【摘要】 为了进一步完善和建立一套筛查我国α地中海贫血基因突变型的方法 ,研究我国南方两广地区α地中海贫血突变类型及分布情况 ,采用Gap PCR ,nested PCR ,PCR SSCP ,4P ASPCR及序列分析等方法 ,对 35 6例临床初诊为标准型和静止型α地中海贫血患者和 78例血红蛋白H(HbH)病患者进行基因筛查。结果表明 :35 6例标准型和静止型α地中海贫血患者中发现 SEA αα 2 95人 (82 .87% ) ,αα α α3.71人 (0 .2 8% ) ,αα α α4 .2 3人 (0 .84 % )αα ααCS3人 (0 .84 % ) ,αα ααQS1人 (0 .2 8% )和αα αWestmeadα 2人 (0 .5 6 % ) ,没有发现 α4 .2和 α3.7的纯合子患者 ;78例HbH病患者中 SEA αα- 3.72 9人 (37.2 % ) , SEA αα- 4.2 2 0人 (2 5 .6 % ) , SEA ααCS19人 (2 4 .3% ) , SEA ααQS 2人 (2 .6 % )。在 8例未能确定基因突变类型的HbH患者中 ,2例广西籍HbH患者的α 2基因第 6 5密码子 (第二外显子 )有一同义突变 [CD6 5 (GCC→GCG) ]。它与HbH病表型究竟有无关系 ,抑或是DNA单核苷酸多态位点 (SNPs) ,有待进一步研究证实。在方法学方面 ,本研究进一步完善了以PCR为基础的基因诊断方法 ,建立了一种改进的检出非缺失型点突变的 4P ASPCR方法 ,能准确、快速地用于诊断我国常见的缺更多还原

【Abstract】 There is a high prevalence of thalassemia in the South of China. To explore the genotype of α thalassemia as well as the distribution of α globin gene mutation in the South of China, 356 patients with heterozygote α + thalassemia, heterozygote α 0 or homozygote α + thalassemia and 78 patients with HbH were analyzed. The gene diagnosis methods including Gap PCR, nested PCR, PCR RE, PCR SSCP, 4P ASPCR and DNA sequence analysis were used. The results showed that among 356 patients, 295 patients with SEA/αα(82.87%), 1 patient with αα/α α 3.7 (0.28%), 3 patients with αα/α α 4.2 ( 0.84% ), 3 patients with αα/α CS α (0.84%), 1 patient with αα/αα QS (0.28%) and 2 patients with αα/α Westmead α(0.56%) were found. The homozygote with α 4.2 or α 3.7 was not found. In 78 patients with HbH, 29 patients with SEA/αα -3.7 (37.2%), 20 patients with SEA/αα 4.2 (25.6%), 19 patients with SEA/αα CS (24.3%), 2 patients with SEA/αα QS (2.6%) were detected, and other remaiming 8 patients were needed to be defined. Among the non defined 8 patients, the synonymous mutation with C→G transversion (GCC GCG) at codon 65 in the exon 2 of α 2 globin gene was detected in 2 unrelated HbH patients came from Guangxi province. Whether it correlated with the phenotype of HbH disease or it is only a single nucleotide polymorphism site (SNPs), should be confirmed in the future. In addition, a set of gene diagnosis methods based on PCR to screen deletion and non deletion genotypes of α thalassemia in Chinese was improved. A new method, 4P ASPCR, to detect Hb CS and Hb QS was also developed. The method was verified to be more accurate, time saving and economic. In conclusion, the genotypes of α thalassemia in Chinese are very complicated, the genotypes of α thalassemia in Chinese need to be further studied, the results of this reaserch probably have practical significance for the gene diagnosis or antenatal diagnosis of α thalassemia in the South of China.更多还原