General Description for Dominant White 24

Dominant White 24 (W24) is found in Trottatore Italianos and may result in a full white coat.

W24 Founder: Via Lattea, Trottatore Italiano stallion

W24 Phenotype: Full white

Gene Information

W24 is a missense mutation on exon 4. KIT is a tyrosine kinase receptor that is vital for normal development. Mutations in other species have led to white spotting, anemia, sterility, and certain types of tumors. Negative health effects associated with dominant white have not been documented in the horse, although some horse owners have reported health issues in some homozygotes of certain Ws while some Ws are homozygous lethal. The various W alleles encompass a variety of mutations, all resulting in changes to the encoded protein. The W24 variant is a mutation that disrupts splicing of the KIT gene. The founder is a white Trottatore Italiano named Via Lattea, born in 2014.

References

Haase B et al., “Allelic heterogeneity at the equine KIT locus in dominant white (W) horses.” (2007) PLoS Genet. 3: e195.

Haase B et al., “Seven novel KIT mutations in horses with white coat colour phenotypes.” (2009) Anim Genet. 40: 623-9.

Holl H et al., “De novo mutation of KIT discovered as a result of a non-hereditary white coat colour pattern.” (2010) Anim Genet. 41: 196-8.

Haase B et al., “Five novel KIT mutations in horses with white coat colour phenotypes.” (2011) Anim Genet. 42: 337-9.

Hauswirth R et al., “Novel variants in the KIT and PAX3 genes in horses with white-spotted coat colour phenotypes.” (2013) Anim Genet. 44: 763-5.

Holl H et al., “A novel splice mutation within equine KIT and the W15 allele in the homozygous state lead to all white coat color phenotypes.” (2017) Anim Genet. DOI: 10.1111/age.12554

Durig N et al., “Whole genome sequencing reveals a novel deletion variant in the KIT gene in horses with white spotted coat colour phenotypes.” (2017) Anim Genet. In press.