Polymorphisms distinguishing different mouse species andthaplotypes

Abstract

SummaryThree anonymous chromosome 17 DNA markers,D17Tu36,D17Tu43, and D17Le66B, differentiate between house mouse species and/or betweentchromosomes. TheD17Tu36probe, which maps near theFulocus and to theIn(17)4ontchromosomes, identifies at least 15 haplotypes, each haplotype characterized by a particular combination of DNA fragments obtained after digestion with theTaqI restriction endonuclease. Ten of these haplotypes occur inMus domesticus, while the remaining five occur inM. musculus. In each of these two species, one haplotype is borne bytchromosomes while the other haplotypes are present on non-r chromosomes. TheD17Tu43probe, which maps near theD17Leh122locus and to theIn(17)3ontchromosomes, also identifies at least 15 haplotypes inTaqI DNA digests, of which nine occur in M. domesticus and six inM. musculus. One of the nineM. domesticushaplotypes is borne bytchromosomes, the other haplotypes are borne by non-f chromosomes; two of the sixM. musculushaplotypes are borne bytchromosomes and the remaining four by non-f chromosomes. Some of theD17Tu43haplotypes are widely distributed in a given species, while others appear to be population-specific. Exceptions to species-specificity are found only in a few mice captured near theM. domesticus-M. musculushybrid zone or in t chromosomes that appear to be of hybrid origin. TheD17Leh66Bprobe, which maps to theIn(17)2, distinguishes three haplotypes ofM. domesticus-dznved t chromosomes and one haplotype ofM. musculus-derivzd t chromosomes. Because of these characteristics, the three markers are well suited for the study of mouse population genetics in general and of t chromosome population genetics in particular. A preliminary survey of wildM. domesticusandM. musculuspopulations has not uncovered any evidence of widespread introgression of genes from one species to the other; possible minorintrogressions were found only in the vicinity of the hybrid zone. Typing of inbred strains has revealed the contribution of onlyM. domesticusDNA to the chromosome 17 of the laboratory mouse.