抄録
A new t-mutant, tM, was isolated from our laboratory mouse stock. The new t-haplotype is a recombinant recovered as tM tf in T tf/tw18+tf×T tf/tw18 +tf matings, tM is viable under homozygous conditions. The transmission ratio of tM was calculated to be 0.30. Not all tM/tM males are sterile, although the frequency of sterile males may be higher compared to the wild-type.