title: Evaluation of genetic association between an ITGAM non-synonymous SNP (rs1143679) and multiple autoimmune diseases.
abstract: Many autoimmune diseases (ADs) share similar underlying pathology and have a tendency to cluster within families, supporting the involvement of shared susceptibility genes. To date, most of the genetic variants associated with systemic lupus erythematosus (SLE) susceptibility also show association with others ADs. ITGAM and its associated 'predisposing' variant (rs1143679, Arg77His), predicted to alter the tertiary structures of the ligand-binding domain of ITGAM, may play a key role for SLE pathogenesis. The aim of this study is to examine whether the ITGAM variant is also associated with other ADs. We evaluated case-control association between rs1143679 and ADs (N=18,457) including primary Sjögren's syndrome, systemic sclerosis, multiple sclerosis, rheumatoid arthritis, juvenile idiopathic arthritis, celiac disease, and type-1 diabetes. We also performed meta-analyses using our data in addition to available published data. Although the risk allele 'A' is relatively more frequent among cases for each disease, it was not significantly associated with any other ADs tested in this study. However, the meta-analysis for systemic sclerosis was associated with rs1143679 (p(meta)=0.008). In summary, this study explored the role of ITGAM in general autoimmunity in seven non-lupus ADs, and only found association for systemic sclerosis when our results were combined with published results. Thus ITGAM may not be a general autoimmunity gene but this variant may be specifically associated with SLE and systemic sclerosis.
authors.affiliation: Center for Autoimmune Diseases Research (CREA), Universidad del Rosario, Bogotá, Colombia.
authors.forename: Juan-Manuel
authors.initials: JM
authors.lastname: Anaya
authors.forename: Xana
authors.initials: X
authors.lastname: Kim-Howard
authors.forename: Sampath
authors.initials: S
authors.lastname: Prahalad
authors.forename: Alejandra
authors.initials: A
authors.lastname: Cherñavsky
authors.forename: Carlos
authors.initials: C
authors.lastname: Cañas
authors.forename: Adriana
authors.initials: A
authors.lastname: Rojas-Villarraga
authors.forename: John
authors.initials: J
authors.lastname: Bohnsack
authors.forename: Roland
authors.initials: R
authors.lastname: Jonsson
authors.forename: Anne Isine
authors.initials: AI
authors.lastname: Bolstad
authors.forename: Johan G
authors.initials: JG
authors.lastname: Brun
authors.forename: Beth
authors.initials: B
authors.lastname: Cobb
authors.forename: Kathy L
authors.initials: KL
authors.lastname: Moser
authors.forename: Judith A
authors.initials: JA
authors.lastname: James
authors.forename: John B
authors.initials: JB
authors.lastname: Harley
authors.forename: Swapan K
authors.initials: SK
authors.lastname: Nath
mesh_terms: D001327:Autoimmune Diseases / Q000453:epidemiology / Q000235:genetics*; D039481:CD11b Antigen / Q000235:genetics*; D004252:DNA Mutational Analysis; D005060:Europe; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007843:Latin America; D020641:Polymorphism, Single Nucleotide
chemical_list: D039481:CD11b Antigen; C509295:ITGAM protein, human