Mutations in hepatocyte nuclear factor-1 beta and their related phenotypes

Background: Hepatocyte nuclear factor-1 beta (HNF-1 beta) is a widely distributed transcription factor which plays a critical role in embryonic development of the kidney, pancreas, liver, and Mullerian duct. Thirty HNF-1 beta mutations have been reported in patients with renal cysts and other renal developmental disorders, young-onset diabetes, pancreatic atrophy, abnormal liver function tests, and genital tract abnormalities. Methods: We sequenced the HNF-1 beta gene in 160 unrelated subjects with renal disease, 40% of whom had a personal/ family history of diabetes. Results: Twenty three different heterozygous HNF-1 beta mutations were identified in 23/160 subjects (14%), including 10 novel mutations (V61G, V110G, S148L, K156E, Q176X, R276Q, S281fsinsC, R295P, H324fsdelCA, Q470X). Seven (30%) cases were proven to be due to de novo mutations. Renal cysts were found in 19/23 (83%) patients ( four with glomerulocystic kidney disease, GCKD) and diabetes in 11/ 23 (48%, while three other families had a family history of diabetes. Only 26% of families met diagnostic criteria for maturity-onset diabetes of the young ( MODY) but 39% had renal cysts and diabetes (RCAD). We found no clear genotype/phenotype relationships. Conclusion: We report the largest series to date of HNF-1 beta mutations and confirm HNF-1 beta mutations as an important cause of renal disease. Despite the original description of HNF-1 beta as a MODY gene, a personal/ family history of diabetes is often absent and the most common clinical manifestation is renal cysts. Molecular genetic testing for HNF-1 beta mutations should be considered in patients with unexplained renal cysts ( including GCKD), especially when associated with diabetes, early-onset gout, or uterine abnormalities.