Given that RIG-I and MDA5 can sense different dsRNA virus species in mammals (1), our results suggest that, when a certain RNA virus infection is sensed by both RIG-I and MDA5, it is possible that at the early stage of virus infection, LGP2 is expressed at low levels and thus mainly promotes MDA5 signaling to enhance host IFN response for virus clearance, and at the same time, LGP2 of low expression levels does not nearly inhibit RIG-I signaling. This evidence concerns the gene IFIH1 and viral infectious disease.