Hajjej Abdelhafidh, Almawi Wassim Y, Hattab Lasmar, Hmida Slama
Department of Immunogenetics, National Blood Transfusion Center, Tunis, Tunisia.
Department of Medical Biochemistry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama, Bahrain.
Immunol Lett. 2017 May;185:12-26. doi: 10.1016/j.imlet.2017.02.014. Epub 2017 Mar 6.
Despite their importance, anthropological meta-analyses which allow for comprehensive evaluation of the relationships of a given population were rare. This meta-analysis evaluates the origin of Tunisians using polymorphic profile of HLA class I (A, B), and class II (DRB1, DQB1) genes, in historical, social and cultural context, and is the only analysis in the Middle East-North Africa (MENA) region. A total of 20 eligible populations were selected from several databases, and included representing 2553 Tunisian individuals, who were compared with Mediterranean and sub-Saharan populations. In total, 204 HLA alleles were detected in Tunisians, which comprised 54 HLA-A, 76 HLA-B, 50 DRB1, and 24 DQB1 alleles. The most frequent alleles were A02:01(24.72%) in Berbers of Zrawa, B50:01 (13.90.11%) in Tunisian-So, DRB107:01 (28.66%) in Ghannouchians, and DQB102:01 (42.79%) in Tunisians-H. The A, B, DRB, and DQB1 genotypes of 420 individuals were further subjected to a selection study. Despite the relatively large sample size, the loci depicted non-significant negative Fnd values, an indication of overall trend to balancing selection or gene flow. Except for Berbers of Djerba, dendrograms, correspondence analyses, genetic distances and haplotype analysis demonstrated the close relatedness of Berbers, Southern and Northern Tunisians, and strong relatedness was evident to Western Mediterranean, North African and Iberian populations, but not Sub-Saharans and Eastern Mediterranean populations, including Arabs. Collectively, this suggests that the contribution of Arabs and sub-Saharans to the present Tunisian gene pool is low. In addition, all Mediterranean populations depict a typical Mediterranean substratum, except for Greeks.
尽管其很重要，但能够全面评估特定人群关系的人类学荟萃分析却很少见。本荟萃分析在历史、社会和文化背景下，利用人类白细胞抗原I类（A、B）和II类（DRB1、DQB1）基因的多态性概况评估突尼斯人的起源，这是中东和北非（MENA）地区唯一的此类分析。从几个数据库中总共选取了20个符合条件的人群，包括代表2553名突尼斯个体的样本，将其与地中海和撒哈拉以南人群进行比较。在突尼斯人中总共检测到204个HLA等位基因，其中包括54个HLA - A、76个HLA - B、50个DRB1和24个DQB1等位基因。最常见的等位基因分别是：兹拉瓦柏柏尔人中的A02:01（24.72%）、突尼斯索人中的B50:01（13.90.11%）、加努奇人中的DRB107:01（28.66%）以及突尼斯H人群中的DQB102:01（42.79%）。对420名个体的A、B、DRB和DQB1基因型进一步进行了选择研究。尽管样本量相对较大，但这些基因座显示出不显著的负Fnd值，这表明存在平衡选择或基因流动的总体趋势。除了杰尔巴岛的柏柏尔人外，聚类图、对应分析、遗传距离和单倍型分析表明，柏柏尔人、突尼斯南部和北部人群关系密切，与西地中海、北非和伊比利亚人群有很强的相关性，但与撒哈拉以南和东地中海人群（包括阿拉伯人）没有明显相关性。总体而言，这表明阿拉伯人和撒哈拉以南人群对当前突尼斯基因库的贡献较低。此外，除了希腊人之外，所有地中海人群都呈现出典型的地中海基因底层特征。
