Zhang Qiang, Fan Xin, Xu Mingli, Zhang Yijia, Xu Huiling, Wen Xiaojun, Zhou Wanjun
a Department of Medical Genetics , School of Basic Medical Sciences, Southern Medical University , Guangzhou , Guangdong Province , People's Republic of China.
b Department of Genetic Metabolism , Prenatal Diagnostic Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region , Nanning , Guangxi Zhuang Autonomous Region , People's Republic of China.
Hemoglobin. 2017 May;41(3):189-192. doi: 10.1080/03630269.2017.1366917.
Thalassemia is the most common monogenic disease, with the highest incidence in Guangxi Zhuang Autonomous Region, People's Republic of China (PRC). The blood test result was not consistent with α-globin gene testing in one of the patients during daily screening. It was confirmed that there were multiple mutations at the α2-globin gene polyadenylation (polyA) signal site: HBA2: c.*64(T>C), HBA2: c.*68(A>C), HBA2: c.*71(G>A), HBA2: c.*74(C>A), HBA2: c.*82(G>A), HBA2: c.*92(A>G) and HBA2: c.*98(T>C) and compound - -/αα by sequencing of the HBA1 and HBA2 genes of the proband and core family members. After that, we found a further two cases of unrelated patients with this type of mutation. The mutation is not an accidental phenomenon, and likely to occur with a considerable incidence in Guangxi Zhuang Autonomous Region, PRC. We analyzed the hematological manifestations of this type of thalassemia and showed that it was a Hb H (β4) disease caused by rare mutations. We suggest that it is essential to pay attention to this mutation during future clinical diagnoses and genetic counseling of patients.
地中海贫血是最常见的单基因疾病，在中华人民共和国广西壮族自治区发病率最高。在日常筛查中，其中一名患者的血液检测结果与α珠蛋白基因检测结果不一致。经确认，α2珠蛋白基因多聚腺苷酸化（polyA）信号位点存在多个突变：HBA2: c.*64(T>C)、HBA2: c.*68(A>C)、HBA2: c.*71(G>A)、HBA2: c.*74(C>A)、HBA2: c.*82(G>A)、HBA2: c.*92(A>G) 和 HBA2: c.*98(T>C)，通过对先证者及其核心家庭成员的HBA1和HBA2基因进行测序，发现其基因型为复合--/αα。此后，我们又发现了另外两例具有这种突变类型的无关患者。这种突变并非偶然现象，在中华人民共和国广西壮族自治区可能有相当高的发病率。我们分析了这种类型地中海贫血的血液学表现，结果表明它是由罕见突变引起的血红蛋白H（β4）病。我们建议，在未来对患者进行临床诊断和遗传咨询时，必须关注这种突变。
