OPRM1 and EGFR Contribute to Skin Pigmentation Differences Between Indigenous Americans and Europeans

Hum Genet. 2012 Jul;131(7):1073-80. doi: 10.1007/s00439-011-1135-1. Epub 2011 Dec 24.

Abstract

Contemporary variation in skin pigmentation is the result of hundreds of thousands years of human evolution in new and changing environments. Previous studies have identified several genes involved in skin pigmentation differences among African, Asian, and European populations. However, none have examined skin pigmentation variation among Indigenous American populations, creating a critical gap in our understanding of skin pigmentation variation. This study investigates signatures of selection at 76 pigmentation candidate genes that may contribute to skin pigmentation differences between Indigenous Americans and Europeans. Analysis was performed on two samples of Indigenous Americans genotyped on genome-wide SNP arrays. Using four tests for natural selection--locus-specific branch length (LSBL), ratio of heterozygosities (lnRH), Tajima's D difference, and extended haplotype homozygosity (EHH)--we identified 14 selection-nominated candidate genes (SNCGs). SNPs in each of the SNCGs were tested for association with skin pigmentation in 515 admixed Indigenous American and European individuals from regions of the Americas with high ground-level ultraviolet radiation. In addition to SLC24A5 and SLC45A2, genes previously associated with European/non-European differences in skin pigmentation, OPRM1 and EGFR were associated with variation in skin pigmentation in New World populations for the first time.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Neoplasm / genetics
  • Antiporters / genetics
  • ErbB Receptors / genetics*
  • European Continental Ancestry Group / genetics*
  • Genetic Testing / methods
  • Genotype
  • Haplotypes
  • Humans
  • Indians, North American / genetics*
  • Membrane Transport Proteins / genetics
  • Polymorphism, Single Nucleotide
  • Receptors, Opioid, mu / genetics*
  • Skin Pigmentation / genetics*

Substances

  • Antigens, Neoplasm
  • Antiporters
  • Membrane Transport Proteins
  • OPRM1 protein, human
  • Receptors, Opioid, mu
  • SLC24A5 protein, human
  • SLC45A2 protein, human
  • EGFR protein, human
  • ErbB Receptors