PKD2 and Huntington disease: Next, to quantify the efficiency of nephron formation between HC and HD groups, we performed qRT-PCR for representative nephron markers: NPHS1 and NPHS2 as terminally differentiated podocyte-specific markers; low density lipoprotein-related protein 2 (LRP2) as proximal tubule marker; solute carrier family 12 member 1 (SLC12A1) as loop of Henle marker; polycystin 1 (PKD1) and polycystin 2 (PKD2) as distal tubule markers.