Genomic polymorphism at the interferon-induced helicase (IFIH1) locus contributes to Graves' disease susceptibility

J Clin Endocrinol Metab. 2007 Aug;92(8):3338-41. doi: 10.1210/jc.2007-0173. Epub 2007 May 29.

Abstract

Context: A recent large-scale analysis of nonsynonymous coding polymorphisms showed strong evidence that an alanine to threonine amino acid change at codon 946 of the interferon-induced helicase (IFIH1) gene (SNP ID rs1990760) was associated with type 1 diabetes. Previous investigations have also demonstrated that an intronic polymorphism (termed PD1.3; SNP ID rs11568821) in the programmed cell death (PDCD1) gene was associated with systemic lupus erythematosus and rheumatoid arthritis.

Objective: We sought to replicate these genetic associations in Graves' disease and autoimmune Addison's disease patient cohorts.

Patients and methods: A total of 602 Graves' disease subjects, 214 Addison's disease subjects, and 446 healthy controls were genotyped for the IFIH1 and PDCD1 single-nucleotide polymorphisms using mass spectrometer analysis of primer extension products (Sequenom).

Results: The alanine-carrying allele at the IFIH1 codon 946 polymorphism was present in 796 of 1204 (66%) Graves' disease patient alleles compared with 508 of 892 (57%) control subject alleles [odds ratio 1.47 (5-95% confidence interval, 1.23-1.76); P = 1.9 x 10(-5)]. In contrast, there was no association of alleles at this marker in autoimmune Addison's disease. Neither was there evidence for association in either patient cohort at the PD1.3 polymorphism.

Conclusions: We confirm a significant contribution of the Ala946Thr IFIH1 polymorphism to organ-specific autoimmune diseases, extending the range of conditions associated with this variant to include Graves' disease. This polymorphism may also contribute to several other autoimmune disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alleles
  • Cohort Studies
  • DEAD-box RNA Helicases / biosynthesis
  • DEAD-box RNA Helicases / genetics*
  • Female
  • Genotype
  • Graves Disease / genetics*
  • Graves Disease / physiopathology*
  • Humans
  • Interferon-Induced Helicase, IFIH1
  • Male
  • Odds Ratio
  • Polymorphism, Genetic
  • Polymorphism, Single Nucleotide

Substances

  • IFIH1 protein, human
  • DEAD-box RNA Helicases
  • Interferon-Induced Helicase, IFIH1