Virally mediated overexpression of rhodopsin leads to retinal degeneration in C57Bl/6J mice. Reduction in ERG a-wave and b-wave amplitudes in eyes injected with AAV-Rho (white bars) compared with the uninjected contralateral eyes (black bars) over a time course of 6 mo after injection of virus (n = 7). For the a-wave amplitudes, ** p < 0.005 at 2, 3, and 6 mo postinjection. For b-wave amplitudes, * p < 0.05 at 1 mo and ** p < 0.005 at 2, 3, and 6 mo postinjection. (From Mao et al. 2011; reprinted, with permission, from Mary Ann Liebert, Inc. © 2011.)