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

Motility characteristics of epididymal sperm from tw32/+ and T/+ males of several strains were compared to those of sperm from the congenic, wild, type mice. Epididymal sperm from C57BL/6-tw32/+ (B6-tw32/+) 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: B6tw32/+, 32 micro/sec; C3H-tw32/+, 60; B6XC3H hybrids (F2*-tw32/+), 44; and C3HXB6 hybrids (F2-tw32/+), 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 micro/sec. B6-T2J/+ sperm had velocities intermediate to the congenic +/+ and tw32/+ genotypes, whereas C3HT/+ 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 tw32/+ males of all genotypes. Differences in motility patterns of sperm from tw32/+ males could play a role in the abnormally high transmission of tw32 through the male.