For analysis of SAC density and mosaic regularity, confocal z-stacks of ChAT-labeled SACs through the GCL and INL were acquired at similar locations in central retina. Sample sizes were 4-5 areas (0.099mm2) per animal, 2-4 animals per genotype. For each field, X-Y coordinates of SAC arrays were obtained by manually marking centers of cells using Fiji and used to compute SAC density (#/mm2), packing factor45, and Density recovery profiles (DRP)46 with WinDRP software (http://www.mpimf-heidelberg.mpg.de/~teuler/WinDRP/ReadMe.htm).
