Abstract

Objective: To determine whether c.843+7G>A Gas6 polymorphism is related to the development of systemic lupus erythematosus (SLE) and to investigate the association of its plasma level with different clinical manifestations and disease activity in SLE. Methods: This study was conducted on 50 SLE patients together with 40 age and sex matched apparently healthy volunteers. Disease activity was defined by SLE Disease Activity Index (SLEDAI) score. The Gas6 protein was measured in serum using a commercially available ELISA kit and Gas6 gene polymorphism by polymerase chain reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). Results: The GAS6 c.834+7 GG genotype was associated with an increased risk for SLE (GG vs. GA (OR; 3.4; 95% CI 1.2–9.5); and GG vs. AA (OR 3.6, 95% CI 1.1–11.8)) with significant differences were observed among the 3 genotypes (P < 0.001). Serum Gas6 concentrations were higher among SLE patients (15.9±0.8) compared with healthy control subjects (13.2±0.9) (P<0.001) and correlated with markers of renal inflammation and SLEDAI score. Some statistically significant differences were observed between Gas6 c.843+7G>A polymorphisms (p<0.05) with arthritis and renal disorders. Conclusion: The GAS6 c.834+7 GG genotype could be a genetic determinant of SLE disease pathogenesis with special attention to lupus nephritis and could be used as a marker of disease activity.