The "spotted" locus maps to bovine chromosome 6 in a hereford-cross population

The spotted locus is responsible for several phenotypically distinguishable piebald patterns in cattle, including Hereford, or white face (S-H), lineb ack (S-P), and recessive spotting (s), in addition to non-spotted (S+). In a backcross mapping population, the S locus has been mapped by genetic link age to bovine chromosome 6, between microsatellite markers BM4528 and EL03. This region corresponds comparatively to a region on mouse chromosome 5 wh ich houses several coat color mutations, among which homology is possible w ith Hardy-Zuckerman 4 feline sarcoma viral oncogene homologue (Kil), patch (Ph), and rump white (Rw). Mutations at these loci resemble mutations at th e bovine S locus in both phenotype and mode of inheritance. Data are presen ted which show genetic linkage between the bovine S locus and microsatellit e markers on chromosome 6. Candidate genes for the bovine S locus are discu ssed.