OCA2
P protein is a protein that in humans is encoded by the OCA2 gene.[1]
OCA2 encodes the human homologue of the mouse p (pink-eyed dilution) gene. The P protein is believed to be an integral membrane protein involved in small molecule transport, specifically tyrosine - a precursor of melanin. Certain mutations in OCA2 result in type 2 oculocutaneous albinism.[1]
A mutation in the HERC2 gene adjacent to OCA2, affecting OCA2's expression in the human iris, is found common to nearly all people with blue eyes. It has been hypothesized that all blue eyed humans share a single common ancestor with whom the mutation originated.[2][3][4]
A study has found the His615Arg allele of OCA2 is involved in the light skin tone in people of East Asian descent.[5]
References
- ^ a b "Entrez Gene: OCA2 oculocutaneous albinism II (pink-eye dilution homolog, mouse)". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=4948.
- ^ Bryner J (2008-01-31). "Here's what made those brown eyes blue". Health News. MSNBC. http://www.msnbc.msn.com/id/22934464/wid/11915773?GT1=10815#storyContinued. Retrieved 2008-11-06. ; Bryner J (2008-01-31). "One Common Ancestor Behind Blue Eyes". LiveScience. Imaginova Corp.. http://www.livescience.com/health/080131-blue-eyes.html. Retrieved 2008-11-06. ; "Blue-eyed humans have a single, common ancestor". News. University of Copenhagen. 2008-01-30. http://www.ku.dk/english/news/?content=http://www.ku.dk/english/news/blue-eyes.htm. Retrieved 2008-11-06.
- ^ Eiberg H, Troelsen J, Nielsen M, Mikkelsen A, Mengel-From J, Kjaer KW, Hansen L (March 2008). "Blue eye color in humans may be caused by a perfectly associated founder mutation in a regulatory element located within the HERC2 gene inhibiting OCA2 expression". Human genetics 123 (2): 177–87. doi:10.1007/s00439-007-0460-x. PMID 18172690.
- ^ Sturm RA, Duffy DL, Zhao ZZ, Leite FP, Stark MS, Hayward NK, Martin NG, Montgomery GW (February 2008). "A Single SNP in an Evolutionary Conserved Region within Intron 86 of the HERC2 Gene Determines Human Blue-Brown Eye Color". American journal of human genetics 82 (2): 424–31. doi:10.1016/j.ajhg.2007.11.005. PMC 2427173. PMID 18252222. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2427173.
- ^ Edwards M, Bigham A, Tan J, Li S, Gozdzik A, Ross K, Jin L, Parra EJ (2010). McVean, Gil. ed. "Association of the OCA2 Polymorphism His615Arg with Melanin Content in East Asian Populations: Further Evidence of Convergent Evolution of Skin Pigmentation". PLoS Genet. 6 (3): e1000867. doi:10.1371/journal.pgen.1000867. PMC 2832666. PMID 20221248. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2832666.
External links
Further reading
- Oetting WS, King RA (1999). "Molecular basis of albinism: mutations and polymorphisms of pigmentation genes associated with albinism". Hum. Mutat. 13 (2): 99–115. doi:10.1002/(SICI)1098-1004(1999)13:2<99::AID-HUMU2>3.0.CO;2-C. PMID 10094567.
- Brilliant MH (2001). "The mouse p (pink-eyed dilution) and human P genes, oculocutaneous albinism type 2 (OCA2), and melanosomal pH". Pigment Cell Res. 14 (2): 86–93. doi:10.1034/j.1600-0749.2001.140203.x. PMID 11310796.
- Ramsay M, Colman MA, Stevens G et al. (1992). "The tyrosinase-positive oculocutaneous albinism locus maps to chromosome 15q11.2-q12". Am. J. Hum. Genet. 51 (4): 879–84. PMC 1682821. PMID 1415228. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1682821.
- Gardner JM, Nakatsu Y, Gondo Y et al. (1992). "The mouse pink-eyed dilution gene: association with human Prader-Willi and Angelman syndromes". Science 257 (5073): 1121–4. doi:10.1126/science.257.5073.1121. PMID 1509264.
- Ludowese CJ, Thompson KJ, Sekhon GS, Pauli RM (1992). "Absence of predictable phenotypic expression in proximal 15q duplications". Clin. Genet. 40 (3): 194–201. doi:10.1111/j.1399-0004.1991.tb03076.x. PMID 1773534.
- Lee ST, Nicholls RD, Jong MT et al. (1995). "Organization and sequence of the human P gene and identification of a new family of transport proteins". Genomics 26 (2): 354–63. doi:10.1016/0888-7543(95)80220-G. PMID 7601462.
- Spritz RA, Fukai K, Holmes SA, Luande J (1995). "Frequent intragenic deletion of the P gene in Tanzanian patients with type II oculocutaneous albinism (OCA2)". Am. J. Hum. Genet. 56 (6): 1320–3. PMC 1801108. PMID 7762554. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1801108.
- Lee ST, Nicholls RD, Schnur RE et al. (1995). "Diverse mutations of the P gene among African-Americans with type II (tyrosinase-positive) oculocutaneous albinism (OCA2)". Hum. Mol. Genet. 3 (11): 2047–51. PMID 7874125.
- Durham-Pierre D, Gardner JM, Nakatsu Y et al. (1994). "African origin of an intragenic deletion of the human P gene in tyrosinase positive oculocutaneous albinism". Nat. Genet. 7 (2): 176–9. doi:10.1038/ng0694-176. PMID 7920637.
- Lee ST, Nicholls RD, Bundey S et al. (1994). "Mutations of the P gene in oculocutaneous albinism, ocular albinism, and Prader-Willi syndrome plus albinism". N. Engl. J. Med. 330 (8): 529–34. doi:10.1056/NEJM199402243300803. PMID 8302318.
- Rinchik EM, Bultman SJ, Horsthemke B et al. (1993). "A gene for the mouse pink-eyed dilution locus and for human type II oculocutaneous albinism". Nature 361 (6407): 72–6. doi:10.1038/361072a0. PMID 8421497.
- Spritz RA, Lee ST, Fukai K et al. (1997). "Novel mutations of the P gene in type II oculocutaneous albinism (OCA2)". Hum. Mutat. 10 (2): 175–7. doi:10.1002/(SICI)1098-1004(1997)10:2<175::AID-HUMU12>3.0.CO;2-X. PMID 9259203.
- Kerr R, Stevens G, Manga P et al. (2000). "Identification of P gene mutations in individuals with oculocutaneous albinism in sub-Saharan Africa". Hum. Mutat. 15 (2): 166–72. doi:10.1002/(SICI)1098-1004(200002)15:2<166::AID-HUMU5>3.0.CO;2-Z. PMID 10649493.
- Oetting WS, Gardner JM, Fryer JP et al. (2000). "Mutations of the human P gene associated with Type II oculocutaneous albinism (OCA2). Mutations in brief no. 205. Online". Hum. Mutat. 12 (6): 434. doi:10.1002/(SICI)1098-1004(1998)12:6<434::AID-HUMU16>3.0.CO;2-7. PMID 10671067.
- Passmore LA, Kaesmann-Kellner B, Weber BH (2000). "Novel and recurrent mutations in the tyrosinase gene and the P gene in the German albino population". Hum. Genet. 105 (3): 200–10. doi:10.1007/s004390051090. PMID 10987646.
- Manga P, Kromberg J, Turner A et al. (2001). "In Southern Africa, Brown Oculocutaneous Albinism (BOCA) Maps to the OCA2 Locus on Chromosome 15q: P-Gene Mutations Identified". Am. J. Hum. Genet. 68 (3): 782–7. doi:10.1086/318800. PMC 1274491. PMID 11179026. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1274491.
- Manga P, Orlow SJ (2002). "Inverse correlation between pink-eyed dilution protein expression and induction of melanogenesis by bafilomycin A1". Pigment Cell Res. 14 (5): 362–7. doi:10.1034/j.1600-0749.2001.140508.x. PMID 11601658.
- Toyofuku K, Valencia JC, Kushimoto T et al. (2002). "The etiology of oculocutaneous albinism (OCA) type II: the pink protein modulates the processing and transport of tyrosinase". Pigment Cell Res. 15 (3): 217–24. doi:10.1034/j.1600-0749.2002.02007.x. PMID 12028586.