We used half of the amount of viral infection units to reduce the expression to approximately the same levels as in the titration experiments in the Syt1+/+ neurons (Fig. 8A; VGLUT1 norm.: Syt1+/− 1 ± 0.08, n = 20/3, Syt1+/−1xRNA(Syt1) 1.2 ± 0.16, n = 17/3, p = n.s., and Syt1+/−2xRNA(Syt1) 0.93 ± 0.14, n = 15/3, p = n.s.; SYT1/VGLUT1 norm.: Syt1+/− 1 ± 0.07, n = 20/3, Syt1+/−1xRNA(Syt1) 0.32 ±0 .03, n = 17/3, p < 0.0001, and Syt1+/−2xRNA(Syt1) 0.22 ± 0.02, n = 15/3, p < 0.0001; Kruskal–Wallis test). This evidence concerns the gene SYT1 and viral infectious disease.