SLE patients with renal involvement had elevated ficolin-1 (p = 0.009) levels, while those with hematological manifestations had a significantly reduced MASP-1 (p = 0.018), MASP-3 (p = 0.002), and MAp44 (p = 0.002) levels. This evidence concerns the gene MASP1 and systemic lupus erythematosus.