(A) Cochlear whole-mount images from WT controls, Bth/+ controls, AAV2/9 replacement alone, AAV2/9 RNAi + replacement, AAV2/2 RNAi + replacement, and AAV2/2 RNAi + replacement w/WPRE. Cochleae were stained with Myo7a (red) for labeling hair cells. Scale bars represent 100 μm. White dashed boxes represent area of high-magnification image capture for cell counting and comparison of animals treated with viral vectors to Bth/+ controls. (B, C) Quantitative comparison of inner hair cell and outer hair cell survival among all treatment groups. Data are means ± SEM. N mice per experimental condition are indicated in parentheses. Statistical analyses are summarized in Tables S5 and S6. ****P < 0.0001; ***P < 0.001; **P < 0.01; and *P < 0.05.