ABCA4 and diabetic kidney disease: We and others have shown that glomerular accumulation of lipids, e.g., cholesterol, occurs in diabetic kidney disease (DKD)7–11, focal segmental glomerulosclerosis (FSGS)12–14, and Alport syndrome (AS)13 and is associated with downregulation of ATP-binding cassette transporter (ABCA1)-mediated cholesterol efflux.