Fig. 4.

Brca2^wt/mut male rats contribute to rapid decline of litter size according with aging after mating with a Brca2^wt/wt female. (a) Top enriched gene sets in Brca2^wt/mut testes compared to Brca2^wt/wt by GSEA on testes from 10-week-old rats using gene set of “Human Phenotype Ontology” (n = 3). (b) Enrichment plots of the gene sets associated with male infertility. (c) Design of experiments evaluating the reproductive efficiency. (d) Trends of reproductive efficiency. Brca2^wt/mut male rats exhibited significant decrease in reproductive efficiency at 7 months of age in comparison to those of 6 months old whereas Brca2^wt/wt males did not show a significant decrease (Brca2^wt/wt, n = 5; Brca2^wt/mut, n = 7).