Nevertheless, the slight differences in 2′-5′OAS1 gene expression between rTGEV-wt and rTGEV-Δ7 infections could not explain the enhanced nuclease activity observed during mutant virus infection (Figure 6B), as 2′-5′OAS1 mRNA level was even lower for rTGEV-Δ7 than for rTGEV-wt virus (Figure 6B). The gene discussed is OAS1; the disease is viral infectious disease.