rs4963128

This review article by Ota and Kuwana synthesizes genetic studies on systemic sclerosis (SSc), a complex autoimmune disease. Multiple genetic association studies, including GWAS and candidate gene approaches, have identified SSc susceptibility genes primarily involved in innate immunity (IRF4, IRF5, IRF7, IRF8, TNFAIP3), adaptive immune response (TNFSF4, CD247, PTPN22, CSK, STAT4, BLK), IL-12 signaling (IL-12A, IL-12RB1, IL-12RB2, TYK2), apoptosis/autophagy (ATG5, GSDMA, GSDMB, NOTCH4), and vascular homeostasis/fibrosis (PPARG). The review emphasizes that identified risk variants are predominantly located in non-coding regulatory regions and influence gene expression rather than protein structure.

This study identified rs1131665 (Q412R), a nonsynonymous SNP in IRF7, as associated with systemic lupus erythematosus (SLE) across multiple ethnic groups (Asian, European American, and African American populations; meta-analysis P = 6.18×10⁻⁶, OR = 1.42 [1.22–1.65]). Functional analysis demonstrated that the risk allele (412Q) resulted in a 2-fold increase in ISRE transcriptional activity, suggesting elevated IRF7 activation confers SLE susceptibility through dysregulation of the type I interferon pathway.

This is a comprehensive review of genetic factors in systemic sclerosis (SSc), a complex autoimmune disease. The review synthesizes findings from candidate gene analysis and genome-wide association studies identifying numerous SNPs and genetic variants associated with SSc susceptibility, primarily in genes involved in innate immunity (IRF4, IRF5, IRF7, IRF8, TNFAIP3), adaptive immunity (TNFSF4, PTPN22, STAT4, BLK, PRDM1), and cell death pathways (ATG5, DNASE1L3, GSDMA/B, NOTCH4). HLA class II genes are associated with SSc-related autoantibodies rather than SSc itself, with DRB1 alleles carrying the FLEDR amino acid sequence critical for anti-topo I antibody responses.

This review updates knowledge on genetic factors in systemic sclerosis (SSc) susceptibility and disease expression. GWAS and candidate gene studies have identified multiple SSc-associated genetic variants primarily located in non-coding regions that influence gene expression through eQTL effects. Major risk genes include those involved in innate immunity (IRF4, IRF5, IRF7, IRF8, TNFAIP3), adaptive immune response (PTPN22, STAT4, TNFSF4, CD247), and cell death pathways (ATG5), while few genes directly involve fibrosis or vascular homeostasis. HLA class II genes associate with SSc-related autoantibodies rather than SSc itself. Multi-omics approaches are needed to characterize the complex molecular architecture and identify biomarkers.

This study of 492 SLE patients across three ancestry groups identified genetic variation at the IRF7/PHRF1 locus associated with autoantibody profiles and serum interferonα activity. The rs702966 C allele was associated with anti-dsDNA antibodies (OR=1.83, P=0.0069) in European and Hispanic Americans and with higher IFNα levels in anti-dsDNA-positive patients (P=4.1×10⁻⁵). The rs4963128 T allele was associated with anti-Sm antibodies (OR=1.95, P=0.0017) in African Americans and with increased IFNα levels in anti-Sm-positive African American patients (P=0.0012). These findings demonstrate autoantibody-dependent genetic effects on IFNα production through the endosomal TLR/IRF7 pathway in SLE pathogenesis.

This comprehensive review examines genetic associations in type I interferon-related signaling pathways across multiple autoimmune diseases. The authors review evidence linking dysregulated interferon alpha (IFNα) signaling to systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and other autoimmune conditions, identifying multiple susceptibility genes including IFIH1, IRF5, STAT4, TYK2, BLK, BANK1, FCGR2A, and TREX1 with well-replicated associations and functional relevance to IFN pathway dysfunction.

A meta-analysis of 4,107 type 2 diabetes cases and 5,187 controls from three GWA studies found no evidence that common variants altering circulating inflammatory protein levels (IL-18, IL-6R, CRP, IL1RN, PAI1, MIF) or variants predisposing to autoimmune diseases (type 1 diabetes, rheumatoid arthritis, Crohn's disease, celiac disease, multiple sclerosis, SLE) are associated with type 2 diabetes risk. For example, rs2250417 in IL18 showed OR=1.00 (95% CI 0.99-1.03) versus the expected OR of ~1.15 if inflammation were causal, suggesting inflammatory markers are likely secondary rather than causative in type 2 diabetes.