Molecular genotyping of G6PD mutations and Duffy blood group in Afro-descendant communities from Brazilian Amazon

Abstract Glucose-6-phosphate dehydrogenase deficiency (G6PDd) and Duffy-negative blood group are two red blood cells variants that confer protection against malaria. In this study, the distribution of the most common G6PD variants (G6PD*A-, GGPD*A and G6PD Mediterranean) and the major alleles of the Duffy blood group (FY*A, FY*B and FY*BES) were investigated in an Afro-descendant population from state of Pará, Brazilian Amazon. G6PD variants and Duffy blood group alleles were determined by TaqMan SNP genotyping assay. Overall, molecular genotyping revealed the presence of G6PD variants in 126 (24%) of the individuals studied (5% male and 19% female), and frequencies of the G6PD*A- and G6PD*A alleles were 0.061 and 0.104, respectively. Duffy blood group genotyping showed that 24.3% of people were Duffy-negative and 41.3% were heterozygous for FY*BES. The frequency of allele FY*BES was 41.0%. The results emphasize the need to monitor G6PD deficiency for the use of primaquine in the routine care of the Afro-descendant communities of the Trombetas, Erepecuru and Cumná rivers, evaluating the risks of hemolytic crisis in case of recurrence of malaria in the region. In addition, the possible greater protection against malaria conferred by these erythrocyte polymorphisms deserves to be better investigated and explored among these Afro-descendants.

摘要 葡萄糖-6-磷酸脱氢酶缺乏症（Glucose-6-phosphate dehydrogenase deficiency, G6PDd）与达菲阴性血型（Duffy-negative blood group）是两种可赋予机体抗疟疾保护作用的红细胞变异体。本研究针对巴西亚马逊地区帕拉州的非洲裔后裔人群，对最常见的G6PD变异体（G6PD*A-、G6PD*A及地中海型G6PD（G6PD Mediterranean））以及达菲血型的主要等位基因（FY*A、FY*B与FY*BES）的分布情况展开了调查。研究采用TaqMan SNP基因分型检测法（TaqMan SNP genotyping assay）对G6PD变异体与达菲血型等位基因开展分型检测。整体分子基因分型结果显示，126名（24%）受检个体携带G6PD变异体，其中男性占5%、女性占19%；G6PD*A-与G6PD*A等位基因的频率分别为0.061与0.104。达菲血型基因分型结果表明，24.3%的受试者为达菲阴性血型，41.3%的受试者携带FY*BES杂合等位基因，FY*BES等位基因的频率为41.0%。本研究结果强调，在特龙贝塔斯河、埃雷佩库鲁河与库姆纳河沿岸的非洲裔后裔社区开展常规诊疗、使用伯氨喹（primaquine）时，需对葡萄糖-6-磷酸脱氢酶缺乏症进行监测，以评估该地区疟疾复发时引发溶血性危象（hemolytic crisis）的风险。此外，这类红细胞多态性可能为疟疾提供更强的保护作用，这一现象值得在该非洲裔后裔人群中展开进一步研究与探索。