Since MBL is a key molecule in the innate host defense against bacterial infection, the authors postulated that MBL could be considered as a double-edged sword molecule in the physiopathology of RF and RHD, on one hand conferring protection against initial infection by rheumatogenic streptococci, but on the other hand eliciting inflammation and complement tissue damage in the chronic stage of the disease (167). The gene discussed is MBL2; the disease is infection.