Figure 1.

Fertility and germ cell production in Skp2-deficient male mice. (A) Fertility rate of male wild-type and mutant mice (2 to 4 months of age) as reflected by litter size when crossed with control C57BL/6 mice. Data are means ± SD for five animals per genotype. *P < 0.05 versus Skp2^+/+, †P < 0.05 versus Skp2^+/-. (B) Germ cell production in male wild-type and mutant mice. Epididymal sperm in 2-month-old mice were counted. Data are means ± SD for 8–12 mice per genotype. *P < 0.05 versus Skp2^+/+, †P < 0.05 versus Skp2^+/-.