Association of interferon induced helicase C domain 1 gene polymorphism and polymyositis/dermatom-yositis in Chinese Han patients from Jiangsu area / 中华风湿病学杂志

ABSTRACT

Objective To explore the associations between interferon induced helicase C domain 1 (IFIH1) gene single nucleotide polymorphism (SNP) rs1990760 C >T and polymyositis/dermatomyositis (PM/DM) in Chinese Han patients from Jiangsu area. Methods A total of 183 PM/DM patients and 400 healthy controls were included. SNP typing was performed by Taqman MGB probe method. The distributions of genotypes and alleles and Hardy-Weinberg equilibrium (HWE) were examined by χ2 tests or Fisherˊs exact tests. Results The distribution of IFIH1 rs1990760 genotypes of all patients group and the control group were consistent with HWE. The frequencies of T and C alleles were not significantly different between the PM/DM group (20.8% and 79.2%, respectively), the DM group (20.9% and 79.1%, respectively), the PM group (20.5%and 79.5%, respectively) and control group (18.0%and 82.0%, respectively). In recessive model (TT vs CT+CC) and additive model (TT vs CC), the frequencies of TT genotype in PM/DM group (6.6% vs 2.8%; χ2=4.8 and 4.54, respectively; both P=0.03) and in DM with interstitial lung disease (ILD) group (8.3% vs 2.8%;χ2=4.84 and 4.41, respectively; P=0.03 and 0.04, respectively) were significantly higher than those in the control group.In recessive model (TT vs CT+CC), the frequency of TT genotype in PM without ILD group was significantly higher than that in the control group (9.8% vs 2.8%, χ2=5.56, P=0.04). The genotype and allele distributions of rs1990760 were not significantly different between the anti-MDA5 positive group and control group. Conclusion The rs1990760 TT genotype of IFIH1 gene may be associated with the susceptibility of PM/DM in Jiangsu Han Chinese population, and the associations may differ based on the ILD status.