W3 is one of the many different variations of white spotting.
¶ Phenotype
W3 often creates a near-white phenotype; but horses may retain flecks or regions of pigmented skin and hair, mainly at the topline (especially ears and poll) of the horse. Foals may be born with a pigmented topline, which then fades over time as the horse gets older. Typical white spotting characteristics are also present: the white patches often have irregular, jagged edges and white ticking is usually present in the pigmented areas.
W3 affects any base colour, but the presence of grey may make the white pattern harder to see. Since the pattern is usually very expressive, W3 may make it difficult to recognise the underlying colour of the horse without genetic testing.
| W3 - Arabian Horse |
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¶ Genotype
W3 is a white spotting mutation on the KIT locus (a nonsense mutation at exon 4). In real life, it is predicted to be embryonic lethal in the homozygous form. In Horse Reality, breeding two horses together that both have any of the white spotting alleles (W/n), will result in a failed pregnancy on the 4th day if the foal is W/W (25% chance). A homozygous white spotting foal will, therefore, never be born.
Below, the resulting phenotype of each genotype is listed:
- W3/Wx = Failed pregnancy
- W3/n = White spotting 3
- n/n = No white spotting
W3 can be tested at the Laboratory.
¶ Breeds
The W3 allele is found in Arabian Horses descended from R Khasper, a near-white stallion born in 1996. He was born to 2 solid parents, and it has been concluded that the mutation took place spontaneously in the Arabian stallion. The following table lists all breeds that can currently have the W3-allele in-game.
| Breeds |
| Akhal-Teke Horse |
| Arabian Horse |
| Brabant Horse |
| Brumby Horse |
| Camargue Horse |
| Cleveland Bay |
| Exmoor Horse |
| Finnhorse |
| Fjord Horse |
| Friesian Horse |
| Haflinger Horse |
| Icelandic Horse |
| Irish Cob Horse |
| Kladruber Horse |
| Knabstrupper |
| Lipizzaner |
| Lusitano |
| Mongolian Horse |
| Mustang Horse |
| Namib Desert Horse |
| Noriker Horse |
| Norman Cob |
| Oldenburg Horse |
| Pantaneiro Horse |
| Pura Raza Española |
| Quarter Horse |
| Shetland Pony |
| Shire Horse |
| Suffolk Punch |
| Thoroughbred |
| Trakehner Horse |
| Welsh Pony |
¶
References
- Bellone R., Sponenberg D. P., Equine Color Genetics, 4th Edition, 2017, Wiley-Blackwell,
- Castle N., Equine KIT Gene Mutations, Dun Central Station, 2009
- The University of Sydney, Online Mendelian Inheritance in Animals (OMIA); https://omia.org/OMIA000209/9796/; Access: December 2022
- R Khasper horse pedigree; https://www.allbreedpedigree.com/r+khasper; Access: December 2022