5个中间型β-地中海贫血家系临床结果分析

目的了解现行PCR-RDB法对中间型β-地贫基因诊断的准确性。方法对5个中间型β-地贫家系进行血常规、血红蛋白电泳和β-地贫基因的PCR-RDB法检测,并用长链PCR法检测家系1和家系2中的先证者及母亲的β-地贫基因的缺失突变。结果 5例先证者HbF含量均增高,其中2例为轻度贫血,3例为中度贫血;4例先证者PCR-RDB法结果为杂合子与其表现的临床症状不符,1例先证者PCR-RDB结果为纯合子与父母基因检测结果不符;先证者1及其母亲长链PCR法显示阴性,先证者2及其母亲长链PCR法均为东南亚（SEA）缺失型HPFH。结论若在产前诊断时仅用PCR-RDB法检测β-地贫基因,会造成缺失型β-地贫基因漏诊,引起一系列严重的社会问题。

Analysis of the clinical results of 5 families with β-thalassemia intermedia

Objective To evaluate the accuracy of the diagnosis of intermediate β-thalassemia by PCR-RDB.Methods Blood samples from the members of five families with β-thalassemia intermedia were analyzed.These included the routine routine test,hemoglobin electrophoresis as well as β-thalassemia gene by PCR-RDB.The β-thalassemia gene defects of the proband and the mother in the family-1 and-2 were determined by long chain PCR.Results Two of the five probands had mild anemia and three had intermediate anemia.The content of HbF in all probands was increased.The β-thalassemia genotypes of the four probands were found to be heterozygotes and showed mismatching with their clinical symptoms,and one proband was homozygote and showed mismatching with his parents.The β-thalassemia gene defects of both proband 1 and her mother showed negative by long chain PCR,and both of the proband 2 and his mother showed SEA HPFH deletion.Conclusion β-thalassemia gene defects would be miss diagnosed if PCR-RDB was used only in the prenatal diagnosis of β-thalassemia gene.