Fertile male mice with three sex chromosomes: evidence that infertility in XYY male mice is an effect of two Y chromosomes.
In the mouse XYY males are sterile, presumably because pairing abnormalities resulting from the presence of three sex chromosomes lead to meiotic breakdown. We have produced male mice, designated XYY*X, that have three sex chromosomes pairing regions but only one intact Y chromosome. Unexpectedly XYY*X, males are fertile, although they are no more efficient in sex chromosome pairing than previously reported XYY males. We conclude that the sterility of XYY males is caused by a combination of the deleterious effect of two Y chromosomes, presumably acting prior to meiosis, and pairing abnormalities resulting in significant meiotic disruption.
Hunt
P A
PA
Jackson Laboratory, Bar Harbor, ME 04609.
Eicher
E M
EM
D000818:Animals; D003433:Crosses, Genetic; D005260:Female; D005298:Fertility / Q000235:genetics; D007248:Infertility, Male / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D051379:Mice; D009929:Organ Size; D012729:Sex Chromosome Aberrations; D013737:Testis / Q000033:anatomy & histology; D014960:X Chromosome; D014998:Y Chromosome