Results: The percentage of apoptotic cells in SLE patients was not different in comparison with controls (20.2% ± 1.4 vs 21.1% ± 1.0), but the expression levels of FasL, caspase 8, and caspase 9 genes in all SLE patients and in female patients were significantly lower than controls; 0.45R vs 0.78R for FasL, 0.74R vs 1.0R for caspase 8, and 0.76R vs 1.26R for caspase 9 in all SLE patients and 0.37R vs 0.82R for FasL, 0.45R vs 1.6R for caspase 8, and 0.63R vs 1.56R for caspase 9 in female patients. The gene discussed is FASLG; the disease is systemic lupus erythematosus.