High-resolution genetic mapping of the sucrose octaacetate taste aversion (Soa) locus on mouse Chromosome 6

An acetylated sugar, sucrose octaacetate (SOA), tastes bitter to humans and has an aversive taste to at least some mice and other animals. In mice, ta ste aversion to SOA depends on allelic variation of a single locus, Soa. Th ree Soa alleles determine 'taster' (Soa(a)), 'nontaster' (Soa(b)), and 'dem itaster' (Soa(c)) phenotypes of taste sensitivity to SOA. Although Soa has been mapped to distal Chromosome (Chr) 6, the limits of the Soa region have not been defined. In this study, mice from congenic strains SW.B6-Soa(b), B6.SW-Soa(a), and C3.SW-Soa(a/c) and from an outbred CFW strain were genoty ped with polymorphic markers on Chr 6. In the congenic strains, the limits of introgressed donor fragments were determined. In the outbred mice, linka ge disequilibrium and haplotype analyses were conducted. Positions of the m arkers were further resolved by using radiation hybrid mapping. The results show that the Soa locus is contained in a similar to1-cM (3.3-4.9 Mb) regi on including the Prp locus.