‑utero methyl‑donor supplementation. The study investigates whether methyl‑donor supplementation alters the germ‑line epigenetic state of the A vy allele. Methyl‑donor supplementation during midgestation changes the epigenetic state of the paternally inherited A vy allele, shifting phenotypes in both exposed fetuses and their offspring, and demonstrating that maternal diet can produce heritable epigenetic changes that persist through germ‑line resetting.

Abstract

Environmental effects on phenotype can be mediated by epigenetic modifications. The epigenetic state of the murine A vy allele is highly variable, and determines phenotypic effects that vary in a mosaic spectrum that can be shifted by in utero exposure to methyl donor supplementation. We have asked if methyl donor supplementation affects the germ-line epigenetic state of the A vy allele. We find that the somatic epigenetic state of A vy is affected by in utero methyl donor supplementation only when the allele is paternally contributed. Exposure to methyl donor supplementation during midgestation shifts A vy phenotypes not only in the mice exposed as fetuses, but in their offspring. This finding indicates that methyl donors can change the epigenetic state of the A vy allele in the germ line, and that the altered state is retained through the epigenetic resetting that takes place in gametogenesis and embryogenesis. Thus a mother's diet may have an enduring influence on succeeding generations, independent of later changes in diet. Although other reports have suggested such heritable epigenetic changes, this study demonstrates that a specific mammalian gene can be subjected to germ-line epigenetic change.