Mouse male sterility and histoincompatibility (mshi) maps between the D10Mit51/168/212 cluster and D10Mit213

The recessive male sterility and histoincompatibility (mshi) mutation in th e mouse generates pleiotropic effects on graft transplantation and male rep roduction. Previous analysis of backcross mice typed for mshi either by tes ticular morphology or by allograft rejection has located each trait to a 20 -cM region on proximal mouse Chr 10, Here we present the microsatellite pol y-morphism analysis of a new 276-member intraspecific backcross panel-inclu ding a set of 135 males typed for sterility and histoincompatibility-that p laces both features controlled by mshi within a 1.7-cM interval between mar kers D10Mit51/168/212 and D10Mit213. In addition, this analysis has allowed an explicit test of a two-gene model for the mshi locus and has provided a measurement of the penetrance of the mshi-generated histogenic phenotype i n both male (88.4 +/- 3.9%) and female (91.0 +/- 3.5%) mutants. The fine-st ructure map presented should facilitate a chromosome walk across this regio n and, ultimately, the molecular identification of the gene or genes affect ed by this interesting mutation.