title: Was skin cancer a selective force for black pigmentation in early hominin evolution?
abstract: Melanin provides a crucial filter for solar UV radiation and its genetically determined variation influences both skin pigmentation and risk of cancer. Genetic evidence suggests that the acquisition of a highly stable melanocortin 1 receptor allele promoting black pigmentation arose around the time of savannah colonization by hominins at some 1-2 Ma. The adaptive significance of dark skin is generally believed to be protection from UV damage but the pathologies that might have had a deleterious impact on survival and/or reproductive fitness, though much debated, are uncertain. Here, I suggest that data on age-associated cancer incidence and lethality in albinos living at low latitudes in both Africa and Central America support the contention that skin cancer could have provided a potent selective force for the emergence of black skin in early hominins.
authors.affiliation: Centre for Evolution and Cancer, Division of Molecular Pathology, Institute of Cancer Research, , Brookes Lawley Building, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK.
authors.forename: Mel
authors.initials: M
authors.lastname: Greaves
mesh_terms: D000417:Albinism / Q000503:physiopathology*; D000818:Animals; D005075:Biological Evolution; D015186:Hominidae / Q000235:genetics* / Q000502:physiology; D008543:Melanins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D044102:Receptor, Melanocortin, Type 1 / Q000235:genetics; D012641:Selection, Genetic; D012878:Skin Neoplasms / Q000235:genetics*; D012880:Skin Pigmentation / Q000235:genetics* / Q000502:physiology
chemical_list: D008543:Melanins; D044102:Receptor, Melanocortin, Type 1
keywords: UVB; albino; melanin; skin cancer