TGFB1 and Friedreich ataxia: First, renal circHIPK3 was upregulated, miR-30a was downregulated, and there was increased RNA expression of profibrotic genes, such as those encoding TGF-β1, FN, and COL1, in mice with FA-induced renal tubulointerstitial fibrosis and in renal biopsies from patients with cTIN.