Figure 2. Initiation of abnormal eye size in the IRBP KO mouse. To refine the point in time when the knockout (KO) eye begins to become larger and heavier than the wild-type (WT) mouse eye, we weighed mouse eyes daily from P5 to P10. Eye weight in the interphotoreceptor retinoid-binding protein (IRBP) KO mouse started to increase compared to the WT mouse at P7 (well before eye opening at P13–P14). This difference was significant at P8 and older (** represents p<0.01). Eye weights at earlier ages (P5 and P6) were the same in the WT and KO eyes. Sample numbers represent independent mice. Sample numbers at each age and strain are given on the figure. Error bars represent standard deviation.