Xiang Xiao-Hua, Leng Jun, Wang Di, Mo Li-Jun, Jiang Wei, Wei Chuan-Dong
Department of Laboratorial Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin 541199, Guangxi Zhuang Autonomous Region, China.
Department of Laboratorial Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin 541199, Guangxi Zhuang Autonomous Region, China,E-mail:
Zhongguo Shi Yan Xue Ye Xue Za Zhi. 2021 Jun;29(3):860-864. doi: 10.19746/j.cnki.issn.1009-2137.2021.03.032.
To analyze the gene defect types and distribution characteristics of α- and β-thalassemia in Lingui District of Guilin City, Guangxi, so as to provide scientific basis for genetic consultation and prevention measures.
A total of 6 496 suspected cases for screening the thalassemia during physical examination, premarital examination, pregnancy examination and hospitalization in the Second Affiliated Hospital of Guilin Medical University from May 2016 to October 2019 were analyzed. Gap-PCR, PCR-RDB and DNA sequencing techniques were used to detect the types and constituent ratios of gene defects in α- and β-thalassemia positive cases.
Among 6 496 suspected patients, 1 363 were thalassemia carriers, the total positive rate was 20.98%. There were 677 cases of single-gene deletion and 26 cases of double-gene detetion on the deletional α-thalassemia, 115 cases of non-deletion α-thalassemia mutation and 4 cases of deletion plus mutation. The positive rate of α-thalassemia was 12.66%. There were 11 gene abnormalities for α-thalassemia, of which --/αα (50.36%) was the most common, followed by -α/αα (23.84%); the main α-gene mutation was αα (6.93%). There were 514 β-thalassemia gene carriers, with a positive rate of 7.93%. In 12 types of β-gene mutations, CD41-42 (-TTCT) (55.64%) was the most common, followed by CD17 (A→T) (20.23%). There were 25 cases of double heterozygous α and β thalassemia (0.39%), of which -α/βCD17 (24%) and --/β41-42 (16%) were numerically dominant. Two of rare thalassemia genotypes were identified by sequencing, which were heterozygous mutations of Chinese Hong Kong type α thalassemia (HKαα/αα or HKαα/-α) and β gene mutations IVS-I (-2) or codon30 (A→G) β0, respectively.
Lingui district of Guilin city is a high incidence area of thalassemia. The mutation rate of α-thalassemia --/αα type deletion is relatively high, followed by that of the right deletion type (-α/αα). CD41-42 (-TTCT) has the highest mutation rate in β-thalassemia, followed by CD17(A→T). The results of this study provide reference data for the regional screening, diagnosis and treatment of thalassemia and eugenics.
分析广西桂林市临桂区α和β地中海贫血的基因缺陷类型及分布特征，为遗传咨询及预防措施提供科学依据。
对2016年5月至2019年10月在桂林医学院第二附属医院进行体检、婚前检查、孕期检查及住院治疗的6496例地中海贫血疑似筛查病例进行分析。采用缺口聚合酶链反应（Gap-PCR）、聚合酶链反应-反向点杂交（PCR-RDB）及DNA测序技术检测α和β地中海贫血阳性病例的基因缺陷类型及构成比。
6496例疑似患者中，地中海贫血携带者1363例，总阳性率为20.98%。缺失型α地中海贫血中，单基因缺失677例，双基因缺失26例；非缺失型α地中海贫血突变115例，缺失加突变4例。α地中海贫血阳性率为12.66%。α地中海贫血有11种基因异常，其中--/αα（50.36%）最为常见，其次是-α/αα（23.84%）；主要的α基因突变为αα（6.93%）。β地中海贫血基因携带者514例，阳性率为7.93%。在12种β基因突变类型中，CD41-42（-TTCT）（55.64%）最为常见，其次是CD17（A→T）（20.23%）。α和β地中海贫血双重杂合子25例（0.39%），其中-α/βCD17（24%）和--/β41-42（16%）数量占优。通过测序鉴定出2种罕见的地中海贫血基因型，分别为中国香港型α地中海贫血杂合突变（HKαα/αα或HKαα/-α）和β基因突变IVS-I（-2）或密码子30（A→G）β0。
桂林市临桂区是地中海贫血高发区。α地中海贫血--/αα型缺失突变率相对较高，其次是右侧缺失型（-α/αα）。β地中海贫血中CD41-42（-TTCT）突变率最高，其次是CD17（A→T）。本研究结果为地中海贫血的区域筛查、诊断、治疗及优生优育提供了参考数据。
