Restoration of cone-mediated optomotor behavior in Gucy2e–/– treated eyes. Shown is the photopic visual acuity and contrast sensitivity measurements in two untreated Gucy2e–/– mice (animals 1 and 2), and six mice treated with high-titer vector (animals 3–8) 4 months post treatment. Results are presented for each animal and averaged per group in the right-hand graphs. (a) Robust improvement in visual acuity was consistently observed in treated eyes (p<0.0001, one-way ANOVA). (b) A significant improvement in contrast sensitivity was detected in treated eyes (p<0.05, one-way ANOVA). OD, right eye; OS, left eye.