Association of Tumor Necrosis Factor Alpha-Induced Protein 3 Interacting Protein 1 (TNIP1) Gene Polymorphism (rs7708392) with Lupus Nephritis in Egyptian Patients.

Lupus nephritis (LN) is a major cause of morbidity and mortality in systemic lupus erythematosus (SLE). Previous studies suggest that mutant A20 binding inhibitor of NF-κB 1 (ABIN1) protein encoded by tumor necrosis factor alpha-induced protein 3 interacting protein 1 (TNIP1) gene is associated with LN via NF-κB dysregulation. The aim of the current study was to evaluate the association of TNIP1 gene SNP rs7708392 with SLE and LN in Egyptian patients. 5' nuclease Allelic discrimination was used to evaluate the frequency of TNIP1 SNP rs7708392 in 53 patients with LN, 57 SLE patients without nephritis and 85 healthy controls. The genotyping analysis revealed that the CC genotype was more frequent in controls than SLE patients, while GC and GG genotypes were more common in SLE patients. Moreover, the GG genotype and the G allele were significantly more prevalent among LN patient than non-LN patients (P < 0.001). In LN patients, the most common genotype was GG (56.6%), while among the non-LN patients; the CG genotype was the most common (59.6%). Regression analysis demonstrated that SLE patients carrying only one G allele had a 3.4 folds increased risk for LN. Our results suggested that TNIP1 SNP (rs7708392) might be associated with the LN in Egyptian SLE patients. TNIP1 SNP (rs7708392) might be used to identify patients at risk of developing LN, which could help in early detection and treatment before progression to end-stage renal disease, improving patients' outcome and quality of life.