Since patients harbor one mutated and one WT allele, we co-expressed WT EGFP-SNAP25b with mutated EGFP-SNAP25b, by combining infection with separate viruses encoding WT and mutant protein in a 1:1 ratio, as done previously by others for Syt1 (Bradberry et al., 2020). The gene discussed is SYT1; the disease is infection.