Fig. 1

Changes in total genomic CpG methylation from gametes to blastocyst. a Line charts show global DNA methylation across the indicated stages in pig, cow, mouse and human. The mouse datasets are from Smith et al. [66] and Guo et al. [21]; the human datasets from Smith et al. [65] and Zhu et al. [77] Global DNA methylation at specific genomic features is shown for porcine (b) and bovine (c) samples. For the transitions from gametes to the 2–4 cell stages, dotted lines represent sperm data, and solid lines correspond to oocyte data