Deoxyribonuclease I gene polymorphism and susceptibility to systemic lupus erythematosus.

The DNASE1 gene is regarded as one of the susceptible genes for systemic lupus erythematosus (SLE). Recent studies have detected the presence of a variable number of tandem repeat (VNTR) polymorphisms at intron 4 in this gene. The current study aimed to investigate the influence of current polymorphism on SLE susceptibility in a sample of the Iranian population. The study included 163 patients and 180 unrelated healthy controls. The VNTR polymorphisms in the DNASE1 gene were determined by polymerase chain reaction (PCR). The genotypic frequency investigation indicated that 3/6 genotype frequency in patients affected with SLE was more than healthy controls (P = 0.004). Moreover, 3/4 and 4/6 genotype frequencies in healthy cohort were further in comparison with patient cohort (P = 0.0001). Findings of the present study manifested that 3/6 genotype in patients affected with SLE was significantly more than healthy controls, thus it can be regarded as a risk factor, while 3/4 and 4/6 genotypes were significantly higher in healthy controls which can be considered as a protective factor.