Association of peptidylarginine deiminase Ⅳ gene polymorphisms and its expression with rheumatoid arthritis in Chinese patients / 中华风湿病学杂志

ABSTRACT

Objective The current study is aimed to investigate the association of single nucleotide polymorphisms and gene expression in peptidylarginine deiminase Ⅳ (PADI4) with rheumatoid arthritis (RA).Methods The gene expression of PADI4 was examined using real-time quantitative reverse transcription-polymcrase chain reaction (RT-PCR) in 70 patients with RA and 81 healthy controls. Four exonie SNPs of the PADI4 gene (PADI4_89, _90, _92, _104) were genotyped using DNA sequencing and TA cloning.Results The distribution of PADI4_89, _90, _104 SNPs in RA was different from that of healthy controls. The increased RA susceptibility was significantly associated with minor alleles. When haplotypes were construe -ted with 4 SNPs, two major haplotypes, ACCC and GTGT were found in all samples, and GTGT haplo-type (carrying only the minor alleles) was significandy associated with increased RA susceptibility (P<0.01)in comparison with the reference haplotype ACCC. There was over expression of PADI4 in RA than controls(P<0.05). C, enotypes carrying the minor alleles had higher expression level of PADI4 in RA and controls than those with the common alleles. Conclusion PADI4 SNPs and haplotypes are associated with RA susceptibility in Chinese. PADI4 is over-expressed in the blood of RA patients, and there is significant association between the haplotypes and expression level of the PADI4 gene.