Association between severe disease course and nephritis with Q222R polymorphism in DNAse I gene among lupus patients: An Argentine multicenter study

Abstract Objetives: Systemic lupus erythematosus is a multifactorial autoimmune disease and the glomerulonephritis is one of the most severe complications, which leads to severe persistent proteinuria, chronic renal failure, and end-stage renal disease. This multicenter study investigated the genetic associations of a non-synonymous single-nucleotide polymorphism in DNase I with the risk of lupus and its influence on development of nephropathy in an Argentinean population. Methods: Using the Polymerase chain reaction restriction fragment length polymorphism method, the Q222R (+2373A→G; Gln244Arg) DNase I polymorphism was studied in 156 systemic lupus erythematosus patients and 170 healthy controls. Results: Although no significant association between Q222R polymorphism and the risk of systemic lupus erythematosus was found, the presence of the A allele was associated with an increased risk for the development of nephropathy (p=0.019, Odd Ratio=2.196, 95 % confidence interval [1.135-4.247]) and a worse disease course [moderate disease course: p=0.006, Odd Ratio=3.250, 95% confidence interval (1.401-7.539); severe disease course: p=0.040, Odd Ratio=2.339, 95% confidence interval (1.040-5.260)]. Conclusions: A better understanding of the genetic basis of systemic lupus erythematosus will help in the development of new and more effectives strategies for the treatment of the disease in the future.