Flanagan N, Healy E, Ray A, Philips S, Todd C, Jackson I J, Birch-Machin M A, Rees J L
Department of Dermatology, University of Newcastle upon Tyne, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
Hum Mol Genet. 2000 Oct 12;9(17):2531-7. doi: 10.1093/hmg/9.17.2531.
Variants of the melanocortin 1 receptor (MC1R) gene are common in individuals with red hair and fair skin, but the relative contribution to these pigmentary traits in heterozygotes, homozygotes and compound heterozygotes for variants at this locus from the multiple alleles present in Caucasian populations is unclear. We have investigated 174 individuals from 11 large kindreds with a preponderance of red hair and an additional 99 unrelated redheads, for MC1R variants and have confirmed that red hair is usually inherited as a recessive characteristic with the R151C, R160W, D294H, R142H, 86insA and 537insC alleles at this locus. The V60L variant, which is common in the population may act as a partially penetrant recessive allele. These individuals plus 167 randomly ascertained Caucasians demonstrate that heterozygotes for two alleles, R151C and 537insC, have a significantly elevated risk of red hair. The shade of red hair frequently differs in heterozygotes from that in homozygotes/compound heterozygotes and there is also evidence for a heterozygote effect on beard hair colour, skin type and freckling. The data provide evidence for a dosage effect of MC1R variants on hair as well as skin colour.
黑皮质素1受体（MC1R）基因的变异在红头发和皮肤白皙的个体中很常见，但在白种人群体中，该基因座上多个等位基因的杂合子、纯合子和复合杂合子对这些色素性状的相对贡献尚不清楚。我们调查了来自11个大型家族的174名个体，这些家族中红头发者居多，另外还调查了99名无亲缘关系的红头发个体，检测他们的MC1R变异情况，证实红头发通常作为一种隐性特征遗传，该基因座上的R151C、R160W、D294H、R142H、86insA和537insC等位基因与之相关。人群中常见的V60L变异可能作为一种部分显性的隐性等位基因起作用。这些个体加上167名随机确定的白种人表明，R151C和537insC这两个等位基因的杂合子出现红头发的风险显著升高。杂合子的红头发色泽通常与纯合子/复合杂合子不同，并且有证据表明杂合子对胡须颜色、皮肤类型和雀斑有影响。这些数据为MC1R变异对头发和肤色的剂量效应提供了证据。
