屈艳霞，陈桂兰，唐　盈，江　帆，左连东，辜俊梅，李志华

广州市非缺失型α-地贫基因诊断和产前诊断结果分析

屈艳霞1，陈桂兰1，唐盈1，江帆1，左连东1，辜俊梅2，李志华3

（1. 广 州市妇女儿童医疗中心，广东广州510623；2. 番禺区人口和计划生育技术服务站，广东广州 518000；3. 广 州医科大学附属第三医院，广东广州510150）

目的： 分析广州市非缺失型α-地中海贫血(α-地贫)的临床特征、基因突变类型及构成比，为临床遗传咨询提供依据。方法：259例受检者均进行血液常规和高效液相色谱分析(HPLC)，筛查阳性者采用跨越断裂点PCR(Gap-PCR)和PCR结合反向杂交(PCR-RDB)技术进行α-地贫基因分析。夫妇为同型α-地贫携带者进一步行胎儿α-地贫基因诊断，产后随防。结果：259例受检者中，ααQS/αα 170例、ααWS/αα 43例、ααCS/αα 34例、--SEA/ααQS6例、--SEA/ααCS4例、-α3.7/ααQS1例、-α4.2/ααQS1例。同性别的患者3种非缺失型α-地贫红细胞平均体积(MCV)、红细胞平均血红蛋白量(MCH)比较差异有统计学意义(P＜0.05)，而血红蛋白(HGB)比较差异无统计学意义(P＞0.05)。经产前基因诊断检出非缺失型HbH(--SEA/ααT)病胎儿5例，胎儿引产后留脐血进行复核，均与产前基因诊断结果一致。结论：广州市非缺失型α-地贫发生率高，以ααQS/αα最常见，对疑似非缺失型α-地贫携带者进行基因检测，可显著降低非缺失型HbH病患儿的发生率。

非缺失型α-地贫；突变；基因诊断；产前诊断

【ABSTRACT】OBJECTIVE: To explore the gene mutation types and proportions of non-deletion αthalassemia，and to provide clinical basis for genetic counselling. METHODS：The gene mutation types and frequencies of 259 suspected non-deletion α-thalassemia patients were analyzed by Gap-PCR and PCR-RDB. 30 pregnant women whose husband had the same type of thalassemia received thalassemia prenatal diagnosis. We completed follow-up works. RESULTS：Among the 259 cases，170 cases of ααQS/αα，43 cases of ααWS/αα，34 cases of ααCS/αα，6 cases of --SEA/ααQS，4 cases of --SEA/ααCS，one case of -α3.7/ααQS，and one case of -α4.2/ααQSwere found. Compared with normal control group，there were statistical significances in MCV，MCH in different types of non-deletion α-thalassemia (P＜0.05). 5 fetuses with non-deletion HbH disease were confirmed by prenatal diagnosis. The results of postpartum follow-up were consistent with prenatal diagnoses. CONCLUSION：Guangzhou is a high incidence area of non-deletion α-thalassemia. The most common genotype is ααQS/αα. To reduce the birth of children with non-deletion HbH disease，non-deletion thalassemia genotype carriers s hould be t ested.

【KEY WORDS】non-deletion α-thalassemia；mutation；gene diagnosis；prenatal diagnosis

α-地中海贫血(α-地贫)是一种遗传性溶血性疾病，由α-珠蛋白基因缺陷所致。根据其基因改变类型的不同，可分为缺失型α-地贫和非缺失型α-地贫，前者是由于α-珠蛋白基因大片段缺失所致，是主要的变异类型；后者是由于α-珠蛋白基因或其调节序列发生点突变(包括单碱基置换和一个或几个核苷酸的缺失或插入)造成的。……