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bioRxiv · 10.1101/2020.08.15.252239

A maternal effect regulates global DNA methylation patterns

Loos, R.·Carola, V.·Audero, E.·Brini, E.·Lo Iacono, L.·Moles, A.·Bertone, P.·Gross, C. T.
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Abstract

Variation in DNA methylation between individuals has been shown to be influenced by both genetic and environmental factors. However, the relative impact of genetic and non-genetic factors on DNA methylation patterns across the mammalian genome has not been systematically studied. We performed whole-genome methylation analysis in two inbred mouse strains, revealing striking differences in the global distribution of DNA methylation. Although global methylation patterns were indistinguishable for most genomic features, a significant increase in the number of unmethylated CpG-island promoters and first exons was observed between strains. Experiments using F1 reciprocal hybrid strains demonstrated that the genotype of the mother dictated global DNA methylation patterns. Cross-fostering experiments ruled out a postnatal maternal effect on these differences and suggested that they were driven by a prenatal maternal effect, possibly via differential deposition of maternal gene products into the oocyte or uterine environment. These data demonstrate that maternal effects have a major impact on global DNA methylation patterns.

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Loos, R., Carola, V., Audero, E., Brini, E., Lo Iacono, L., Moles, A., Bertone, P., Gross, C. T.. 2020-08-15. A maternal effect regulates global DNA methylation patterns. https://doi.org/10.1101/2020.08.15.252239

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