CTLA-4基因微卫星多态性与广西地区壮、汉族Graves病的相关性研究

目的:研究CTLA-4基因微卫星多态性与广西地区壮、汉族Graves 病(GD)的相关性.方法:112例广西地区壮、汉族GD患者和94例正常对照组,应用聚合酶链反应技术,检测CTLA-4外显子4的3'非翻译区包含(AT)nCTLA-4(AT)n]重复序列的特异性等位基因.结果:①广西地区壮族人细胞毒性T淋巴细胞相关抗原-4(CTLA-4)微卫星多态性有19种等位基因,汉族人有18种等位基因;②壮、汉族GD组与正常对照组比较,106 bp等位基因频率显著增高(P＜0.05),汉族正常对照组104 bp等位基因频率较GD组高(P＝0.01);③壮族正常对照组未发现104 bp等位基因高于GD组.结论:CTLA-4基因与广西壮、汉族GD患者明显相关,CTLA-4(AT)n 106 bp可能是广西壮、汉族GD的易感等位基因,104 bp可能是广西汉族GD的保护基因.

STUDIES ON THE ASSOCIATION OF THE MICROSATELLITE POLYMORPH OF THE CTLA-4 GENE WITH GRAVES DISEASE IN GUANGXI ZHUANG NATIONALITY AND HAN NATIONALITY

Objective: To investigate the relationship between the polymorphic (AT)n repeats in the 3'untranslated region of exon 4 of CTLA-4 geneCTLA-4(AT)n] and Graves disease(GD)of Zhuang nationality and Han nationality in Guangxi. Methods: The study group comprised 112 patients with GD and 94 normal controls, matched with patients in sex, age. Amplification of target DNA was carried out by the polymerase chain reaction (PCR), with primers 5'-GCC AGT GAT GCT AAA GGT TG-3' and 5'-AAC ATA CGT GGC TCT ATG CA-3'.The amplified products were electrophoresed by 8% polyacrylamid gel and followed by 0.1% silver staining. Some of the amplified products were sequenced directly. Result: 19 alleles of CTLA-4 gene microsatellite polymorphisms were found in Guangxi Zhuang nationality individuals. But there were 18 alleles of CTLA-4 gene microsatellite polymorphisms in Han nationality individuals. Long allele, 106 bp was apparently increased in patients with GD Zhuang nationality and Han nationality compared with healthy controls (P<0.05). The 104 bp allele in health control was higher than GD patients of Han nationality in Guangxi (P=0.01). But the same was not found in Zhuang nationality individuals. Conclusion:CTLA-4 gene microsatellite polymorphism was strongly associated with GD patients of Han and Zhuang nationality in Guangxi province. CTLA-4(AT)n 106 bp may be the susceptible gene in GD patients of Han and Zhuang nationality in Guangxi. CTLA-4(AT)n 104 bp may be the protective factor in GD patients of Han nationality.