Clinical manifestations and laboratory indicators, such as erythrocyte sedimentation rate, C-reactive protein (CRP), complement C3, complement C4, antinuclear antibodies, double-stranded DNA, proteinuria, and hematuria, were examined to analyze the relationship between these indicators and the CDC27 expression in SLE patient PBMCs. The gene discussed is C3; the disease is systemic lupus erythematosus.