As for the antagonizing effect of C proteins against IFN responses through a Jak/STAT pathway, infection of all of the SeV recombinants, Cm2′, Cm3′, Cm4′, and Cm*, containing substitutions of the charged amino acid residues had lost their counteraction against induction of an antiviral state triggered by IFN-α treatment, suggesting that K77, D80, E114, E115, D142, K151, E153, and R157 within the C proteins are all important for this function. The gene discussed is IFNA1; the disease is infection.