The incomplete efficiency in infection and/or recombination (Figure 2G) caused a Sept7flox/flox/Sept7−/− mosaic culture and a heterogeneity in SEPT7 level after 12 days, which demonstrated that cells without SEPT7 expression were almost exclusively multinucleated and significantly larger than the neighboring mononucleated cells with residual SEPT7 (Figure 2H and Figure S3A, S3D). This evidence concerns the gene SEPTIN7 and infection.