Abbreviations: ESRD = end-stage renal disease, FSGS = focal segmental glomerulosclerosis, NPC = nuclear pore complex, NS = nephrotic syndrome, NUP93 = Nucleoporin 93, NUPs = nucleoporins, SRNS = steroid-resistant nephrotic syndrome, SSNS = steroid-sensitive nephrotic syndrome. The gene discussed is NPC1; the disease is focal segmental glomerulosclerosis.