IFITM1 and avian influenza: In order to examine the potential role of the avian IFITM genes in the global host response to avian influenza from LPAI and HPAI viruses the expression data (from duck) was clustered using CLUSTERGRAM (Fig. 6) and the functional profile of genes grouping with IFITM1, 2 and 3 were examined using DAVID and IPA (for details see Materials and Methods).