泰国缺失型α地中海贫血的家系分析及产前诊断

Diagnosis and prenatal diagnosis to families with THAI deletionα-thalassemia

目的对3个泰国缺失型α地中海贫血家系进行分析及产前诊断。方法采集家系成员外周血进行血细胞分析及毛细管电泳血红蛋白分析;采集外周血及羊水、绒毛采用裂隙聚合酶链反应(GapPCR)以及PCR结合反向点杂交(PCR-RDB)方法进行常见6种α珠蛋白基因突变的鉴定;采用裂隙聚合酶链反应(Gap-PCR)方法进行泰国缺失型α地贫和菲律宾缺失型α地贫基因检测。结果在3个家系中检测到2例泰国缺失型α地中海贫血携带者(—~THAI)/αα)及1例泰国缺失型复合4.2缺失型α珠蛋白基因缺失导致的血红蛋白H病(—~THAI/-α^(4.2)),并对3个家系进行了产前诊断,检测到2个胎儿为泰国缺失型α地中海贫血携带者(—^(THAI)/αα)。结论MCV降低、Hb A_2降低而常规α地贫基因检测未见异常的人群,尤其是有水肿胎生育史的家庭需要引起临床医生的重视,要考虑到罕见缺失型α地中海贫血,对于常规检测提示为-α^(3.7)或-α^(4.2)纯合缺失而地贫筛查可疑HbH病者也要考虑罕见缺失型α地中海贫血的可能性,对高风险家庭要进行产前诊断对于优生优育具有重要意义。

Objective Analysis and prenatal diagnosis to 3 families with THAl deletion α-thalassemia.Method The family members＇ peripheral blood samples were analyzed by whole blood cell analysis and hemoglobin analysis with capillary zone electrophoresis（CZE）,α hemoglobin gene mutations were analysis by Gap-PCR and polymerase chain reaction-reverse dot blot（PCR-RDB） assay for peripheral blood samples,amniotic fluid and chorionic villus samples.Results 2 carriers of THAI deletion orthalassemia（—^THAI/αα） and 1 case of hemoglobin H disease（—^THAI/-α^4.2） were detected.2 of 3 fetuses were carriers of THAI deletion orthalassemia（—^THAI/αα）.Conclusions Clinicians should pay close attention to those who could be carriers of THAI deletion orthalassemia with reduced MCV and HbA_2.Prenatal diagnosis should be performed in high-risk families which has the vital significance for eugenic birth.