Number of mature epididymal sperm from WT (white bar), Spatc1l+/- (gray bar), and Spatc1l-/- (black bar) mice. Sperm were collected from the vas deferens. The average number of mature sperm in WT, Spatc1l+/-, and Spatc1l-/- males was (4.06 ± 0.40) × 106, (3.7 ± 0.7) × 106, and (3.93 ± 0.90) × 106, respectively. Data are presented as means ± s.d. (n = 5). 