Frishberg et al. [2], Copelovitch et al. [13], and Fervenza [14] reported nephrotic-range proteinuria (NP) in patients with documented CLCN5 mutations and histological findings of focal segmental glomerulosclerosis (FSGS) or focal global glomerulosclerosis. Here, CLCN5 is linked to focal segmental glomerulosclerosis.