Millimono Tamba S, Loua Kovana M, Rath Silvia L, Relvas Luis, Bento Celeste, Diakite Mandiou, Jarvis Martin, Daries Nathalie, Ribeiro Leticia M, Manco Licínio, Kaeda Jaspal S
Department of Haematology, Donka Hospital, Conakry, Republic de Guinée.
Hemoglobin. 2012;36(1):25-37. doi: 10.3109/03630269.2011.600491. Epub 2011 Sep 19.
Reliable and accurate epidemiological data is a prerequisite for a cost effective screening program for inherited disorders, which however, is lacking in a number of developing countries. Here we report the first detailed population study in the Republic of Guinea, a sub-Saharan West African country, designed to assess the frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency and hemoglobinopathies, including screening for thalassemia. Peripheral blood samples from 187 Guinean adults were screened for hemoglobin (Hb) variants by standard hematological methods. One hundred and ten samples from males were screened for G6PD deficiency by the fluorescent spot test. Molecular analysis was performed for the most common α-thalassemia (α-thal) deletions, β-globin gene mutations, G6PD variants B (376A), A (376G), A- (376G/202A) and Betica (376G/968C), using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) or sequencing. Of the 187 subjects screened, 36 were heterozygous for Hb S [β6(A3)Glu→Val, GAG>GTG] (allele frequency 9.62%). Sixty-four subjects were heterozygous and seven were homozygous for the -α(3.7) kb deletion (allele frequency 20.85%). β-Thalassemia alleles were detected in five subjects, four with the -29 (A>G) mutation (allele frequency 1.07%) and one with codon 15 (TGG>TAG) (allele frequency 0.96%). The G6PD A- and G6PD Betica deficient variants were highly prevalent with a frequency of 5.7 and 3.3%, respectively. While we did not test for ferritin levels or α(0)-thal, four females (5.2%) had red cell indices strongly suggestive of iron deficient anemia: Hb <9.7 g/dL; MCH <19.3 pg; MCV <68.2; MCHC <31.6 g/dl; RDW >19.8%. Our results are consistent with high frequency of alleles such as Hb S, α-thal and G6PD deficient alleles associated with malaria resistance. Finding a 9.6% Hb S allele frequency supports the notion for a proficient neonatal screening to identify the sickle cell patients, who might benefit from early prophylactic treatment for infections. The incidence of significant iron deficient anemia in women is lower than expected in an under developed country.
可靠且准确的流行病学数据是开展具有成本效益的遗传性疾病筛查项目的前提条件，然而，许多发展中国家都缺乏此类数据。在此，我们报告了在撒哈拉以南的西非国家几内亚共和国进行的首次详细人群研究，该研究旨在评估葡萄糖-6-磷酸脱氢酶（G6PD）缺乏症和血红蛋白病的发生率，包括地中海贫血筛查。通过标准血液学方法对187名几内亚成年人的外周血样本进行血红蛋白（Hb）变异体筛查。对110份男性样本采用荧光斑点试验筛查G6PD缺乏症。使用聚合酶链反应（PCR）、限制性片段长度多态性（RFLP）或测序技术，对最常见的α地中海贫血（α-thal）缺失、β珠蛋白基因突变、G6PD变异体B（376A）、A（376G）、A-（376G/202A）和贝蒂卡（376G/968C）进行分子分析。在187名接受筛查的受试者中，36人是Hb S[β6（A3）Glu→Val，GAG>GTG]杂合子（等位基因频率9.62%）。64人是-α（3.7）kb缺失杂合子，7人是纯合子（等位基因频率20.85%）。在5名受试者中检测到β地中海贫血等位基因，4人携带-29（A>G）突变（等位基因频率1.07%），1人携带密码子15（TGG>TAG）（等位基因频率0.96%）。G6PD A-和G6PD贝蒂卡缺乏变异体的发生率很高，分别为5.7%和3.3%。虽然我们没有检测铁蛋白水平或α（0）-thal，但4名女性（5.2%）的红细胞指数强烈提示缺铁性贫血：Hb<9.7 g/dL；MCH<19.3 pg；MCV<68.2；MCHC<31.6 g/dl；RDW>19.8%。我们的结果与Hb S、α-thal和G6PD缺乏等位基因等与疟疾抗性相关的等位基因的高频率一致。发现9.6%的Hb S等位基因频率支持进行有效的新生儿筛查以识别镰状细胞病患者的观点，这些患者可能从早期感染预防性治疗中受益。在一个欠发达国家，女性中严重缺铁性贫血的发生率低于预期。
