A review on the evaluation of horse coat color
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Accepted 2026-04-28
Published 2026-06-02
Abstract
The coat color diversity of horses represents a classic example of the genetic and evolutionary effects of domestication. While wild equids exhibited limited pigmentation patterns, human-mediated selection has dramatically expanded phenotypic and genetic variation among domestic horses. This variation is influenced by multiple interacting loci, with some genes exerting pleiotropic effects on physiological and morphological traits. Modern molecular genetics has identified key loci controlling base colors (Agouti, Extension), dilution (D locus), greying (G locus), and patterned phenotypes including Tobiano and Overo, while also highlighting the increasing importance of additional white patterning mechanisms such as MITF and PAX3-associated Splashed White phenotypes and KIT gene complex variants (e.g., Sabino 1 and W1–W30 alleles). Furthermore, some coat color–associated mutations illustrate the fitness costs of selection, as seen in Overo Lethal White Syndrome (OLWS) and the association between the Silver dapple mutation and Multiple Congenital Ocular Anomalies (MCOA), emphasizing the pleiotropic and sometimes deleterious effects of pigmentation genes). Quantitative assessment using Lab* color metrics allows objective evaluation of coat pigmentation and facilitates comparisons across breeds, ages, and sexes. Phenotypic studies show that coat color does not directly correlate with performance or temperament but may affect thermoregulation, predator avoidance, disease susceptibility, and market value. Comparative research on other livestock species confirms that coat color is largely polygenic, heritable, and influenced by human selection. Integrating molecular and phenotypic analyses enhances our understanding of the evolutionary, genetic, and practical implications of coat color variation in horses. These insights support breeding decisions, breed identification, and the conservation of genetic diversity. Overall, the study of equine coat pigmentation provides a valuable model for investigating domestication, human-driven selection, and the genetic architecture of complex traits in livestock species.
References
- Adalsteinsson, S. (1970): Colour inheritance in Icelandic sheep and relation between colour, fertility and fertilization. Journal of Agricultural Researches in Iceland. 2., 3–135.
- Adalsteinsson, S. (1978): Inheritance of yellow dun and blue dun in the Icelandic toelter horse. Journal of Heredity. 69. 146–148. p. https://doi.org/10.1093/oxfordjournals.jhered.a108913
- Adalsteinsson, S.; Hersteinsson, P.; Gunnarsson, E. (1987): Fox colors in relation to colors in mice and sheep. Journal of Heredity. 78. 235–237. p. https://doi.org/10.1093/oxfordjournals.jhered.a110373
- Andersson, L.; Sandberg, K. (1982): A linkage group composed of three colour genes and three serum protein loci in horses. Journal of Heredity, 73(2): 91–94. https://doi.org/10.1093/oxfordjournals.jhered.a109606
- Andersson, L.; Georges, M. (2004): Domestic-animal genomics: Deciphering the genetics of complex traits. Nature Reviews Genetics, 5(3), 202–212. https://www.nature.com/articles/nrg1294
- Animal genetics (2025): https://animalgenetics.com/horse-coat-color-calculator/ 2025.12.25.
- Blesa, F.; Valera, M.; Vinuesa, M.; Molina, A. (1999): The gestation length of the Andalusian and Arabian Horse. Book of Abstracts 5, 50th An. Meeting of Europ. Ass. for Animal Prod., Zurich (Switzerland). Copyright Wageningen Pers, Wageningen, pp. 348.
- Bodó, I.; Hecker, W. (1998): Lótenyésztők kézikönyve. Mezőgazdasági Kiadó, Bp. 429 p. ISBN: 978 963 286 102 9
- Bowling, A.T.; Ruvinsky, A. (1995): Horse Genetics. CAB International. ISBN: 978-0-85199-429-1
- Bowling, A.T. (1996): White, grey and roan. Horse Genetics. CAB International, Wallingford. Oxon, UK. 34–41. p. ISBN: 978 0851991016
- Bowling, A.T. (2000): Genetics of colour variation. In: Bowling, A.T., Ruvinsky, A. (Eds.), CABI Publishing, Wallingford, U.K., pp. 53–70. ISBN: 978 0851994291.
- Brandsch, H.; Gerber, J. (1987): The inheritance of markings in horses. 4. Working hypothesis to explain the relationship between inheritance of colour and markings. Archiv für Tierzucht. 31. 385–390.
- Brooks, S.A.; Lear, T.L.; Adelson, D.L.; Bailey, E. (2007): A chromosome inversion near the KIT gene and the Tobiano spotting pattern in horses. Cytogenetic and Genome Research, 119 (3–4), 225–230. https://doi.org/10.1159/000112065
- Castle, W.E. (1953): Coat color inheritance in horses and other mammals. Genetics. 39. 35–47. https://doi.org/10.1093/genetics/39.1.35
- Cena, M.; Czyszek, W.; Słomka, J. (1957): Badania nad wpływem umaszczenia koni na pochłanianie promieniowania słonecznego. Med. Wet., 6: 261–264. https://doi.org/10.2478/v10020-007-0005-8
- Craig, L.; Van Vleck, L.D. (1985): Evidence for inheritance of the red dun dilution in the horse. Journal of Heredity. 76. 138–139. https://doi.org/10.1093/oxfordjournals.jhered.a110042
- Cruz, A.; Yucra, A.; Guriérrez, G.A.; Burgos, A.; Morante, R.; Gutiérrez, J.P. (2021): Colorimetry analysis of coat color and its relationship with fiber traits in alpacas. Animal, Vol. 15, 100219. https://doi.org/10.1016/j.animal.2021.100219
- Curik, I.; Seltenhammer, M.; Sölkner, J. (2002): Quantitative genetic analysis of melanoma and grey level in Lipizzan horses. WCGALP Organizing Committee (Ed.), Proceedings 7th World Congress on Genetics Applied to Livestock Production, 19–23.8. 2002, Montpellier, F; CD-ROM: ISBN 2-7380-1052-0, Communication No, 05-09.
- Curik, I.; Seltenhammer, M.; Tóth, ZS.; Niebauer, G.; Sölkner, J. (2004): Quantitative inheritance of the coat greying process in horse. 55th Annual Meeting of the European Association for Animal Production (EAAP), H4.6, Bled, 316. p.
- Darwin, C. (1859): The Origin of Species. John Murray, London. Penguin Books, Harmondsworth, England, 1968, pp. 71–100.
- Diamond, J. (2002): Evolution, consequences and future of plant and animal domestication. Nature, 418(6898), 700–707. http://dx.doi.org/10.1038/nature01019
- Dohy, J. (1999): Genetika állattenyésztőknek. Mezőgazda Kiadó, Bp. 33. p. ISBN: 9639239410
- Dring, L.A.; Hintz, H.F.; Van Vleck, L.D. (1981): Coat color and gestation length in Thoroughbred mares. J. Hered., 72: 65–66. https://doi.org/10.1093/oxfordjournals.jhered.a109433
- Druml, T.; Grilz-Seger, G.; Horna, M.; Brem, G. (2018): Discriminant analysis of colour measurements reveals allele dosage effect of ASIP/MC1R in bay horses. Czech J. Anim. Sci., 63, 347–355. p. https://doi.org/10.17221/105/2017-CJAS
- Edwards, M.D.; Stuber, C.W.; Wendel, J.F. (1987): Molecular-marker facilitated investigations of quantitative-trait loci in maize. I. Numbers, genomic distribution and types of gene action. Genetics, 116: 113–125. https://doi.org/10.1093/genetics/116.1.113
- Equine genetics (2025): University of California, Davis, Veterinary Medicine & Veterinary Genetics Laboratory. https://vgl.ucdavis.edu/ 2025.12.28.
- ESTESWORTH, B. (1948): Lack of correlation between coat colour and temperament. Journal of Heredity, 39: 84. https://doi.org/10.1093/oxfordjournals.jhered.a105804
- Etalon (2026): https://etalondx.com/horse-dna-tests/ 2026.01.02.
- Falconer, D.S. (1981): Introduction to quantitative genetics. Longman Group Ltd, New York, USA, pp. 41, 281. ISBN: 978 0582441958
- Fang, M.; Larson, G.; Soares Ribeiro, H.; Li, N.; Andersson, L. (2009): Contrasting Mode of Evolution at a Coat Color Locus in Wild and Domestic Pigs. PLoS Genet. 2009;5:e1000341. https://doi.org/10.1371/journal.pgen.1000341
- FAOSTAT (2025): http://www.faostat.fao.org. 2025.12.01.
- Gremmel, F. (1939): Coat color in horses. Journal of Heredity. 30. 437–445. p. https://doi.org/10.1093/jhered/30.10.437
- Grilz-Seger, G.; Mesarič, M.; Brem, G.; Cotman, M. (2021): Characterisation of coat colour in the Slovenian Posavje Horse. Slovenian Veterinary Research. 58(2): 77–84.p. https://doi.org/10.26873/SVR-1091-2020
- Ha, T.; Javedan, H.; Watertson, K.; Naysmith, L.; Rees, J.L. (2003): The relationship between constitutive pigmentation and sensitivity to ultraviolet radiation induced erythema is dose-dependent. Pigment Cell Research. 16: 477–479. https://doi.org/10.1034/j.1600-0749.2003.00076.x
- Henner, J. (2000): Molekulargenetische Untersuchungen der Fellfarbvererbung beim Pferd unter besonderer Berücksichtigung der Freibergerrasse. Dissertation am Institut für Nutztierwissenschaften der Veterinärmedizinischen Fakultät und der ETH Zürich, Abt. Züchtungsbiologie.
- Henner, J.; Poncet, P.A.; Guerin, G.; Hagger, C.H.; Stranzinger, G.; Rieder, S. (2002): Genetic mapping of the (G)-locus, responsable for the coat color phenotype "progressive greying with age" in horses (Equus cabaluus). Mammalian Genome, 13. 535–537. https://doi.org/10.1007/s00335-002-2174-7
- Hofmanová, B.; Vostrý, L.; Vostrá-Vydrová, H.; Dokoupilová, A.; Majzlík, I. (2019): Estimation of genetic and non-genetic effects influencing coat colour in black horses. Czech Journal of Animal Science, 64(1): 41–48. https://doi.org/10.17221/136/2018-CJAS
- Horn, A. (1971): Állattenyésztési enciklopédia. Mezőgazdasági Kiadó, Budapest.
- Horn, A. (1976): Állattenyésztés. Első kötet. Mezőgazdasági Kiadó, Bp. 103–106.
- Hyland, A. (1999): The Quarter Horse. ISBN: 9780851315058
- Jackson, I.J. (1994): Molecular and developmental genetics of mouse coat color. Annual Review of Genetics. 28. 189–217. https://doi.org/10.1146/annurev.ge.28.120194.001201
- Jones, W.E. (1982): Genetics and Horse Breeding. Lea and Febiger. Philadelphia. 101–102.. ISBN: 978 0812107210
- Kasarda, R.; Šidlová, V.; Pavlík, I.; Moravčíková, N.; Kadlečík, O. (2016): Inheritance of coat colour in Slovak Pinzgau cattle. Journal of Central European Agriculture, 17(1), 48–55. https://doi.org/10.5513/JCEA01/17.1.1668
- Keeler, C.E. (1947): Coat color, physique, and temperament. Journal of Heredity, 38: 271–279. https://doi.org/10.1093/oxfordjournals.jhered.a105747
- Klungland, H.; Vage, D.I. (2000): Molecular genetics of pigmentation in domestic animals. Curr. Genomics, 1(3): 223–242. https://doi.org/10.2174/1389202003351364
- Kuli, Gy. (1998): A ló fakó színöröklődésének vizsgálata. Diplomadolgozat. Debreceni Agrártudományi Egyetem. 5–14.
- Lanzillotti, I.; Buonsanti, N. (1893): Manuale del Veterinario Practico. Milano
- Lauvergne, J.J. (1989): La constitution des resources génétiques animals de ferme. In: P. Molénat et E. Verrier (Editors), la gestion des ressources génétiques des especes animals domestiques. Coll. Paris, 18–19 April 1989, Bureau des Ressources Génétiques, Paris, 10–18.
- Lehmann, E. (1975): Zur Farbgenetik des Pferdes unter besonderer Berücksichtigung der Wildformen, Zeitschrift für Tierzüchtung und Züchtungsbiologie. Hamburg, 1–2. 106–117.
- Librado, P.; Khan, N.; Fages, A. et al. (2021): The origins and spread of domestic horses from the Western Eurasian steppes. Nature, 598(7882), 634–640. http://doi.org/10.1038/s41586-021-04018-9.
- Lindgren, G.; Sandberg, K.; Persson, H.; Marklund, S.; Breen, M.; Sandberg, B.; Carlsten, J.; Ellegren, H. (1998): A primary male autosomal linkage map of the horse genome. genome research. 8. 951–966. https://doi.org/10.1101/gr.8.9.951
- Locke, M.M.; Ruth, L.S.; Millon, L.V.; Penedo, M.C.T.; Murray, J.D.; Bowling, A.T. (2001): The cream dilution gene, responsible for the palomiono and buckskin coat colours, maps to horse chromosome 21. Animal Genetics. 32. 340-343. https://doi.org/10.1046/j.1365-2052.2001.00806.x
- Locke, M.; Penedo, M.C.T.; Brickner, S.J.; Millon, L.V.; Murray, J.D. (2002): Linkage of the grey coat colour locus to microsatellites on horse chromosome 25. Animal Genetics. 33. 329–337. https://doi.org/10.1046/j.1365-2052.2002.00885.x
- Mariat, D.; Taourit, S.; Guérin, G. (2003): A mutation in the MATP gene causes the cream coat colour in the horse. Genetic Selection Evolution. 35. 119–133. https://doi.org/10.1186/1297-9686-35-1-119
- Marklund, L.; Johansson, M.K.; Anderson, L. (1996): A missense mutation in the gene for melanocyte-stimulating hormone receptor (MC1R) is associated with the chesnut coat color in horses. Mammalian Genome. 7. 895–899. https://doi.org/10.1007/s003359900264
- Meregalli, A. (1980): Morphological analysis of domestic animals. Liviana Edition. Padova
- Mihók, S. (1994): A póniló. Mezőgazda Kiadó, Bp. 35–37. ISBN: 9638439207
- Moellmann, G.; Slominski, A.; Kuklinska, E.; Learner, A.B. (1988): Regulation of melanogenesis in melanocyte. Pigment Cell Res. 1, 79–87. https://doi.org/10.1111/j.1600-0749.1988.tb00798.x
- NEOGEN (2025): GGP GeneSeek Genomic Profiler Equine, file:///C:/Users/user/Downloads/Official_GGP-Equine_Tech-Sheet.pdf 2025.05.05.
- Nürnberg, H. (1993): Der Lipizzaner. Die neue Brehm-Bücherei Band 613. 61–65. ISBN 978 3 89432 404 9
- Odriozola, M. (1951): A los Colores del caballo. Publicationes del Dindicatio Nacional de Ganaderia, Madrid. ISBN: 978 84 7479 941 5
- Overton, R. (2001): Positively Perlino. Paint Horse Journal. 22. 72–78.
- Ócsag, I. (1990): Kis magyar lovaskönyv. Ko-libri Kiadó, Bp.
- Patterson Rosa, L.; Martin, K.; Vierra, M.; Lundquist, E; Foster, G.; Brooks, S.A.; Lafayette, C. (2022): A KIT Variant Associated with Increased White Spotting Epistatic to MC1R Genotype in Horses (Equus caballus). Animals, 12(15), 1958; https://doi.org/10.3390/ani12151958
- Price, E.O. (1999): Behavioral aspects of animal domestication. Quarterly Review of Biology, 74(1), 1–23. https://doi.org/10.1016/S0168-1591(99)00087-8
- Pruski, W. (1959): Dzikie konie wschodniej Europy. Rocz. Nauk Rol., D-85: 1–131.
- Radácsi, A.; Bodó, I.; Béri, B. (2007): Additional data for the evaluation of coat colour varieties in the Hungarian Grey cattle. Acta Agraria Debreceniensis, 26, 44–47. https://doi.org/10.34101/actaagrar/26/3053
- Reismann, M.; Wagner, H.J.; Leuthold, G. (1998): Detection of the fox allele in the Norwegian Fjord horse. XXVII. Óvári Tudományos Napok. Poszter.
- Reismann, M.; Wagner, H.J.; Gulyás, L.; Schuster, S. (2000): Analysis of the MC1R sequence and its association to the coat color in the Hungarian coldblood. XXIX. Óvári Tudományos Napok. Poszter.
- Rieder, S.; Taourit, S.; Mariat, D.; Langlois, B.; Guérin, G. (2001): Mutations in the agouti (ASIP), the extension (MC1R), and the brown (TYRP1) loci and their association to coat color phenotypes in horses (Equus caballus). Mammalian Genome. 12. 450–455. https://doi.org/10.1007/s003350020017
- Saastamoinen, M.T.; Barrey, E. (2000): Genetics of conformation, locomotion and physiological traits. In: The genetics of the horse. Eds. Bowling, A.T.–Ruvinsky, A. CABI Publ., Wallingford, pp. 447, 452.
- Salisbury, G.W. (1941): The Inheritance of equine coat color, the basic color patterns. Journal of Heredity. 32. 235–241. https://doi.org/10.1093/oxfordjournals.jhered.a105049
- Searle, A.G. (1968): Comparative Genetics of Coat Colour in Mammals. Logos Press, London. 308 pp. ISBN: 978 0126334500
- Silvers, W.K. (1979): The coat color of mice, a model for mammalian gene action and interaction. Springer Verlag. New York ISBN: 978 0387903675
- Singleton, W.R.; Bond, Q.C. (1966): A allele necessary for dilute coat color in horses. Journal of Heredity. 57. 74–79. https://doi.org/10.1093/oxfordjournals.jhered.a107478
- Sponenberg, D.P.; Beaver, B.V. (1983): Horse Color. Texas A&M University Press, College Station ISBN: 978 0890961551
- Sponenberg, D.P.; Bowling, A.T. (1996): Champagne, a dominant colour dilution of horses. Genetics Selection Evolution. 28. 457–462. https://doi.org/10.1186/1297-9686-28-5-457
- Sponenberg, D.P. (1997): Genetics of colour and hair texture. In: Piper, L., Ruvinsky, A. (Eds.), The Genetics of Sheep. CABI Publishing, Wallingford, pp. 51–86.
- Sponenberg, D.P. (2003): Equine Color Genetics. Iowa State Univ. Press, Ames, USA. ISBN: 978 0813807591
- Sponenberg, D.P.; Bellone, R.R. (2017): Equine Color Genetics. 4th Edition Ames, IA: Iowa State University Press. ISBN: 978-1-119-13058-1.
- Stachurska, A.; Ussing, A.P.; Nestaas, T. (2001): Maści rozjaśnione na przykładzie koni fiordzkich. Med. Wet., 57(12): 876–879.
- Stachurska, A. (2002): Identyfikacja koni. Wyd. AR Lublin. ISBN: 83-7259-076-1
- Stachurska, A.; Brodacki, A. (2003): Polish Konik horse selection for coat colour and the ways to improve its effectiveness. Electronical Journal of Polish Agriculture University. Animal Husbandry. 6. 1.
- Stachurska, A.; Pięta, M.; Jaworski, Z.; Ussing, A..; Bruśniak, A.; Florek, M. (2004): Colour Variation in Blue Dun Polish Konik and Biłgoraj Horses. Livest. Prod. Sci., 90: 201–209. https://doi.org/10.1016/j.livprodsci.2004.04.002
- Stasiewicz, K.; Borkowska, M. (2007): Przewalski horse (Equus caballus przewalskii) – characteristics and conservation. University of Warmia and Mazury in Olsztyn. Polish Journal of Natural Sciences. 22, 1/2007, 43–49.
- Swinburne, J.; Gerstenberg, C.; Breen, M.; Aldridge, V.; Lockhart, L.; Marti, E.; Antczak, D.; Eggleston-Stott, M.; Baily, E.; Mickelson, J.; Roed, K.; Lindgren, G.; Von Haeringen, W.; Guerin, G.; Bjarnason, J.; Allen, T.; Binns, M. (2000): First comprehensive low-density horse linkage map based on two 3- generation, full-sibling, cross-bred horse reference families. Genomics. 66. 123–134. https://doi.org/10.1006/geno.2000.6207
- Swinburne, J.; Hopkins, A.; Binns, M. (2002): Assignment of the horse grey coat colour gene to ECA25 using the whole genome scanning. Animal Genetics. 33. 338–342. https://doi.org/10.1046/j.1365-2052.2002.00895.x
- Templeton, J.W.; Stewart, A.P.; Fletcher, W.S. (1977): Coat color genetics in the labrador retriever. Journal of Heredity. 68. 134–136. https://doi.org/10.1093/oxfordjournals.jhered.a108792
- Tóth, Zs.; Szőke, Sz.; Bodó, I.; Sölkner, J. (2004): Analysis of the grey colour intensity in horses. Debreceni Egyetem Agrártudományi Közlöny, Acta Agraria Debreceniensis, 14. University of Debrecen. Journal of Agricultural Science. 3–8. https://doi.org/10.34101/actaagrar/14/3360
- Tóth, Zs. (2005): Az egyes lószínek genetikai diverzitása. Debreceni Egyetem Agrártudományi Közlemények, 2005/16. különszám 40–45. https://doi.org/10.34101/actaagrar/16/3287
- Tóth, Zs.; Kaps, M.; Sölkner, J.; Bodo, I.; Curik, I. (2005): Quantitative genetic aspects of coat color in horses. Journal of Animal Science. https://doi.org/10.2527/jas.2005-704
- Turner, J.W.; Morrison, M.L. (2001): Influence of predation by mountain lions on numbers and survivorship of a feral horse population. Southwest. Nat., 46(2): 183–190. https://doi.org/10.2307/3672527
- Ussing, A.P. (2000): Hestenes farver. Nucleus Forlag ApS, Arhus, Denmark.
- Van Vleck, L.D.; Davitt, M. (1977): Confirmation of a gene for dominant dilution of horse colors. Journal of Heredity. 68. 280–282. p. https://doi.org/10.1093/oxfordjournals.jhered.a108836
- Wagner, J.K.; Jovel, C.; Norton, H.L.; Parra, E.J.; Shriver, M.D. (2002): Comparing quantitative measures of erythema, pigmentation and skin response using reflectometry. Pigment Cell Research. 15: 379–384. https://doi.org/10.1034/j.1600-0749.2002.02042.x
- Walther, R. (1912): Beiträge zur Kenntnis der Vererbung der Pferdefarben. Schaper Hannover, 9–219.
- Wilkins, A.S.; Wrangham, R.W.; Fitch, W.T. (2014): The “domestication syndrome” in mammals: A unified explanation based on neural crest cell behavior and genetics. Genetics, 197(3), 795–808. https://doi.org/10.1534/genetics.114.165423
- Zeder, M.A. (2012): The domestication of animals. Journal of Anthropological Research, 68(2), 161–190. https://doi.org/10.3998/jar.0521004.0068.201
- Zöldág, L. (2003): A kültakaró pigmentációs zavarainak genetikai alapjai háziállatokban. Magyar Állatorvosok Lapja. 9. 561–671.
- Zöldág, L.; Gáspárdy, A.; Eszes, F. (2003): A lószínekről az újabb genetikai ismeretek tükrében. Magyar Állatorvosok Lapja. 12. 707–720.
- Zöldág, L. (2004): A kültakaró színöröklődése háziállatokban 6. Színhígulások. Kistermelők Lapja. 9. 37. p.
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