OMIA:001199-61406 : Coat colour, extension in Leopardus colocolo (Colocolo)
In other species: lorises , coyote , dog , red fox , American black bear , domestic cat , jaguar , ass (donkey) , horse , Przewalski's horse , pig , Arabian camel , reindeer , taurine cattle , indicine cattle (zebu) , goat , sheep , rabbit , Mongolian gerbil , domestic guinea pig , domestic yak , fallow deer , alpaca , gray squirrel , raccoon dog , antarctic fur seal , woolly mammoth , rock pocket mouse , oldfield mouse , lesser earless lizard , Geoffroy's cat , jaguarundi , little striped whiptail , water buffalo , Arctic fox
Categories: Pigmentation phene
Links to MONDO diseases: No links.
Mendelian trait/disorder: yes
Considered a defect: no
Key variant known: no
Cross-species summary: The extension locus encodes the melanocyte-stimulating hormone receptor (MSHR; now known as MC1R). This receptor controls the level of tyrosinase within melanocytes. Tyrosinase is the limiting enzyme involved in synthesis of melanins: high levels of tyrosinase result in the production of eumelanin (dark colour, e.g. brown or black), while low levels result in the production of phaeomelanin (light colour, e.g. red or yellow). When melanocyte-stimulating hormone (MSH) binds to its receptor, the level of tyrosinase is increased, leading to production of eumelanin. The wild-type allele at the extension locus corresponds to a functional MSHR, and hence to dark pigmentation in the presence of MSH. As explained by Schneider et al. (PLoS Genet 10(2): e1004892; 2015), "The most common causes of melanism (black coat) mutations are gain-of-function alterations in MC1R, or loss-of function alterations in ASIP, which encodes Agouti signaling protein, a paracrine signaling molecule that inhibits MC1R signaling". Mutations in MC1R have been associated with white colouring in several species.
Have human generated variants been created, e.g. through genetic engineering and gene editing
Cite this entry
|2015||Schneider, A., Henegar, C., Day, K., Absher, D., Napolitano, C., Silveira, L., David, V.A., O'Brien, S.J., Menotti-Raymond, M., Barsh, G.S., Eizirik, E. :|
|Recurrent evolution of melanism in South American felids. PLoS Genet 11:e1004892, 2015. Pubmed reference: 25695801. DOI: 10.1371/journal.pgen.1004892.|
- Created by Frank Nicholas on 26 Apr 2016