Patterns of DNA variability at X-linked loci in Mus domesticus.
Introns of four X-linked genes (Hprt, Plp, Glra2, and Amg) were sequenced to provide an estimate of nucleotide diversity at nuclear genes within the house mouse and to test the neutral prediction that the ratio of intraspecific polymorphism to interspecific divergence is the same for different loci. Hprt and Plp lie in a region of the X chromosome that experiences relatively low recombination rates, while Glra2 and Amg lie near the telomere of the X chromosome, a region that experiences higher recombination rates. A total of 6022 bases were sequenced in each of 10 Mus domesticus and one M. caroli. Average nucleotide diversity (pi) for introns within M. domesticus was quite low (pi = 0.078%). However, there was substantial variation in the level of heterozygosity among loci. The two telomeric loci, Glra2 and Amg, had higher ratios of polymorphism to divergence than the two loci experiencing lower recombination rates. These results are consistent with the hypothesis that heterozygosity is reduced in regions with lower rates of recombination, although sampling of additional genes is needed to establish whether there is a general correlation between heterozygosity and recombination rate as in Drosophila melanogaster.
Nachman
M W
MW
Department of Ecology and Evolutionary Biology, University of Arizona, Tucson 85721, USA. nachman@ccit.arizona.edu
D053523:Amelogenin; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D004247:DNA; D003746:Dental Enamel Proteins / Q000235:genetics; D014644:Genetic Variation; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics; D007438:Introns; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D018991:Myelin Proteolipid Protein / Q000235:genetics; D018009:Receptors, Glycine / Q000235:genetics; D014960:X Chromosome
D053523:Amelogenin; C507200:Amelx protein, mouse; D003746:Dental Enamel Proteins; D018991:Myelin Proteolipid Protein; D018009:Receptors, Glycine; D004247:DNA; D007041:Hypoxanthine Phosphoribosyltransferase