中国人类风湿关节炎与PAD14功能基因多态性及部分HLA-DRB1等位基因相关性研究

目的 分析类风湿关节炎(rheumatoid arthritis,RA)中4型肽精氨酸转亚胺基酶(peptidylarginine deiminase IV,PAD14)功能基因多态性,探讨PAD14基因多态性与RA易感性的关系,以及编码与RA易感性相关HLA共同表位(shared epitope,SE)的HLA-DRB1等位基因与PAD14基因多态性的相关性.方法 采用逆转录合成cDNA、DNA测序和T载体克隆方法 分析67例RA患者、81名正常人PAD14基因外显子4个单核苷酸多态性(single nucleotide polymorphisms,SNPs),包括PADH_89*A/G,PADl4 90*C/T,PAD1492*C/G,PAD14 104*C/T;采用PCR-序列特异性引物方法 分析HLA-DRB1.*-01、*04、* 10基因型.结果 RA患者PAD14 89、90、104位基因多态性分布与正常对照组比差异有统计学意义,携带PAD14少见等位基因者对RA的危险性较携带常见等位基因者显著增加;分析编码SE等位基因与PAD14 SNPs的相关性发现,SE+/PAD14_89G-携带者较SE-/PAD14_89G-携带者发生RA的危险性高4.7倍(OR=4.7,95%CI:1.6～13.4,P=0.003),携带SE+/PAD14 89G+者高5.6倍(OR=5.6,95%CI:2.0～15.7,P=0.003).在PAD14 90、92、104位均出现相似的情况.结论 PAD14功能基因多态性与中国人RA的易感性相关,编码SE的HLA-DRB1等位基因仍然是RA的重要遗传标记,而且HLA-DRB1等位基因与PAD14的少见等位基因间可能存在一定的协同作用.

Association of the PAD14 gene polymorphism and HLA-DRB1 shared epitope alleles with rheumatoid arthritis

Objective To investigate the association of single nueleotide polymorphisms(SNPs)of the peptidylarginine deiminaseⅣ(PADl4)and HLA-DRB1 shared epitope(SE)alleles with rheumatoid arthritis(RA)in a Chinese population.MethodsFour exonic SNPs of the PAD14 gene(PAD14_89*A/G,PADn_90*C/T,PAD14_92*C/G and PAD14_104*C/T)were genotyped in 67 unrelated patients with RA and 81 healthy controls,using cDNA sequencing and T vector cloning.HLA-DRB 1*0 1,*04and*10 subtypes were determined by polymerase chain reaction with sequence-specific primers(PCRSSP).Results The distributions of the 4 SNPs were different in the two groups,and increased RA susceptibility was significantly associated with the minor alleles of PAD14_89*G(P=0.023),PAD14_90*T(P=0.004).PADl4_104*T(P=0.003),and the haplotypes carrying the 4 minor alleles(P=0.008).HLA-DRBl SE alleles are composed of HLA-DRB1*0101,*0102,*0401,*0404,*0405,*0408,*0409,*0410 and*1001.Individuals carrying the SE alleles were associated with increased RA susceptibility(P=0.002).Individuals carrying both the SE alleles and minor alleles of the 4 SNPs were more susceptible to RA than individuals carrying neither the minor SNP alleles nor the SE alleles.Conclusion The PAD14 SNPs and haplotypes are associated with RA susceptibility in Chinese.HLADRBl shared epitope is also fin important risky factor for RA.There may exist certain synergistic effect between the PAD14 minor alleles and the HLA-DRB1 shared epitope.