Unilateral hypoplastic kidney - a novel highly penetrant feature of familial juvenile hyperuricaemic nephropathy
1 Department of Paediatric Nephrology, Bristol Royal Hospital for Children, Upper Maudlin Street, Bristol BS2 8BJ, UK
2 Academic Renal Unit, University of Bristol, Dorothy Hodgkin building level 1, Whitson Street, Bristol BS1 3NY, UK
3 Department of Molecular Genetics, Regional Molecular Genetics Laboratories, Addenbrooke’s Hospital, Cambridge CB2 0QQ, UK
4 Department of Paediatric Nephrology, University of Bristol, Bristol Royal Hospital for Children, Bristol BS2 8BJ, UK
BMC Nephrology 2014, 15:76 doi:10.1186/1471-2369-15-76Published: 9 May 2014
Familial juvenile hyperuricaemic nephropathy is a rare inherited nephropathy with genetic heterogeneity. Categorised by genetic defect, mutations in uromodulin (UMOD), renin (REN) and hepatocyte nuclear factor-1β (HNF-1β) genes as well as linkage to chromosome 2p22.1-21 have previously been identified. Knowledge of the genetics of this phenotype has provided important clues to developmental pathways in the kidney.
We report a novel phenotype, with the typical features of hyperuricemia and renal deterioration, but with the additional unexpected feature of unilateral renal hypoplasia. Mutation analyses of the existing known genes and genetic loci were negative indicating a new monogenic cause. Interestingly two cousins of the index case did not share the latter feature, suggesting a modifier gene effect.
Unilateral renal hypo/aplasia is usually sporadic and relatively common, with no genetic cause to date identified. This reported pedigree reveals the possibility that a new, unknown renal developmental gene may be implicated in the FJHN phenotype.