--- license: permission_granted topic_id: companion_breed_health_shetland_pony_horse_chestnut_horse category: companion-breed-health title: "Shetland Pony (Horse) — Chestnut (hereditary; OMIA-verified breed predisposition)" lang: en source: "OMIA (Online Mendelian Inheritance in Animals, University of Sydney) breed-specific hereditary-disorder record, saved verbatim to source_file; C1 substring-verified. Pulled 2026-08-23 from local OMIA database dump." source_file: pdf-raw/breed-health/shetland_pony_horse_chestnut_2256.txt date_parsed: 2026-08-23 tokens_estimated: 113 verification: method: substring_match claims: 5 passed: 5 date: 2026-08-23 recovered: false path: companion-breed-health/companion_breed_health_shetland_pony_horse_chestnut_horse/01_companion_breed_health_shetland_pony_horse_chestnut_horse.md source_document: "OMIA — Online Mendelian Inheritance in Animals (University of Sydney)" citation: authority: "OMIA — Online Mendelian Inheritance in Animals (University of Sydney)" title: "Shetland Pony (Horse) — Chestnut (hereditary; OMIA-verified breed predisposition)" url: "https://omia.org/OMIA001199/9796/" retrieved: "2026-08-23" ref: "OMIA breed-specific hereditary-disorder records (omia.org), derived from local OMIA database dump; dataset: https://doi.org/10.25910/2AMR-PV70" doc_type: "academic animal-genetics database (breed-specific disorder entries)" needs_review: false
verification_derived: method: derived_from_dataset source: "OMIA database dump (omia.xml, local); fields Gene/Variant/Article/OMIM" note: "Structured fields (gene, variant rsID/protein change, PubMed/DOI references, OMIM cross-link) extracted from OMIA dump and presented with first-hand values; not verbatim prose."---
Shetland Pony (Horse) — Chestnut (hereditary; OMIA-verified breed predisposition)
Source: first-hand OMIA (University of Sydney) breed-specific hereditary-disorder record, saved verbatim to source_file; every claim below is a C1 byte-substring of it.
Claims
Breed: Shetland Pony (Horse)Disorder: ChestnutMode of inheritance: AutosomalSummary: Various theories on the inheritance of horse coat colours have existed for many decades. Since the 1990s, the full force of molecular biology has been brought to bear on this topic. The first results of such work in horses were reported by Marklund et al. (1996) (see below).Defect: no
Associated gene(s)
Derived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.
- Gene: MSH-R (Entrez Gene ID 4211893) — OMIA Phene_Gene / GeneSynonym
- OMIA molecular-genetics note: By cloning and sequencing a very likely comparative candidate gene (based on the very reasonable assumption that chestnut coat colour in horses is due to an allele at the extension locus), Marklund et al. (1996) showed that chestnut coat colour in 12 different breeds is due to a missense mutation in the gene for melanocyte-stimulating hormone receptor (MSHR or MC1R).
Evidence (references)
Derived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.
- 1982. A linkage group composed of 3 coat colour genes and 3 serum protein loci in horses. Journal of Heredity — PubMed:PMID7096983 — OMIA Phene_Article / Article
- 1994. Parentage Testing and Linkage Analysis in the Horse Using a Set of Highly Polymorphic Microsatellites. Animal Genetics — PubMed:PMID8161016 — OMIA Phene_Article / Article
- 1996. The equine MSH-R TaqI RFLP is not informative for hair colour in Arabian horses. Animal Genetics — PubMed:PMID8624048 — OMIA Phene_Article / Article
- 1996. A missense mutation in the gene for melanocyte-stimulating hormone receptor (MC1R) is associated with the chestnut coat color in horses. Mammalian Genome — PubMed:PMID8995760 — OMIA Phene_Article / Article
- 1997. Dominant black in horses. Genetics Selection Evolution — OMIA Phene_Article / Article
- 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 — PubMed:PMID11353392 | DOI:10.1007/s003350020017 — OMIA Phene_Article / Article
- 2001. Analysis of the genetic structure of the breeding nucleus of the Russian population of thoroughbred horses by the extension locus molecular DNA typing. Russian Journal of Genetics — OMIA Phene_Article / Article
- 2002. Horse breeding: genetic tests for the coat colors chestnut, bay and black. Results from a first study in the Swiss Franches-Montagnes horse breed. Schweiz Arch Tierheilkd — PubMed:PMID12224446 | DOI:10.1024/0036-7281.144.8.405 — OMIA Phene_Article / Article
- 2003. Melanocortin receptor variants with phenotypic effects in horse, pig, and chicken. Annals of the New York Academy of Sciences — PubMed:PMID12851331 — OMIA Phene_Article / Article
- 2008. Technical note: a novel method for routine genotyping of horse coat color gene polymorphisms. J Anim Sci — PubMed:PMID18310485 | DOI:10.2527/jas.2007-0498 — OMIA Phene_Article / Article
- 2009. Identification of horse chestnut coat color genotype using SNaPshot. BMC Res Notes — PubMed:PMID20015355 | DOI:10.1186/1756-0500-2-255 — OMIA Phene_Article / Article
- 2009. Development of a method for simultaneously genotyping multiple horse coat colour loci and genetic investigation of basic colour variation in Thoroughbred and Misaki horses in Japan. J Anim Breed Genet — PubMed:PMID19912416 | DOI:10.1111/j.1439-0388.2009.00841.x — OMIA Phene_Article / Article
- (28 additional references in OMIA)
Comparative medicine (human OMIM)
Derived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.
- OMIM:266300 (type: trait) — OMIA Group_OMIM (via OMIA_ID)
- OMIM:155555 (type: gene) — OMIA Group_OMIM (via OMIA_ID)