title: Ultraviolet radiation represents an evolutionary selective pressure for the south-to-north gradient of the MTHFR 677TT genotype.
authors.forename: Loren
authors.initials: L
authors.lastname: Cordain
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Hickey
mesh_terms: D005786:Gene Expression Regulation; D005838:Genotype; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D012880:Skin Pigmentation / Q000502:physiology*; D013472:Sunlight; D014466:Ultraviolet Rays; D014805:Vitamin B 12 / Q000097:blood*
chemical_list: D042965:Methylenetetrahydrofolate Reductase (NADPH2); D014805:Vitamin B 12