类风湿性关节炎患者血细胞协同刺激分子B7-H3基因的单核苷酸多态性分析

Single nucleotide polymorphisms of B7-H3 gene in blood cells of patients with rheumatoid arthritis

目的拟通过体外直接测序方法发现B7-H3基因存在的单核苷酸多态性(SNP)位点,探讨其与类风湿性关节炎(RA)易感性之间的关联。方法先采用直接测序法分析86例RA患者及73例健康人B7-H3基因序列,发现SNP位点;再结合序列特异性引物聚合酶链反应(SSP-PCR)检测377例RA患者及321例健康对照组共计6个位点的SNP。结果在汉族人群中发现B7-H3基因编码区及部分内含子中存在6个SNP位点,分别位于基因的第19 589[chr.73 992 036、19 630(chr.73 992 077)、19 948(chr.73 992 394)、19 956(chr.73 992 602)、20 214(chr.73 992 660)、28 969(chr.73 993 889)]位。其中前5个位点的基因型频数和等位基因频数在RA组及健康组中的分布存在显著性差异(P<0.05)。结论发现汉族人群B7-H3基因6个位点存在单核苷酸多态性变异,其中5个位点与汉族人群的RA发生相关。

Objective To explore the single nucleotide polymorphisms（ SNPs） of co-stimulatory molecule B7-H3 gene in blood cells of patients with rheumatoid arthritis（ RA） through the in vitro sequencing method and analyze the correlation between the SNPs and the susceptibility of RA. Methods We sequenced directly B7-H3 gene in 86 cases of RA patients and73 cases of health controls,and then sequence specific primer-PCR（ SSP-PCR） genotyping method was carried out in 377 cases of RA patients and 321 health controls for 6 sites of SNPs. Results Six sites of SNPs 19 589[chr. 73 992 036,19 630（ chr.73 992 077）,19 948（ chr. 73 992 394）,19 956（ chr. 73 992 602）,20 214（ chr. 73 992 660）,28 969（ chr. 73 993 889） ]were found in the CDS region and some introns of B7-H3 gene. Apart from 28 969 site（ chr. 73 993 889）,the others had significant differences in the genotypic frequency and allelic frequency between RA patients and health controls（ P〈0. 05）. Conclusion Six sites of B7-H3 gene have SNP variations and five sites are related to the pathogenesis of RA in Han populations.