基因测序在β地中海贫血稀有突变患者产前诊断中的应用

Prenatal diagnosis for the rare beta-thalassemia mutation carriers with DNA sequencing

目的:应用直接基因测序为β地中海贫血稀有突变患者进行产前基因诊断。方法:产前行常规血液学筛查,对怀疑β地中海贫血的患者行反向点杂交检测常见的17种突变,对未发现突变的患者采用直接基因测序,确证是否携带β地中海贫血稀有突变,对同时携带稀有β地中海贫血基因突变的夫妇取孕妇脐血或行羊水产前基因诊断。结果:为两对携带稀有β地中海贫血基因突变的夫妇行产前基因诊断,其中一对夫妇的丈夫为CD41-42(-TTCT)杂合突变,孕妇为CD6(GAG→AAG)/N杂合突变,胎儿羊水为CD6(GAG→AAG)/N杂合突变;第二对夫妇的丈夫为CD22(GAA→GCA)/N杂合突变,孕妇为CD56(GGC→GAC)/N杂合突变,胎儿脐血未发现突变。结论:联合反向点杂交和直接基因测序技术可为携带稀有β地中海贫血基因突变的夫妇提供产前基因诊断。

Objective： Prenatal diagnosis was performed for the rare beta-thalassemia mutation carriers by direct DNA sequencing of the entire β-globin gene. Methods： Screened the couples by cell counter and hemoglobin analysis, then identified the commonest known 17 types mutation by reverse blot dot. For the doubtful patient who was not detected mutation,direct DNA sequencing of the entire β-globin gene. Prenatal diagnosis was performed for the couples who was identified as rare beta-thalassemia mutation carriers. Results： One pregnant was heterozygote of CD6（GAG→AAG）/N and her husband was heterozygote of CD41-42（-TTCT）,her fetus was heterozygote of CD6（GAG→AAG）/N.The other pregnant was CD56 （GGC→GAC）/N heterozygote of and her husband was heterozygote of CD22（GAA→GCA）/N,her fetus was not detected any reported mutation. Conclusion： Direct DNA sequencing of the entire β-globin gene is a effective technology of prenatal diagnosis for the rare beta-thalassemia mutation carriers.