Mouse sperm motility affected by factors in the T/t complex

Abstract

Motility characteristics of epididymal sperm from t^w32/+ and T/+ males of several strains were compared to those of sperm from the congenic, wild‐type mice. Epididymal sperm from C57BL/6‐t^w32/+ (B6‐t^w32/+) males showed a significant decline in vigorous motility and a significant increase in adhesivity to glass during 7.5 hours in vitro, while sperm from B6‐+/+ males showed no changes in these characteristics. The apparent mean velocities of epididymal sperm were: B6‐t^w32/+, 32 μ/sec; C3H‐t^w32/+, 60; B6XC3H hybrids (F₁*‐t^w32/+), 44; and C3HXB6 hybrids (F₁‐t^w32/+), 58. Each of these values was significantly lower than that of sperm from their congenic wild‐type strains: B6‐+/+, 115; C3H‐+/+, 177; F₁*‐+/+, 168 and F₁‐+/+, 195 μ/sec. B6‐T^2J/+ sperm had velocities intermediate to the congenic +/+ and t^w32/+ genotypes, whereas C3H‐T/+ sperm velocity was not significantly different from C3H‐+/+. These differences in measured sperm velocity may not reflect real differences in swimming speed, but rather may indicate a difference in the shape of swimming trajectories. Erratic and convoluted swimming trajectories were observed for the majority of sperm from t^w32/+ males of all genotypes. Differences in motility patterns of sperm from t^w32/+ males could play a role in the abnormally high transmission of t^w32 through the male.