Primate and rodent IFITM1, IFITM2 and IFITM3 have similar functions [2] , but do not form a monophyletic cluster (Fig. 3) , indicating that they do not share the most recent common ancestor (MRCA) and moreover suggesting convergent evolution of IFITM1, IFITM2 and IFITM3 in primates and rodents. Convergently evolved amino acids between primates and rodents were found in the C-terminus of IFITM2 and IFITM3 (data not shown), a crucial region for antiviral activity, supporting the association between viral infections and the evolution of IR-IFITM genes.