SNX9 expression and co-localization with podocin were significantly higher in specimens from patients with IgA nephropathy with poor prognosis (IgAN-poor), membranous nephropathy (MN) and focal segmental glomerulosclerosis (FSGS); these specimens are associated with severe podocyte injury compared with those from controls, patients with minimal change nephrotic syndrome (MCNS) and patients with IgA nephropathy with a good prognosis (IgAN-good; Fig. 6). Here, SNX9 is linked to focal segmental glomerulosclerosis.