A novel mouse chromosome 17 hybrid sterility locus: implications for the origin of t haplotypes.
The effects of heterospecific combinations of mouse chromosome 17 on male fertility and transmission ratio were investigated through a series of breeding studies. Animals were bred to carry complete chromosome 17 homologs, or portions thereof, from three different sources-Mus domesticus, Mus spretus and t haplotypes. These chromosome 17 combinations were analyzed for fertility within the context of a M. domesticus or M. spretus genetic background. Two new forms of hybrid sterility were identified. First, the heterospecific combination of M. spretus and t haplotype homologs leads to complete male sterility on both M. spretus and M. domesticus genetic backgrounds. This is an example of symmetrical hybrid sterility. Second, the presence of a single M. domesticus chromosome 17 homolog within a M. spretus background causes sterility, however, the same combination of chromosome 17 homologs does not cause sterility within the M. domesticus background. This is a case of asymmetrical hybrid sterility. Through an analysis of recombinant chromosomes, it was possible to map the M. domesticus, M. spretus and t haplotype alleles responsible for these two hybrid sterility phenotypes to the same novel locus (Hybrid sterility-4). Previous structural studies had led to the hypothesis that the ancestral t haplotype originated through an introgression event from M. spretus or a related species. If this were true, one might expect that (1) M. spretus homologs would be transmitted at a non-Mendelian ratio within the M. domesticus background, and (2) t haplotypes would be transmitted at a ratio closer to Mendelian within the M. spretus background.(ABSTRACT TRUNCATED AT 250 WORDS)
Department of Molecular Biology, Princeton University, New Jersey 08544-1014.
S H
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Pilder
M F
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Hammer
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Silver
D000818:Animals; D015139:Blotting, Southern; D002678:Chimera / Q000235:genetics*; D003433:Crosses, Genetic; D005808:Genes, Recessive / Q000235:genetics*; D006239:Haplotypes / Q000235:genetics; D007248:Infertility, Male / Q000235:genetics*; D008297:Male; D051379:Mice; D009154:Mutation / Q000235:genetics; D010641:Phenotype