Alterations in the refractive properties of lenses have previously been reported for some mouse lines lacking expression of specific proteins, including Lim2Gt/Gt, which develop central pulverulent cataracts; CP49−/−, which show subtle opacification; and Epha2−/−, which do not develop cataracts.11,14,18,19 The changes in refractive properties in Lim2Gt/Gt and Epha2−/− lenses affect certain regions of the lens.11,14 In CP49−/− lenses, both BVD and BVD variability are increased.19 In contrast, Cx46fs380 homozygous lenses had decreased BVD and had BVD variability similar to wild type. The gene discussed is BFSP2; the disease is cataract.