The V proteins of many paramyxoviruses, including parainfluenza virus 5 (PIV5, previously referred to as simian virus 5 or SV5; Chatziandreou et al., 2004) and MPRV, are able to reduce the induction of IFN in response to dsRNA or virus infection (Andrejeva et al., 2004; Childs et al., 2006; He et al., 2002; Poole et al., 2002; Wansley & Parks, 2002). Here, IFNA1 is linked to viral infectious disease.