NGS analysis was performed using the Nephropathy Solution (NES) kit (Sophia Genetics, Lausanne, Switzerland) covering the coding regions of 44 most clinically relevant genes related to a broad range of nephropathies (AGXT, AQP2, ATP6V0A4, ATP6V1B1, AVPR2, BSND, CASR, CEP290, CLCN5, CLCNKB, COL4A3, COL4A4, COL4A5, CRB2, CTNS, CUBN, CYP24A1, DSTYK, EMP2, EYA1, FN1, FOXC1, GRHPR, HNF1b, KANK2, KCNJ1, LAMB2, NPHS2, NR3C2, OCRL, PAX2, PHEX, PKD1, PKD2, PKHD1, SIX1, SLC12A1, SLC12A3, SLC34A1, SLC4A1, SLC4A4, TTC21B, UMOD, WT1). This evidence concerns the gene TTC21B and kidney disorder.