IFNA1 and viral infectious disease: In general, the expression patterns of porcine IFN-ω genes liken to unconventional IFN subtypes such as IFN-ε/κ/δ than the IFN-α subtype in the constitutive situation (Figure 5A) (9, 13); however, the porcine IFN-ω genes showed their own pattern of induced expression during viral infection.