A QTL for the degree of spotting in cattle shows synteny with the KIT locus on chromosome 6

Abstract

The proportion of unpigmented coat on the trunk was determined from photographs of 38 German Simmental and 627 German Holstein bulls distributed over three generations. All 665 animals were members of 18 Holstein and 3 Simmental half-sib families. A Bayesian estimation of heritability yielded a posterior mean of 0.88 and a standard error of 0.08. A quantitative trait loci (QTL) scan over all chromosomes covered by 229 microsatellite marker loci (2926 cM) was performed by fitting a multiple marker regression model to 625 observations from the youngest generation in 18 families. On chromosome 6 a QTL for the proportion of white coat with large effects (experiment-wise error probability < .0001) was found and a less important one on chromosome 3 (chromosome-wise error probability < .009). Chromosome 6 is known to harbor the KIT locus (receptor tyrosinase kinase), which is associated with various depigmentation phenotypes in mice, humans, and pigs. Similarity of phenotypic KIT effects in other species and synteny with the reported QTL suggest that KIT is a serious candidate gene for the degree of spotting in cattle. The results are also discussed with respect to resistance to solar radiation, heat stress, and photosensitization.

Analysis of SNPs in the KIT gene of cattle with different coat colour patterns and perspectives to use these markers for breed traceability and authentication of beef and dairy products

“…On the other hand, it is interesting to note that only the [C:A] and [T:G] haplotypes were identified in the spotted breeds (even if here we analysed markers in a small portion of the KIT gene). This might be in agreement to the QTL experiments that located a multi-allele QTL for the degree of spotting on BTA6 in the region containing the KIT gene (Reinsch et al, 1999 , 2009), suggesting that the KIT gene might affect the extension of the spotted areas in spotted breeds. AMOVA based on single markers (averaged) or haplotypes showed that genetic variation between spotted and nonspotted groups of breeds amounted to 25.3% (16.8% for the g.72779776C>T SNP and 9.5% for the g.72783182A>G SNP) or 21.2% of total variation (P<0.05 and P<0.10, respectively), supporting a possible involvement of the KIT gene in influencing the spotted phenotype, but probably not determining it (at least in all animals), as already suggested (Fontanesi et al, 2010).…”

“…In the same chromosome region, Reinsch et al (1999) and Liu et al (2009) localized a QTL for the degree of spotting in German Holstein-Friesian and Simmental cattle and in a Holstein-Friesian x Jersey cross. The KIT gene encodes the mast/stem cell growth factor receptor that is involved in melanogenesis driving the melanocyte migration from the neural crest along the dorsolateral pathway to colonize the final destination in the skin (Besmer et al, 1993).…”

Determination of Genetic Diversity among Korean Hanwoo Cattle Based on Physical Characteristics

“…White hairs appear in cows to various degrees. These include roan coat coloring (Seitz et al, 1999; Aasland et al, 2000) characterized by a mix of white or black hair similar to the white or black hair of Hanwoo, white spotting with spots shaped like the white spot in Hanwoo (Olsen, 1981, 1999; Reinsch et al, 1999), the color-sided type (Olson, 1999) in which a side of the body is covered with large spot, the belted type (Rao et al, 2003) featureing a belted waist, and an albino type in which the entire body is covered with white hair (Leipold et al, 1968; Schmutz et al, 2004; Seo et al, 2007). In particular, appearance of the roan coat coloring, which is similar to white hair of Hanwoo, is determined by expression of the Mast Cell Growth Factor (MGF) gene (also called KIT ligand) located in chromosome number 5 and arises from a single base pair mutation (Seitz et al, 1999; Aasland et al, 2000).…”

“…Expression of white spots is determined by synteny of KIT in the sixth chromosome of Holstein and Hereford cattle (Reinsch et al, 1999), and appearance of the four distinct spot shapes depend upon alleles in S and W locus ( S + , S H , S p , and s ). The s allele was responsible for irregular spot shapes such as those seen in Holstein or Guernsey cattle while the S H allele was expressed in breeds such as Hereford with white spots on the head.…”

Identification of a major locus interacting with MC1R and modifying black coat color in an F2 Nellore-Angus population

“…Mutations in KIT cause pigmentation defects and patterns in several species (as reviewed by Fontanesi et al [18]), and QTL for spotting have been found at or near KIT in cattle [18-20]. The frequency of any spotting (body or face) among E D E + heterozygotes in this study was 0.2, so to confirm that the QTL detected was indeed degree of black and not a false positive association with spotting, two additional analyses were performed.…”