Fig. 8

Dynamics of global DNA hydroxymethylation in the paternal (pPN) and the maternal (mPN) pronucleus. No differences in the normalized levels of 5hmC (5hmC/DNA) were observed between the pronuclear stages in pPN or the mPN. However, the levels of normalized 5hmC were significantly higher in the maternal PN2 than its paternal counterpart and in the paternal PN3 than its maternal counterpart (*). A significant increase in the levels of total 5hmC (5hmC) was found in the pPN between PN1 versus PN3 and in the mPN between PN1 vs. PN2–PN3–PN4. Additionally, a significant increase in the total DNA fluorescence (DNA) was observed between PN1 and PN3–PN4, in both pPN and mPN. The distribution of the 81 embryos included in the study was: PN1 (n = 13), PN2 (n = 34), PN3 (n = 19) and PN4 (n = 15). Different superscripts (a or b) indicate significant differences, and p values <0.05 were considered significant