Fig. 2

Schematic representation of some aspects of sperm DNA damage and their putative consequences if not repaired. The upper left insert illustrates the major alterations suffered by the sperm DNA from strand breaks, alterations of epigenetic marks and base oxidative damage (such as the 8-OHdG residue. It also show the preferential sites where such alterations preferentially occurs corresponding to the genomic regions of lesser compaction still in nucleosomal organization (histone solenoids within the protamine-containing toroidal donuts, and the small DNA linkers associating protamine donuts. The upper right insert depicts the oocyte repair capacity that has the task to repair the paternal DNA. The lower left insert shows a harmonious development while the lower right panel illustrates some of the classical consequences of oocyte failure/inability to repair the paternal DNA alterations