Department of Medical and Molecular Genetics, Dongguan Institute of Pediatrics, Dongguan, China.
Medical Laboratory, Dongguan Children's Hospital, Dongguan, China.
J Clin Lab Anal. 2021 Feb;35(2):e23596. doi: 10.1002/jcla.23596. Epub 2020 Sep 28.
Thalassemia is a common inherited hematological disease in tropical and subtropical regions. This study aimed to investigate the mutation spectrum of thalassemia in the Dongguan region of southern China and comprehensively analyze hematologic features of thalassemia carriers with various types of globin mutations.
A hematological screening including hematological indices such as mean corpuscular volume (MCV), mean corpuscular hemoglobin content (MCH), and mean corpuscular hemoglobin concentration (MCHC) was conducted in 19 442 people from Dongguan region, Guangdong province of China. Then, 4891 suspected thalassemia carriers were further investigated by genetic analysis of combined NGS and gap-PCR.
Totally, 2319 (11.9%) cases were diagnosed as carriers of thalassemia, of which 1483 cases (7.6%) were α-thalassemia, 741 cases (3.8%) were β-thalassemia, and 95 cases (0.5%) were co-inheritance of α- and β-thalassemia. In α-thalassemia carriers, the phenotypic severity increases with the number of nonfunctional α-globin genes. The patients with - /α α genotype have less severe clinical phenotypes than those with other Hb H diseases. As for β-thalassemia, the MCV and MCH in both β and β carriers are markedly reduced.
This is the first comprehensive molecular epidemiological survey and hematological profiling of thalassemia in Dongguan area. This study will be benefit for genetic counseling in the clinic and may help pediatricians to make a correct diagnosis of different types of thalassemia.
地中海贫血是热带和亚热带地区常见的遗传性血液病。本研究旨在调查中国南方东莞市地中海贫血的突变谱,并综合分析各种珠蛋白突变的地中海贫血携带者的血液学特征。
对来自中国广东省东莞市的 19442 人进行了一项包括平均红细胞体积(MCV)、平均红细胞血红蛋白含量(MCH)和平均红细胞血红蛋白浓度(MCHC)等血液学指标的血液学筛查。然后,对 4891 名疑似地中海贫血携带者进行了联合 NGS 和 gap-PCR 基因分析。
共诊断出 2319 例(11.9%)为地中海贫血携带者,其中 1483 例(7.6%)为α-地中海贫血,741 例(3.8%)为β-地中海贫血,95 例(0.5%)为α-和β-地中海贫血共遗传。在α-地中海贫血携带者中,非功能α-珠蛋白基因数量的增加导致表型严重程度的增加。-/αα基因型的患者比其他 Hb H 疾病的患者临床表型较轻。对于β-地中海贫血,β和β携带者的 MCV 和 MCH 均明显降低。
这是东莞市首次全面的地中海贫血分子流行病学调查和血液学特征分析。本研究将有助于临床遗传咨询,并有助于儿科医生对不同类型地中海贫血做出正确诊断。