Some of them influence the serum concentrations of L-ficolin (e.g., rs17514136 and rs3124953), while others are associated with the risk of various diseases, such as systemic lupus erythematosus (SLE), schistosomiasis or Chagas disease [11,12,13,14,15,16]. The gene discussed is FCN2; the disease is systemic lupus erythematosus.