IFNA1 and infection: Previous studies investigating ferret ISGs in the context of viral infections have been hampered by two main challenges: (i) the inability to determine which ferret ISGs are genuinely expressed during viral infection and (ii) the existence of multiple predicted transcript variants for each ISG in the NCBI database, with no indication of which isoform represents the major transcript produced during infection or in response to IFN stimulation [8, 29].