We also identified non-MHC epistatic interactions between RA susceptible loci LOC100506023 and IRF5 with Immunochip-wide significance (p < 1.1e-08) and between 2 neighboring single-nucleotide polymorphism near PTPN22 that were in low linkage disequilibrium with independent interaction (p < 1.0e-05).
Genome-wide association studies have established that the gene encoding the protein tyrosine phosphatase nonreceptor 22 (PTPN22) makes an important contribution to susceptibility to autoimmune disease, notably rheumatoid arthritis.
PTPN22 polymorphisms, but not R620W, were associated with the genetic susceptibility of systemic lupus erythematosus and rheumatoid arthritis in a Chinese Han population.
The autoimmune-associated genetic variant PTPN22R620W enhances neutrophil activation and function in patients with rheumatoid arthritis and healthy individuals.
A C-to-T single-nucleotide polymorphism (SNP) located at position 1858 of human protein tyrosine phosphatase PTPN22 complementary DNA carries the highest risk of rheumatoid arthritis (RA) among all non-HLA genetic variants.
ORs for associations with different HLA-DRB1 alleles, PTPN22 genotypes and smoking were calculated separately for each cohort as well as in meta-analysis in RA subsets defined by the presence/absence of anti-CarP and anticyclic citrullinated peptide (anti-CCP) antibodies.
A single nucleotide polymorphism of PTPN22, 1858C>T (rs2476601), disrupts an interaction motif in the protein, and is the most important non-HLA genetic risk factor for rheumatoid arthritis and the second most important for juvenile idiopathic arthritis.
The strong association of the R620W variant of the PTPN22 gene with RA in Caucasians was not replicated since this variant was monomorphic in our study, but other SNP variants of the PTPN22 gene were also not associated with RA in black South Africans, suggesting that this locus does not play a major role in RA in this population.
This work aimed at assessing the association of PTPN22 +1858 C>T gene polymorphism with the susceptibility, activity and severity of RA in Egyptian subjects.