Fig. 3. Quantification of retinal cells of the mutant retina. (A) The cell number was counted in a section (16 µm thick, 500 µm wide) of the central region of at least three independent samples from each genotype. The number of the ONL cells is reduced in NeuroD^–/– and Math3^–/–/NeuroD^–/– retina. The absolute numbers of the GCL and INL cells are not significantly affected by mutations. (B) Ratios of ganglion and amacrine cells in the GCL. The percentage of calbindin-positive and Thy1.2-positive cells per the total GCL cells was calculated. About a half of the GCL cells are amacrine cells in wild-type, Math3^–/– and NeuroD^–/– retina. By contrast, there are no amacrine cells (asterisk) in the GCL of Math3^–/–/NeuroD^–/– retina. As the absolute number of the GCL cells is not affected (A), these data indicate that the absolute number of ganglion cells is increased in Math3^–/–/NeuroD^–/– retina. (C) Ratios of cells in the INL. The cell number was counted as above, and the percentage of each retinal cell type per the total INL cells was calculated. There are ectopic ganglion cells but no amacrine cells (asterisk) in Math3^–/–/NeuroD^–/– INL.