The adult kidney replaces its parenchyma in vivo in steady state and during regeneration by segment-specific clonal cell proliferation.To understand human adult kidney clonal cell growth, we derived tissue from human nephrectomies and performed limiting dilution to establish genuine clonal cultures from one single cell.Clonal efficiency of the human kidney was x%. Remarkably, a single renal cell could give rise to up to 3.3*10(6) cells. Phenotypically, two types of clonal cultures were apparent; a stably proliferating cuboidal epithelial-like appearing (EL) and a rapidly proliferating fibroblast-like appearing (FL). RNA sequencing of all clonal cultures separated FL from EL cultures according to proximal-distal/collecting renal epithelial tubular identity, respectively. Moreover, distinct molecular features in respect to cellcycle, epithelial-mesenchymal transition, oxidative phosphorylation, BMP signaling pathway and cell surface markers were observed for each clone type. Surprisingly, clonal expansion (>3 months) was sustained in EL clones harboring markers of mature kidney epithelia (high CD24, CDH1, EpCAM, EMA) in contrast to dedifferentiated FL clones (high NCAM1, serpine1), which showed fast lineage amplification and exhausted in a few weeks. Thus, the human adult kidney harbors progenitor cell function in which segment identity and the level of epithelial differentiation dictate clonal characteristics.2 4 . Liu, J., et al., Loss of SETD2 Induces a Metabolic Switch in Renal Cell Carcinoma Cell Lines toward Enhanced Oxidative Phosphorylation . J Proteome Res, 2019. 18(1): p. 331-340.2 5 . , L., et al., Clear Cell Renal Cell Carcinoma is linked to Epithelial-to-Mesenchymal Transition and to Fibrosis. Physiol Rep, 2017. 5(11.( 2 6 . Sanchez, D.J. and M.C. Simon, Genetic and metabolic hallmarks of clear cell renal cell carcinoma. Biochim Biophys Acta Rev Cancer, 2018. 1870(1): p. 23-31. Landolt2 7 .Buzhor, E., et al., Cell-based therapy approaches: the hope for incurable diseases. Regen Med, 2014. 9(5): p. 649-72. 2 8 . Chuang, C.H., et al., Molecular definition of a metastatic lung cancer state reveals a targetable CD109-Janus kinase-Stat axis. Nat Med, 2017. 23(3): p. 291-300.