Epigenetic modifications established during gametogenesis regulate transcription and other nuclear processes in gametes, but also have influences in the zygote, embryo and postnatal life. This is best understood for DNA methylation which, established at discrete regions of the oocyte and sperm genomes, governs genomic imprinting. In this review, we describe how imprinting has informed our understanding of de novo DNA methylation mechanisms, highlight how recent genome-wide profiling studies have provided unprecedented insights into establishment of the sperm and oocyte methylomes and consider the fate and function of gametic methylation and other epigenetic modifications after fertilization.

Biotech Research and Innovation Centre University of Copenhagen DK2200 Copenhagen Denmark

Epigenetics Programme The Babraham Institute Cambridge CB22 3AT UK

Laboratory of Developmental Biology and Genetics Department of Molecular Biology University of South Bohemia 37005 České Budějovice Czech Republic

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Expression analysis suggests that DNMT3L is required for oocyte de novo DNA methylation only in Muridae and Cricetidae rodents

An Interplay between Epigenetics and Translation in Oocyte Maturation and Embryo Development: Assisted Reproduction Perspective

Transcription and chromatin determinants of de novo DNA methylation timing in oocytes