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Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Human pigmentation variation: evolution, genetic basis, and implications for public health
1Department of Anthropology, University of Toronto at Mississauga, Mississauga, ON, Canada L5L 1C6. esteban.parra@utoronto.ca
American Journal of Physical Anthropology
|November 30, 2007
Summary
Human skin pigmentation diversity is shaped by natural selection, not just genetics. Recent studies identify key genes, revealing complex evolutionary patterns and the mosaic nature of human genetic variation.
Area of Science:
- Human genetics
- Evolutionary biology
- Population genetics
Background:
- Human pigmentation exhibits significant diversity across populations, contrasting with the low genetic variation between continental groups.
- This discrepancy is primarily attributed to natural selection acting on pigmentation traits along a latitudinal gradient.
Purpose of the Study:
- To explore the genetic underpinnings of human pigmentation diversity.
- To understand the evolutionary history and selective pressures shaping pigmentation traits.
- To highlight the importance of studying pigmentation for interpreting human genetic variation and public health.
Main Methods:
- Genotype/phenotype association studies.
- Direct functional assays.
- Analysis of recent research (last 5 years) on pigmentation genes.
Main Results:
- Identification of at least six genes involved in human pigmentation.
- Evidence of positive selection acting on different genomic locations and population groups.
- Demonstration of the complex genetic architecture underlying pigmentation.
Conclusions:
- Human genetic variation is mosaic, with different genomic regions having distinct evolutionary histories.
- Pigmentation serves as a model for understanding complex traits and gene-gene interactions.
- Understanding pigmentation genetics is crucial for public health, particularly regarding skin cancer risk and vitamin D synthesis.
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