A Genome-Wide Association Study Identifies the Skin Color Genes IRF4, MC1R, ASIP, and BNC2 Influencing Facial Pigmented Spots

J Invest Dermatol. 2015 Jul;135(7):1735-1742. doi: 10.1038/jid.2015.62. Epub 2015 Feb 23.

Abstract

Facial pigmented spots are a common skin aging feature, but genetic predisposition has yet to be thoroughly investigated. We conducted a genome-wide association study for pigmented spots in 2,844 Dutch Europeans from the Rotterdam Study (mean age: 66.9±8.0 years; 47% male). Using semi-automated image analysis of high-resolution digital facial photographs, facial pigmented spots were quantified as the percentage of affected skin area (mean women: 2.0% ±0.9, men: 0.9% ±0.6). We identified genome-wide significant association with pigmented spots at three genetic loci: IRF4 (rs12203592, P=1.8 × 10(-27)), MC1R (compound heterozygosity score, P=2.3 × 10(-24)), and RALY/ASIP (rs6059655, P=1.9 × 10(-9)). In addition, after adjustment for the other three top-associated loci the BNC2 locus demonstrated significant association (rs62543565, P=2.3 × 10(-8)). The association signals observed at all four loci were successfully replicated (P<0.05) in an independent Dutch cohort (Leiden Longevity Study n=599). Although the four genes have previously been associated with skin color variation and skin cancer risk, all association signals remained highly significant (P<2 × 10(-8)) when conditioning the association analyses on skin color. We conclude that genetic variations in IRF4, MC1R, RALY/ASIP, and BNC2 contribute to the acquired amount of facial pigmented spots during aging, through pathways independent of the basal melanin production.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agouti Signaling Protein / genetics*
  • Cohort Studies
  • DNA-Binding Proteins / genetics*
  • Facial Dermatoses / genetics
  • Female
  • Genetic Predisposition to Disease / epidemiology*
  • Genome-Wide Association Study
  • Humans
  • Interferon Regulatory Factors / genetics*
  • Male
  • Melanosis / genetics
  • Middle Aged
  • Netherlands
  • Nevus, Pigmented / genetics
  • Phenotype
  • Photography
  • Prospective Studies
  • Receptor, Melanocortin, Type 1 / genetics*
  • Sensitivity and Specificity
  • Skin Neoplasms / genetics
  • Skin Pigmentation / genetics*

Substances

  • ASIP protein, human
  • Agouti Signaling Protein
  • BNC2 protein, human
  • DNA-Binding Proteins
  • Interferon Regulatory Factors
  • Receptor, Melanocortin, Type 1
  • interferon regulatory factor-4