SIRT6 and kidney disorder: We first confirmed the reduction of Sirt6 in renal biopsies from DN (n = 8) and FSGS (n = 10) subjects compared with normal subjects or diabetic patients without nephropathy (DM-NN, n = 7) by immunohistochemistry (IHC) staining (Fig. 2a) and real time reverse transcription (RT)-PCR analysis (Fig. 2b).