Close linkage of the murine locus bare patches to the X-linked visual pigment gene: implications for mapping human X-linked dominant chondrodysplasia punctata.
The murine X-linked dominant mutation bare patches (Bpa) has a phenotype similar to and is likely homologous to human X-linked dominant chondrodysplasia punctata (CDPX2). Classic two-point linkage analysis in the mouse with distant markers suggested that Bpa maps near glucose-6-phosphate dehydrogenase (G6pd). We have confirmed the regional localization using interspecific matings with Mus spretus. We have also detected a restriction fragment length polymorphism (RFLP) at the murine X-linked visual pigment (Rsvp) locus in inbred Bpa females using the restriction enzyme PstI. Cumulative data from segregation of alleles using the PstI RFLP and analysis of interspecific backcross progeny at the Rsvp locus suggest that Bpa is tightly linked to Rsvp. Thus, the human CDPX2 gene probably maps within Xq27-Xq28 and not within Xp22.3-Xpter, where deletions associated with X-linked recessive chondrodysplasia punctata (CDPX) have been noted. This strategy should be applicable to the fine mapping of other dominant murine mutations.
Herman
G E
GE
Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030.
Walton
S J
SJ
D000818:Animals; D002806:Chondrodysplasia Punctata / Q000235:genetics*; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D005260:Female; D005796:Genes; D005799:Genes, Dominant; D008040:Genetic Linkage; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics; D006801:Humans; D008297:Male; D051379:Mice; D009115:Muridae; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length; D012168:Retinal Pigments / Q000235:genetics*; D014960:X Chromosome
D012168:Retinal Pigments; D005954:Glucosephosphate Dehydrogenase; C024388:CTGCAG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific