TCF2 gene's mutation of autosomal dominant inheritance, encoding for the HNF-1 beta transcription factor, is associated with monogenic Mody5 diabetes, renal structural and urogenital abnormalities, and hepatic cholestasis. We have identified a family with HNF-1 beta gene's mutation, and very different phenotypic expression: renal abnormalities with cysts, nephrocalcinosis, polyuropolydipsic syndrome, Mody5 diabetes, genital malformations. Molecular analysis identified a mutation of exon 4 of the TCF2 gene. The coexistence in the same family of pleiomorphic renal malformations (cysts, renal agenesia or hypoplasia, renal failure) with Mody-type diabetes, with an autosomal inheritance must lead to the search for a mutation of TCF2, one of the most frequent genetic renal diseases.