T-1237C polymorphism of TLR9 gene is not associated with multiple sclerosis in the Portuguese population

Toll-Like Receptors Gene Polymorphisms in Autoimmune Disease

Toll-like receptors (TLRs) are important initiators of the immune response, both innate and acquired. Evidence suggests that gene polymorphisms within TLRs cause malfunctions of certain key TLR-related signaling pathways, which subsequently increases the risk of autoimmune diseases. We illustrate and discuss the current findings on the role of Toll-like receptor gene polymorphisms in numerous autoimmune diseases in this review, such as type 1 diabetes mellitus, Graves’ disease, rheumatoid arthritis, systemic lupus erythematosus and multiple sclerosis. The study of genetic variation in TLRs in different populations has shown a complex interaction between immunity and environmental factors. This interaction suggests that TLR polymorphisms affect the susceptibility to autoimmune diseases differently in various populations. The identification of Toll-like receptor gene polymorphisms can expand our understanding of the pathogenesis of autoimmune diseases, which will subsequently guide effective medical management and provide insight into prognosis and advanced treatments.

The investigation of toll-like receptor 3, 9 and 10 gene polymorphisms in Turkish rheumatoid arthritis patients

Toll-like receptors (TLRs) play an important role in the induction and regulation of the innate immune system or adaptive immune responses. Genetic variations within human TLRs have been reported to be associated with a range of immune-related diseases. This study was conducted to investigate the frequencies of TLR3 rs3775290, TLR9 rs187084, and TLR10 rs4129009 polymorphisms and to detect between polymorphisms and autoantibody positive as RF, collagen type II, anti-RNP, and anti-CCP in patient group. We performed a case-control study of 100 rheumatoid arthritis (RA) cases and 100 healthy controls matched on age, sex, and residence. All polymorphisms in TLRs were determined by polymerase chain reaction-based restriction fragment length polymorphism. Serum autoantibody level was measured using quantitative ELISA. SNPs were genotyped in all samples. Our results showed that TT genotype for SNP 1237 T/C increased the RA risk significantly (p < 0.05). No statistically significant differences were found in the TLR3 and TLR10 genotypes or allele distribution between RA patients and control individuals. No associations were noted with autoantibody production and TLR3, TLR9, and TLR10 polymorphisms genotypes (p > 0.05). Our study suggests that a single nucleotide polymorphism (rs187084) in TLR9 gene may be a susceptibility factor for RA in Turkish population. Further studies are required to explore the role of TLRs gene polymorphisms in the risk of RA, especially in ethnically different populations to confirm our results.

Multiple sclerosis and polymorphisms of innate pattern recognition receptors TLR1-10, NOD1-2, DDX58, and IFIH1

Genetic factors are critical in multiple sclerosis (MS), and it is conceivable that the pattern recognition receptors of the innate immune system are of pathogenic importance. We therefore developed two novel assays capable of analyzing 42 single-nucleotide polymorphisms in the human genes encoding TLR1-10, NOD1-2, DDX58, and IFIH1. Using these assays, we genotyped 963 MS patients and 960 controls, and analyzed for possible associations to MS diagnosis, clinical course, severity, and age at onset. Our results support previous findings of associations between the IFIH1-locus and MS (IFIH1-rs3747517 and IFIH1-rs1990760 trend test: P=0.002 and P=0.014, respectively).