温州籍轻型β珠蛋白合成障碍性贫血患者的基因多态性

Analysis of Single Nucleotide Polymorphism in the Human β-globin Gene of Patients with Minor β-thalassemia from Wenzhou

本研究旨在对14例临床诊断的温州籍轻型β珠蛋白合成障碍性贫血患者的血液学及分子生物学进行分析,测定其PCR产物序列,找出引起该病的致病突变位点并进行单核苷酸多态性分析。对临床诊断的患者抽取静脉血,EDTA-K2抗凝,及时提取模板,设计相关引物,进行PCR扩增后测序,最后经过序列比对和分析,找出引起β珠蛋白合成障碍性贫血的致病突变位点。结果表明:14例标本的DNA扩增产物测序分析中发现4例在IVS-2-654位点发生了C→T的杂合突变;1例为CD41/42位-TTCT缺失;2个位点存在单核苷酸多态性,分别是外显子1第59位的T/C多态性、IVS-2 nt 665,T/C多态性。结论:温州籍轻型β珠蛋白合成障碍性贫血患者单核苷酸多态性具有一定的特殊性;发现了两种基因突变类型,分别为IVS-2-654 C→T的杂合突变和CD41/42位-TTCT缺失。

This study was aimed to analyze the hematologic and molecular biologic chracteristics of 14 Wenzhou patients with minor β-thalassemia, to find out the mutation sites responsible for the disease by detecting sequences of PCR products and to analyze the single nucleotide polymorphism. The peripheral blood of patients was collected intravenously and was anticoagulated with EDTA-K2 ; then the tamplates from blood samples were extracted, the related primers were disigned for sequencing the products amplified by PCR; finally mutation sites resulting in β-thalassemia were found through comparison and analysis of sequences. The resuts indicated that the C→T heterozygous mutation occurred at the IVS-2 -654 site in 4 cases; the TTCT deficiency appeared at CD41/42 site in 1 case; in 2 sites existed single nucleotide polymorphisms occurring at the 59th site of exon 1 （T/C, CAT/CAC, His） and IVS-2 nt 665（T/C）. It is concluded that singte nucleotide polymorphism of minor β-thalassemia patients born in Wenzhou had specificity, this study found too kinds of gene mutations which are IVS-2 -654 C→T heterozygous mulation and CD41/CD42 site-TTCT dificiency.