title: Association of melanogenesis genes with skin color variation among Japanese females.
abstract: BACKGROUND
  Skin color mainly reflects pigmentation resulting from melanin. Although many of the detailed molecular mechanisms involved in melanin pigmentation are being revealed, little is understood about the genetic components responsible for variations in skin color within or between human populations.
  
  
  OBJECTIVE
  To investigate the contribution of the melanogenesis genes to skin color variation in Japanese population.
  
  
  METHODS
  We examined the association between 12 variants of four pigmentation-related genes (TYR, OCA2, SLC45A2, MC1R) and variations in the melanin index of 456 Japanese females using a multiple regression analysis.
  
  
  RESULTS
  OCA2 A481T (p=6.18×10(-8)) and, OCA2 H615R (p=5.72×10(-6)) were strongly associated with the melanin index. In addition, our results yielded evidence for a significant association in a combined analysis of males and females (OCA2 A481T p=2.1×10(-11), and OCA2 H615R p=1.0×10(-7)). Then five surviving variants including A481T, H615R, T387M in OCA2, D125Y in TYR, and T500P in SLC45A2, accounted for contribution to about 11% of the melanin index.
  
  
  CONCLUSIONS
  The skin color analysis among Japanese was successfully carried out to determine the association with genetic components by using the melanin index as an objective indicator. We believe that a better understanding of the genetic basis of skin color variation will be valuable for elucidating the correlation of pigmentation phenotype with skin-cancer risk.
authors.affiliation: Department of Dermatology, Yamagata University Faculty of Medicine, Yamagata 990-9585, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Abe
authors.forename: Gen
authors.initials: G
authors.lastname: Tamiya
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nakamura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Hozumi
authors.forename: Tamio
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D000328:Adult; D000368:Aged; D054366:Agouti Signaling Protein / Q000235:genetics; D000951:Antigens, Neoplasm / Q000235:genetics*; D044466:Asian People / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D008543:Melanins / Q000235:genetics; D026901:Membrane Transport Proteins / Q000235:genetics*; D008875:Middle Aged; D014442:Monophenol Monooxygenase / Q000235:genetics*; D044102:Receptor, Melanocortin, Type 1 / Q000235:genetics*; D012044:Regression Analysis; D012880:Skin Pigmentation / Q000235:genetics*; D055815:Young Adult
chemical_list: C515182:ASIP protein, human; D054366:Agouti Signaling Protein; D000951:Antigens, Neoplasm; D008543:Melanins; D026901:Membrane Transport Proteins; C489600:OCA2 protein, human; D044102:Receptor, Melanocortin, Type 1; C510061:SLC45A2 protein, human; D014442:Monophenol Monooxygenase