Association analysis between TNIP1 gene polymorphisms and psoriasis vulgaris in a Han population from north China / 中华皮肤科杂志

ABSTRACT

Objective To investigate the association between polymorphisms in the tumor necrosis factor α-induced protein 3 (TNFAIP3)-interacting protein 1 (TNIP1) gene and psoriasis vulgaris in a Han population from north China.Methods Totally,465 patients with psoriasis vulgaris (PsV) and 476 healthy human controls were enrolled into the study.Five milliliters of venous blood samples were collected from these subjects after informed consent.Three single nucleotide polymorphisms (SNPs) in the TNIP1 gene,including rs17728338,rs3762999 and rs999556,were selected for genotyping with ligase detection reaction (LDR).With the PLINK 1.07 package,statistical analysis was carried out by using the chi-square test for comparisons of allele frequencies and genotype frequencies between the patient group and control group.The allelic odds ratio (OR) and its 95％ confidence interval (CI) were calculated.In addition,linkage disequilibrium analysis was performed for the three SNPs by calculating the r2 and D' values.Results There was a difference in the allele frequencies of the three SNPs between the patients with psoriasis vulgaris and controls,but the difference was statistically significant in only the allele frequencies of rs17728338,but not in those of the other two SNPs after Bonferroni correction.Under the dominant inheritance model,the genotype frequencies of the 3 SNPs all significantly differed between the patients and controls after Bonferroni correction (all P ＜ 0.016 7).Stratification analysis showed that there was a significant difference in the allele and genotype frequencies of the three SNPs between the patients with a family history and healthy controls (all P ＜ 0.016 7),and the frequency of A allele of rs17728338 was significantly lower in the controls than in the patients with psoriasis vulgaris,patients with early-onset psoriasis vulgaris (n =355),patients with late-onset psoriasis vulgaris (n =107),patients with a family history (n =68),and patients without a family history (n =394) (all P ＜ 0.0167).Strong linkage disequilibrium existed between rs3762999 and rs999556 (r2 =0.910,D' =0.982),and moderate linkage disequilibrium existed between rs17728338 and rs3762999 (r2 =0.371,D' =0.989) as well as rs999556 (r2 =0.353,D' =1).Conclusion The SNPs rs17728338,rs3762999 and rs999556 in the TNIP1 gene were associated with psoriasis vulgaris in the Chinese Han population.