Department of Pathology, Penn State College of Medicine, Hershey, United States.
Jake Gittlen Laboratories for Cancer Research, Penn State College of Medicine, Hershey, United States.
Elife. 2023 Jun 9;12:e77514. doi: 10.7554/eLife.77514.
Our interest in the genetic basis of skin color variation between populations led us to seek a Native American population with genetically African admixture but low frequency of European light skin alleles. Analysis of 458 genomes from individuals residing in the Kalinago Territory of the Commonwealth of Dominica showed approximately 55% Native American, 32% African, and 12% European genetic ancestry, the highest Native American genetic ancestry among Caribbean populations to date. Skin pigmentation ranged from 20 to 80 melanin units, averaging 46. Three albino individuals were determined to be homozygous for a causative multi-nucleotide polymorphism contained within a haplotype of African origin; its allele frequency was 0.03 and single allele effect size was -8 melanin units. Derived allele frequencies of and were 0.14 and 0.06, with single allele effect sizes of -6 and -4, respectively. Native American genetic ancestry by itself reduced pigmentation by more than 20 melanin units (range 24-29). The responsible hypopigmenting genetic variants remain to be identified, since none of the published polymorphisms predicted in prior literature to affect skin color in Native Americans caused detectable hypopigmentation in the Kalinago.
我们对人群间皮肤颜色变化的遗传基础很感兴趣，因此我们寻找了一个具有遗传上的非洲混合血统但欧洲浅色皮肤等位基因频率较低的美洲原住民群体。对居住在多米尼克联邦卡利纳戈地区的 458 个人的基因组进行分析表明，他们的遗传背景中约有 55%是美洲原住民，32%是非洲人，12%是欧洲人，这是迄今为止加勒比人群体中美洲原住民遗传背景比例最高的一次。皮肤色素沉着范围从 20 到 80 个黑色素单位，平均为 46。三个白化病个体被确定为一个多核苷酸突变的纯合子，该突变位于一个源自非洲的单倍型内；其等位基因频率为 0.03，单等位基因效应大小为-8 个黑色素单位。 和 的衍生等位基因频率分别为 0.14 和 0.06，单等位基因效应大小分别为-6 和-4。仅美洲原住民的遗传背景就使色素沉着减少了 20 多个黑色素单位（范围 24-29）。由于在先前的文献中预测会影响美洲原住民肤色的已发表的多态性中没有一个导致卡利纳戈人出现可检测到的色素减退，因此仍需确定导致这种色素减退的遗传变异体。
