Immune-Array Analysis in Sporadic Inclusion Body Myositis Reveals HLA-DRB1 Amino Acid Heterogeneity Across the Myositis Spectrum



Rothwell, Simon, Cooper, Robert G ORCID: 0000-0001-8337-9973, Lundberg, Ingrid E, Gregersen, Peter K, Hanna, Michael G, Machado, Pedro M, Herbert, Megan K, Pruijn, Ger JM, Lilleker, James B, Roberts, Mark
et al (show 22 more authors) (2017) Immune-Array Analysis in Sporadic Inclusion Body Myositis Reveals HLA-DRB1 Amino Acid Heterogeneity Across the Myositis Spectrum. ARTHRITIS & RHEUMATOLOGY, 69 (5). pp. 1090-1099.

Access the full-text of this item by clicking on the Open Access link.

Abstract

<h4>Objective</h4>Inclusion body myositis (IBM) is characterized by a combination of inflammatory and degenerative changes affecting muscle. While the primary cause of IBM is unknown, genetic factors may influence disease susceptibility. To determine genetic factors contributing to the etiology of IBM, we conducted the largest genetic association study of the disease to date, investigating immune-related genes using the Immunochip.<h4>Methods</h4>A total of 252 Caucasian patients with IBM were recruited from 11 countries through the Myositis Genetics Consortium and compared with 1,008 ethnically matched controls. Classic HLA alleles and amino acids were imputed using SNP2HLA.<h4>Results</h4>The HLA region was confirmed as the most strongly associated region in IBM (P = 3.58 × 10<sup>-33</sup> ). HLA imputation identified 3 independent associations (with HLA-DRB1*03:01, DRB1*01:01, and DRB1*13:01), although the strongest association was with amino acid positions 26 and 11 of the HLA-DRB1 molecule. No association with anti-cytosolic 5'-nucleotidase 1A-positive status was found independent of HLA-DRB1*03:01. There was no association of HLA genotypes with age at onset of IBM. Three non-HLA regions reached suggestive significance, including the chromosome 3 p21.31 region, an established risk locus for autoimmune disease, where a frameshift mutation in CCR5 is thought to be the causal variant.<h4>Conclusion</h4>This is the largest, most comprehensive genetic association study to date in IBM. The data confirm that HLA is the most strongly associated region and identifies novel amino acid associations that may explain the risk in this locus. These amino acid associations differentiate IBM from polymyositis and dermatomyositis and may determine properties of the peptide-binding groove, allowing it to preferentially bind autoantigenic peptides. A novel suggestive association within the chromosome 3 p21.31 region suggests a role for CCR5.

Item Type: Article
Uncontrolled Keywords: Myositis Genetics Consortium, Chromosomes, Human, Pair 3, Humans, Myositis, Inclusion Body, Genetic Predisposition to Disease, Receptors, CCR5, Autoantibodies, Age of Onset, Genetic Association Studies, HLA-DRB1 Chains, White People
Depositing User: Symplectic Admin
Date Deposited: 26 Sep 2017 10:12
Last Modified: 13 Feb 2023 23:13
DOI: 10.1002/art.40045
Open Access URL: http://10.0.3.234/art.40045
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3009641