
<ArticleTitle>Interaction between the <prot>melanocortin-1 receptor</prot> and <prot>P gene</prot>s contributes to inter-individual variation in skin pigmentation phenotypes in a Tibetan population.</ArticleTitle>
<AbstractText>The <prot>melanocortin-1 receptor</prot> (<prot>MC1R</prot>) and <prot>P gene</prot> product are two important components of the human pigmentary system that have been shown to be associated with red hair/fair skin and cause type II oculocutaneous albinism, respectively. However, their contribution to inter-individual variation at the population level is not well defined. To this end, we genotyped 3 single nucleotide polymorphisms (SNPs) in the <prot>MC1R</prot> gene (Arg67Gln, Gln163Arg, Val92Met) and 2 SNPs in the <prot>P gene</prot> (IVS 13-15 and Gly780Gly) in 184 randomly ascertained Tibetan subjects, whose skin color was measured as a quantitative trait by reflective spectroscopy. Single locus analyses failed to demonstrate an association between any of the 5 SNPs and skin pigmentation. However, when an epistatic model was applied to the data, a significant gene-gene interaction was identified between Val92Met in <prot>MCIR</prot> and IVS13-15 in the <prot>P gene</prot> (F=2.43; P=0.0105). We also discuss the possible mechanisms of how gene interactions arise in signal transduction pathways.</AbstractText>
