泰国缺失型α地中海贫血1的产前诊断分析

Prenatal diagnosis of Thailand deletion of α-thalassemia 1 families

目的对11个泰国缺失型α地中海贫血1家系进行分析及产前诊断，以指导临床遗传咨询。方法对2009年5月至2015年9月在福建省妇幼保健院进行产前诊断的11个泰国缺失型α地中海贫血1家系资料进行回顾性分析。地中海贫血基因诊断采用跨越断裂点聚合酶反应（gap－PCR）和反向斑点杂交技术等方法。结果1个家系的夫妇双方均检测出泰国缺失型α地中海贫血1基因突变；10个家系为夫妇一方检出泰国缺失型α地中海贫血1基因突变，而另一方为常见的α地中海贫血基因突变（其中有1例合并β地中海贫血基因突变）。检出泰国缺失型α地中海贫血1基因突变的家系成员均出现红细胞平均体积和红细胞平均血红蛋白量降低。12个胎儿产前诊断，检出4例血红蛋白Bart＇s胎儿水肿综合征，5例地中海贫血杂合子，3个胎儿基因型正常。结论血液学表型阳性而常规α地中海贫血基因检测未见异常的人群，尤其是有胎儿水肿综合征或血红蛋白H病生育史的家庭需要引起临床医生的重视，应考虑罕见的泰国缺失型α地中海贫血1。对高风险家庭进行产前诊断，对于优生优育具有重要的指导意义。

ObjectiveTo conduct analysis and prenatal diagnosis on 11 couples carrying Thailand deletion （--THΑI） α-thalassemia 1, so as to provide information for clinical genetic counseling on α-thalassemia 1.MethodsAltogether 11 Thailand deletion （--THΑI） α-thalassemia 1 families were collected from Fujian Maternal and Children Health Hospital from May 2009 to September 2015. Gap-polymerase chain reaction （gap-PCR） and reverse dot blot （RDB） technology were used to detect the thalassemia mutations in the couples and fetuses.ResultsIn one family, Thailand deletion α-thalassemia 1 was detected in both the pregnant woman and her husband. In 10 families, Thailand deletion α-thalassemia 1 was detected in either the pregnant women or the husband, while the spouses had α-thalassemia heterozygote （1 combined with β thalassemia heterozygote）. Thailand deletion α-thalassemia 1 family members all had lower mean corpuscular volume （MCV） and mean corpuscular hemoglobin （MCH）. In prenatal diagnosis of the 12 fetuses, 4 fetuses were found with hemoglobin（Hb） Bart＇s hydrops fetalis syndrome, 5 were with α-thalassemia heterozygote, and 3 were normal.ConclusionsFor couples with positive hematological phenotype but normal results in routine genetic examination of α-thalassemia, attention should be paid especially for with a history of having babies of hydrops fetalis syndrome or hemoglobin H disease. It is necessary to consider the possibility of the rare Thailand deletion （--THΑI） α-thalassemia 1. Prenatal diagnosis for high-risk families plays an important role.