Arends A, Alvarez M, Velázquez D, Bravo M, Salazar R, Guevara J M, Castillo O
Laboratorio de Hemoglobinas Anormales, Servicio de Hematología "Dr. Tulio Arends" Hospital Universitario de Caracas, Caracas, Venezuela.
Am J Hematol. 2000 Jun;64(2):87-90. doi: 10.1002/(sici)1096-8652(200006)64:2<87::aid-ajh2>3.0.co;2-b.
Sickle cell anemia and alpha-thalassemia have a heterogeneous distribution in Venezuela with a high frequency in the coastal area (sea level) and few cases in the mountains. Most of our population is an ethnic admixture of Europeans (Spaniards colonists), Africans (slaves), and Amerindians. The purpose of our study was to determine the origin of the beta(s) globin haplotype, age and survival dependency, and the admixture among the different African groups in our population. The alpha(3.7) globin gene deletion status was also studied and found in a very high frequency. DNA from peripheral blood of 191 non-related patients (81 with HbS homozygous and 15 patients compound heterozygous for HbS, HbC, HbD with beta-thalassemia, and 95 with sickle cell trait) were studied. The beta(s) chromosome was linked 51% to the Benin Haplotype, 29.5% with the CAR, 12.5% to the Senegal, and 2.5% to the Cameroon. We did not find any significant difference between the haplotype distribution among adults and children and among sickle cell patients and traits. Only 8.6% of the patients have homozygosity for the Benin haplotype. These results show a very high frequency of admixture in our African origin population.
镰状细胞贫血和α地中海贫血在委内瑞拉分布不均，沿海地区（海平面）发病率高，山区病例较少。我们的大多数人口是欧洲人（西班牙殖民者）、非洲人（奴隶）和美洲印第安人的种族混合体。我们研究的目的是确定β珠蛋白单倍型的起源、年龄和生存依赖性，以及我们人群中不同非洲群体之间的混合情况。还研究了α（3.7）珠蛋白基因缺失状态，发现其频率非常高。对191名无亲缘关系患者（81名HbS纯合子患者、15名HbS、HbC、HbD与β地中海贫血复合杂合子患者以及95名镰状细胞性状患者）的外周血DNA进行了研究。β染色体与贝宁单倍型的连锁率为51%，与中非共和国单倍型的连锁率为29.5%，与塞内加尔单倍型的连锁率为12.5%，与喀麦隆单倍型的连锁率为2.5%。我们没有发现成人和儿童之间以及镰状细胞患者和性状携带者之间的单倍型分布有任何显著差异。只有8.6%的患者贝宁单倍型呈纯合状态。这些结果表明我们非洲裔人群中的混合频率非常高。
