In teleost fish, CFI genes from Ictalurus punctatus [22], Pelteobagrus vachellii [23], Cynoglossus semilaevis [24], Oncorhynchus mykiss [25], Paralichthys olivaceus [26] and Cyprinus carpio [27] have been identified, and structural information and the mRNA expression profiles during pathogen infection are revealed in these studies. This evidence concerns the gene CFI and infection.