471例儿童α地中海贫血缺失型基因谱分析

Spectrum of gene deletion in 471 children with α-thalassemia

摘要:

目的：探讨儿童α地中海贫血（α地贫）常见缺失型基因谱的分布特征。方法：在佛山市妇幼保健院就诊和体检的儿童中，血细胞分析检测红细胞体积（MCV）＜82 fl 者抽取静脉血2 mL（EDTA抗凝），采用 GAP-PCR 法进行α地贫基因分析。结果：血细胞分析 MCV＜82 fl 者 1341 例，检出α地贫 471 人，检出率为 35.1%，且随年龄增长而增高。基因缺失以东南亚缺失型（--SEA）为主，占75.3%；其次为右侧缺失型（-а3.7），占17.0%；左侧缺失型（-а4.2）占7.7%。基因型分布前3位分别是：--SEA/аа（73.2%），аа/-а3.7（12.5%）和 -SEA/-а3.7（5.5%）。结论：对MCV＜82 fl 儿童进行α地贫的基因诊断是必要的。该资料中α地贫患儿基因缺失以东南亚缺失型（--SEA）占主导地位，基因型以 --SEA/aa多见。

Abstract:

OBJECTIVE: To study the distribution of common α-thalassemia gene deletion in children. METHODS: Blood cell analysis was performed on children who visited the clinic of the Foshan Women and Children’s Hospital. Blood samples (2 mL, EDTA anticoagulant) was collected from children with MCV＜82 fl for analysis of α-thalassemia gene using the GAP-PCR method. RESULTS: MCV＜82 fl was found in 1341 children. Of the 1341 children, 471 (35.1%) were diagnosed with α-thalassemia. The prevalence of α-thalassemia increased with increasing age. --SEA was a major type of α-thalassemia gene deletion (75.3%), followed by -a3.7 (17.0%) and -a4.2 (7.7%) in the 471 patients. The top three genotypes were --SEA/аа (73.2%), аа/-а3.7 (12.5%) and --SEA/-а3.7 (5.5%). CONCLUSIONS: Genetic testing is necessary for the diagnosis of α-thalassemia in children with MCV＜82 fl. --SEA is a common type of α-thalassemia gene deletion, and -SEA/aa is a common gene type of α-thalassemia in the subjects of this study.