The Ca2+ permeability (PCa/PCs; Fig. 7C,D) was reduced 7-fold relative to control from 4.25 ± 0.35 (N = 8) to 0.57 ± 0.04 (N = 7) in the homozygotes, Tmc1 p.D528N/D528N. This evidence concerns the gene TMC1 and posterior cortical atrophy.