She was hospitalized for the management of nephrotic syndrome and was found to be ANA negative with a decreased C1q complement of 94 (102–171 mg/L), but was negative for other SLE autoantibodies (anti-Smith and anti-dsDNA) and had normal C3 (101 mg/dL, reference range 90–180 mg/dl) and C4 complement (33 mg/dl, reference range 10–40 mg/dL). This evidence concerns the gene C3 and systemic lupus erythematosus.