An increased level of sperm abnormalities in mice with a partial deletion of the Y chromosome.
Two congenic lines of mice, one with a partial deletion of the Y chromosome, differ in the percentage of spermatozoa with abnormal heads: B10.BR/SgSn males give 22.6% and B10.BR-Ydel/Ms males give 64.2% abnormal sperm. The F1s resulting from crosses of B10.BR/SgSn males with females of five common inbred strains exhibited significantly lower levels of abnormal sperm than the parental strains, as opposed to F1 hybrids sired by B10.BR-Ydel/Ms mutant males, where very high levels of abnormal spermatozoa were found. About 30% of abnormal spermatozoa, produced by males with deletion on the Y chromosome, were characterized by a flat acrosomal cap. This class of abnormality was never observed in non-mutant males, suggesting a mutant-specific defect. These results demonstrate the important role of the Y chromosome in spermatogenesis.
Styrna
J
J
Department of Genetics and Evolution, Jagiellonian University, Krakow, Poland.
Imai
H T
HT
Moriwaki
K
K
D000818:Animals; D002872:Chromosome Deletion; D003433:Crosses, Genetic; D005260:Female; D007178:Inbreeding; D008297:Male; D051379:Mice; D013077:Sperm Head; D013091:Spermatogenesis / Q000235:genetics; D013094:Spermatozoa / Q000002:abnormalities*; D014998:Y Chromosome