W16 is one of the many different variations of white spotting.
¶ Phenotype
Horses with W16 exhibit a range of phenotypes. It typically results in nearly white horses, but they may also show irregular white patches on the legs, belly and head. Foals may retain flecks or regions of pigmented skin and hair, mainly at the topline (especially ears and poll), which then typically fade over time as the horse gets older.
W16 affects any base colour, but the presence of dilutions or grey may make the white pattern harder to see. When the pattern is very expressive, W16 may make it difficult to recognise the underlying colour of the horse without genetic testing.
| W16 - Oldenburg Horse |
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¶ Genotype
W16 is a white spotting mutation on the KIT locus (a frameshift mutation at exon 7). No horses homozygous for W16 have been recorded; therefore, it is suspected to be embryonic lethal in real life. 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:
- W16/Wx = Failed pregnancy
- W16/n = White spotting 16
- n/n = No white spotting
W16 can be tested at the Laboratory.
W16 can, of course, also be present together with other KIT alleles - however, since they are located on the same gene, horses can only be heterozygous:
- TO/W16 = Tobiano white spotting 16
¶ Breeds
The founder of the W16 mutation is suspected to be the Oldenburg mare Celine, born in 2003. The following table lists all breeds that can currently have the W16-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 |
| Kathiawari 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 |
¶
Changelog
- On March 24th 2026, W16 was added to the game. It was made available in the foundation for three months (March 24th-June 24th) as a time-limited event[5]
¶ References
- Bellone R., Sponenberg D. P., Equine Color Genetics, 4th Edition, 2017, Wiley-Blackwell,
- Haase, B., et. al., Five novel KIT mutations in horses with white coat colour phenotypes, Animal Genetics, 2011
- The University of Sydney, Online Mendelian Inheritance in Animals (OMIA); https://omia.org/OMIA000209/9796/; Access: December 2022
- Celine horse pedigree; https://www.allbreedpedigree.com/celine87; Access: March 2026
- https://v2.horsereality.com/news/278/art-release-w16-added-to-oldenburg-horses