两省交界地区β地中海贫血复合缺失型α地中海贫血的发生率及基因诊断

Incidence and genetic diagnosis of β-thalassemia compound α-thalassemia in the border area of two provinces

目的研究两省(广东、广西)交界地区β地中海贫血杂合子复合缺失型α地中海贫血的基因型及发生率。方法采用RDB/PCR技术检测17种中国人较常见β地中海贫血基因突变位点。采用单管多重PCR技术检测3种缺失型α地中海贫血(左缺失-α4.2缺失,右缺失-α3.7缺失,东南亚型缺失__SEA)。结果在217例β地中海贫血杂合子标本中共检出30例复合缺失型α地中海贫血,检出率为13.82%。其中β地中海贫血杂合子合并__SEA/αα20例(9.21%),合并-α3.7/αα7例(3.22%),合并-α4.2/αα2例(0.92%),合并__SEA/-α4.21例(0.46%)。检出的30例β地中海贫血基因突变类型共有8种,分别是CD41-42(-TCTT)、TATAboxnt-28(A→G)、CD17(A→T)、CD71-72(+A)、IVS-Ⅱnt654(C→T)、βE(G→A)、TATAboxnt-29(A→G)、CD43(G→T)。结论两省交界地区人群β地中海贫血杂合子复合缺失型α地中海贫血的发生率为13.82%,β地中海贫血基因突变类型呈现多样性。在遗传咨询和产前诊断中应引起重视。

Objective To investigate the genotype and incidence of β-thalassemia compound α-thalassemia in the border area of Guangdong and Guangxi.Methods The 17 β-thalassemia mutation were detected by reverse dot blot（RDB）.Three kinds of deletional α-thalassemia were detected by gap-PCR.Results Of 217 β-thalassemia,30 were detected to be combined with α-thalassemia：20 combined with__SEA/αα（9.21%）,7 combined with-α3.7/αα（3.22%）,2 combined with-α4.2/αα（0.92%）,1 combined with__SEA/-α4.2（0.46%）.In the 30 heterozygotes,8 types mutation were as follow：CD41-42（-TCTT）,TATAboxnt-28（A → G）,CD17（A → T）,CD71-72（＋ A）,IVS-Ⅱnt654（C → T）,βE（G → A）,TATAboxnt-29（A → G）,CD43（G → T）.Conclusion 13.82% of β-thalassemia compound α-thalassemia were found in the border area of Guangdong and Guangxi.The type of gene mutation in β-thalassemia were multifarious.It should be pay attention to the genetic counseling and prenatal diagnosis.