Submitted to: Journal of Heredity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 1, 1999
Publication Date: N/A
Interpretive Summary: Hereford cattle have a higher than normal incidence of Bovine Ocular Squamous Cell Carcinoma (BOSCC or "cancer eye"). One possible mechanism for the development of BOSCC involves a DNA mutation which coincidently affects coat color pattern. To study possible correlations between BOSCC and white-faced cattle, the gene causing white-face has been mapped to bovine chromosome 6. Most genes found on bovine chromosome 6 are located on chromosome 5 in the laboratory mouse. Mouse chromosome 5 also contains several genes which affect coat color. By comparing phenotypes, it is proposed that the gene causing white-face in cattle is the bovine homolog of one of several mouse genes, including Hardy- Zuckerman 4 feline sarcoma viral oncogene homolog (Kit), recessive spotting (rs), Patch (Ph), or Rump white (Rw). The potential homology of white-face with Kit oncogene is quite interesting, given the role oncogenes are known to play in the development of carcinoma and other tumor types. Further localization of the gene causing white-face will allow a more definitive assignment of homology, as well as further insights into the role that white-face plays in the development of BOSCC. Possible outcomes of this research include the development of screening procedures to reduce or eliminate BOSCC in cattle herds.
Technical Abstract: The spotted locus is responsible for several phenotypically distinguishable piebald patterns in cattle, including Hereford, or white face (SH), lineback (SP), and recessive spotting (s), in addition to non-spotted (S+). In a backcross mapping population, the S locus has been mapped by genetic linkage to Bovine chromosome 6, centromeric to BM4528. This regions corresponds comparatively to a region on mouse chromosome 5 which houses several coat color mutations, among which homology is possible with Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (Kit), recessive spotting (rs), Patch (Ph), or Rump white (Rw). Mutations at these loci resemble mutations at the bovine S locus in both phenotype and mode of inheritance. Data are presented which show genetic linkage between the bovine S locus and microsatellite markers on chromosome 6. Candidate genes for the bovine S locus are discussed.