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Updated: Jul 30, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
High polymorphism at the human melanocortin 1 receptor locus
B K Rana1, D Hewett-Emmett, L Jin
1Human Genetics Center, School of Public Health and Graduate School of Biomedical Sciences, University of Texas, Houston, Texas 77030, USA.
Genetics
|April 2, 1999
Summary
Human skin and hair color variation is linked to the melanocortin 1 receptor (MC1R) gene. Specific MC1R variants, like Arg163Gln, show high frequency in East/Southeast Asians, influencing pigmentation evolution.
Area of Science:
- Genetics
- Human Evolution
- Molecular Biology
Background:
- Human pigmentation diversity arises from varying eumelanin and phaeomelanin levels.
- The melanocortin 1 receptor (MC1R) gene regulates melanin production, with known mutations affecting coat color in mammals.
Purpose of the Study:
- To investigate genetic variations in the human MC1R gene across global populations, with a focus on Asian populations.
- To explore the evolutionary history of the MC1R gene in humans and other primates.
Main Methods:
- Sequencing of the MC1R gene in 121 individuals from diverse world populations.
- Comparative sequencing of the MC1R gene in chimpanzees, gorillas, orangutans, and baboons.
Main Results:
- Identified five nonsynonymous variants (Arg67Gln, Asp84Glu, Val92Met, Arg151Cys, Arg163Gln) and one synonymous variant (A942G) in the human MC1R gene.
- The Arg163Gln variant is highly prevalent (70%) in East and Southeast Asian populations, but rare in African and European populations.
- Human MC1R shows rapid evolution compared to other melanocortin receptor family genes, with higher nucleotide diversity possibly due to selection.
Conclusions:
- MC1R genetic variation significantly contributes to human pigmentation differences, particularly in Asian populations.
- The MC1R gene has undergone rapid evolutionary changes, suggesting adaptive selection related to pigmentation.
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