1H, 13C and 15N backbone resonance assignments of hepatocyte nuclear factor-1-beta (HNF1β) POUS and POUHD

Hepatocyte nuclear factor 1β (HNF1β) is a transcription factor that plays a key role in the development and function of the liver, pancreas, and kidney. HNF1β plays a key role in early vertebrate development and the morphogenesis of these organs. In humans, heterozygous mutations in the HNF1B gene can result in organ dysplasia, making it the most common cause of developmental renal diseases, including renal cysts, renal malformations, and familial hypoplastic glomerular cystic kidney disease. Pathogenic variants in the HNF1B gene are known to cause various diseases, including maturity-onset diabetes of the young and developmental renal diseases. This study presents the backbone resonance assignments of HNF1β POUS and POUHD domains, which are highly conserved domains required for the recognition of double-stranded DNA. Our data will be useful for NMR studies to verify the altered structures and functions of mutant HNF1B proteins that can induce developmental renal diseases, including renal cysts, renal malformations, and familial hypoplastic glomerular cystic kidney disease. This study will provide the structural basis for future studies to elucidate the molecular mechanisms underlying how mutations in HNF1β cause diseases.

MODY5 and Serous Ovarian Carcinoma in 17q12 Recurrent Deletion Syndrome

Background/Objective

Maturity-onset diabetes of the young type 5 (MODY5) is caused by a hepatocyte nuclear factor 1β (HNF1β) gene mutation on chromosome 17q12. HNF1β mutations have also been found in ovarian clear cell carcinoma, whereas ovarian non-clear cell carcinoma expresses this mutation rarely. 17q12 recurrent deletion syndrome features include MODY5, urogenital anomalies, and psychiatric and neurodevelopmental disorders. This is a report of a patient with 17q12 recurrent deletion syndrome with MODY5, uterine abnormalities, and low-grade serous ovarian cancer.

Case Report

A 25-year-old woman with recently diagnosed stage IIIC low-grade serous ovarian carcinoma was evaluated at the endocrinology clinic for diabetes, which was diagnosed at the age of 12 years. C-peptide level was detectable and T1DM antibodies were negative. The mother had diabetes, partially septated uterus, and solitary kidney. Abdominal computed tomography showed pancreatic atrophy, ascites, omental and peritoneal nodularity, and calcifications. Laparoscopy revealed bicornuate uterus, 2 cervices, and vaginal septum. The patient underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy, lymph node dissection, and omentectomy. Chromosomal microarray analysis revealed a pathogenic ∼1.8 Mb loss of 17q12, denoted arr[hg19]17q12(34477479_36283807)x1.

Discussion

17q12deletion has been described as a susceptibility locus in some ovarian cancers. However, to our knowledge, predisposition to ovarian cancer as a feature of 17q12 recurrent deletion syndrome or MODY5 was not reported previously.

Conclusion

The disease association reported suggests that medical providers should periodically evaluate for ovarian cancer, gut, and urogenital abnormalities in individuals with MODY5. Likewise, individuals with diabetes plus urogenital tract abnormalities or 17q12deletion in an ovarian tumor should undergo genetic testing for MODY5.

Pregnancy outcome with maternal HNF1B gene mutations and 17q12 deletions

There is an increasing body of literature regarding monogenic diabetes, particularly the more common forms of glucokinase and HNF1-alpha mutations (MODY2 and MODY3). There is relatively little published literature regarding rarer mutations. HNF1-beta mutations and 17q12 deletions may be associated with a broad range of organ dysfunction, renal disease and diabetes in particular resulting in high-risk pregnancies. This manuscript describes pregnancy outcomes in a woman with an HNF1-beta mutation and 2 women with an HNF1B/17q12 deletion and reviews the previously published literature. It highlights the significant rate of adverse maternal and fetal outcomes, and the maternal features suggestive of the diagnosis which should be considered in preconception counselling.

A Case of Diabetes Mellitus Type MODY5 as a feature of 17q12 Deletion Syndrome

Maturity onset diabetes of the young (MODY) is characterized by noninsulin-dependent diabetes diagnosed at a young age (<25 years) with an autosomal dominant inheritence. Rare mutations in the hepatocyte nuclear factor-1-beta (HNF1B) gene produce a syndrome that resemble MODY and about half of patients diagnosed with MODY5 (HNF1B mutation) have a a whole gene deletion, called as 17q12 deletion syndrome, is a rare chromosomal anomaly and is typified by deletion of the more than 15 genes including HNF1B resulting in kidney abnormalities and renal cysts and diabetes syndrome and neurodevelepmental or neuropsychiatric disorders. A 12-year-old girl was referred to our clinic, after high blood sugar was detected in the hospital where she suffered with the complaints of poliuria and polydipsia for the last 1 month. Her serum magnessium level was low (1.5 mg/dl) (normal value 1.6-2.6) and HbA1c level was 14% (normal value 3.6-5.8) and c-peptide level was 1.54 ng/ml (normal value 0.8-4). MODY5 was suspected and followed NGS gene panel (ABCC8, BLK, CEL, GCK, HNF1A, HNF1B, HNF4A, INS, KCNJ11, KLF11, NEURODD1, PAX4, PDX1, RFX6, ZFP57, GLIS3, FOXP3, NEUROG3, G6PC2) analysis revealed that there was no any mutation. On follow-up period, her serum magnessium level was low (1.2 mg/dl) and her urinary magnessium excretion was high at 172.5 mg/day. HNF1B gene mutation was considered in the patient with chronic hypomagnesemia with increased basal C peptide level. Abdominal CT and MR imagings revealed that there was a 43 mm diameter cystic lesion in the head of the pancreas, and agenesis of the pancreatic neck, trunk and tail as well. Because of there is no mutation in HBF1B gene in NGS panel, microarray analysis was performed, heterozygous deletion at 17q12 including HNF1B was detected. The HNF1B mutation is difficult to diagnose and has a large phenotypic variation . In case of clinical suspicion,further genetic examination (MLPA, array CGH) may be required since deletions and duplications can not be detected even if mutations in the HNF1B gene are not detected with NGS.

MODY5 Hepatocyte Nuclear Factor 1ß (HNF1ß)-Associated Nephropathy: experience from a regional monogenic diabetes referral centre in Singapore

From our monogenic diabetes registry set-up at a secondary-care diabetes center, we identified a nontrivial subpopulation (~15%) of maturity-onset diabetes of the young (MODY) among people with young-onset diabetes. In this report, we describe the diagnostic caveats, clinical features and long-term renal-trajectory of people with HNF1B mutations (HNF1B-MODY). Between 2013 and 2020, we received 267 referrals to evaluate MODY from endocrinologists in both public and private practice. Every participant was subjected to a previously reported structured evaluation process, high-throughput nucleotide sequencing and gene-dosage analysis. Out of 40 individuals with confirmed MODY, 4 (10%) had HNF1B-MODY (harboring either a HNF1B whole-gene deletion or duplication). Postsequencing follow-up biochemical and radiological evaluations revealed the known HNF1B-MODY associated systemic-features, such as transaminitis and structural renal-lesions. These anomalies could have been missed without prior knowledge of the nucleotide-sequencing results. Interestingly, preliminary longitudinal observation (up to 15 years) suggested possibly 2 distinct patterns of renal-deterioration (albuminuric vs. nonalbuminuric chronic kidney disease). Monogenic diabetes like HNF1B-MODY may be missed among young-onset diabetes in a resource-limited routine-care clinic. Collaboration with a MODY-evaluation center may fill the care-gap. The long-term renal-trajectories of HNF1B-MODY will require further studies by dedicated registries and international consortium.

The Clinical Characteristics and Gene Mutations of Maturity-Onset Diabetes of the Young Type 5 in Sixty-One Patients

AIMS

Maturity-onset diabetes of the young type 5 (MODY5), a rare disease, is very easy to be misdiagnosed as type 2 diabetes. To get better understanding of the disease, we analyzed the clinical characteristics and gene mutations of MODY5.

METHODS

PubMed, Cochrane, the China National Knowledge Infrastructure, and Wanfang were searched with the following search terms: "MODY5" OR "HNF1B maturity-onset diabetes of the young" OR "maturity-onset diabetes of the young type 5" OR "renal cysts and diabetes syndrome". Clinical characteristics and gene mutations of MODY5 were analyzed. The demography, clinical characteristics, and blood indicators of patients were described utilizing simple summary statistics. Variables were analyzed by t-test, Wilcoxon signed rank test, and Fisher exact test. Spearman's correlation analysis was used for bi-variate analysis. All tests were two-sided, and a p-value < 0.05 was considered statistically significant. Statistical analysis was performed using the Statistical Package for the Social Sciences version 26 for Windows (SPSS).

RESULTS

A total of 48 literatures were included in this study, including 61 eligible patients and 4 different mutations. Of the 39 patients with available body weight index, 15 (38.46%) were underweight, 21 (53.85%) were normal weight and 3 (7.69%) were overweight or obese. Of the 38 patients with available family history, 25 (65.79%) reported a family history of diabetes. Of the 34 patients with available age of diabetes diagnosis, the median age of diabetes diagnosis was 16.00 years old and 88.24% (30/34) of patients were under 25 years old when they were first diagnosed with diabetes. Renal cysts were presented in 72.41%, hypomagnesemia in 91.67%, and pancreatic dysplasia in 71.88% of the patients. Patients with hepatocyte nuclear factor 1B (HNF1B) deletion had lower serum magnesium, serum creatinine, and higher eGFR than patients with other gene mutations, and the difference was statistically significant.

CONCLUSIONS

The young onset of diabetes with low or normal BMI, renal cysts, hypomagnesemia, and pancreatic dysplasia should be recommended to genetic testing in order to differentiate MODY5 from other types of diabetes earlier.

Case Report: A case of HNF1B mutation patient with first presentation of diabetic ketosis

BACKGROUND

Maturity-onset diabetes of the young 5 (MODY5), a rare diabetes syndrome of young adults, is associated with variants in hepatocyte nuclear factor 1B (HNF1B) gene.

CASE PRESENTATION

We reported a case of MODY5, which presented with diabetic ketosis, multiple renal cysts, and hypokalemia. In this case, the HNF1B score was estimated as 13 and a heterozygous variant of HNF1B in exon 4 (c.826C>T, p.Arg276*) was identified through Sanger sequencing.

CONCLUSIONS

Multiple renal cysts and youth-onset diabetes are common manifestations in patients with HNF1B mutations, and insufficient insulin secretion may be a potential cause of diabetic ketosis in MODY5.

A case of familial recurrent 17q12 microdeletion syndrome presenting with severe diabetic ketoacidosis

BACKGROUND

Heterozygous intragenic mutations of the hepatocyte nuclear factor 1 homeobox b gene (HNF1B) located on chromosome 17 and microdeletion of 17q12 region (17q12MD) leads to the complete loss of this gene, which causes renal cystic disease, diabetes mellitus (MODY5), hypomagnesemia, hyperuricemia, liver enzyme abnormalities, genital tract abnormalities and exocrine pancreatic insufficiency. In addition, patients with 17q12MD also have facial dysmorphism, neuro-developmental and neuropsychiatric disorders.

CASE

A 16-year-old girl with obesity and mild facial dysmorphism was admitted to the hospital with symptoms of diabetes that started two days prior to her admission. She was diagnosed with severe diabetic ketoacidosis and treated accordingly. She had been followed up with the diagnoses of multicystic renal disease, hydronephrosis, hepatosteatosis, hypomagnesemia and hyperuricemia since the age of six. She had mild intellectual disability. Her menarche started two months ago. Cranial magnetic resonance imaging revealed mild diffuse cerebral and cerebellar atrophy and a partial empty sella. Her mother had diabetes, hypomagnesemia and mild intellectual disability and her maternal grandfather and uncle had diabetes. Her grandfather also had renal cystic disease. All of them are on oral antidiabetic medication. The genetic analysis of the patient and her mother revealed a loss of 1.6 megabases in chromosome 17q12.

CONCLUSIONS

MODY5 should be kept in mind in patients with diabetes who present with extra pancreatic findings, especially with renal cystic disease, more over, a genetic analysis including the study of 17q12MD should be carried out in patients who present with additional neuropsychiatric findings. Ketoacidosis can be seen in patients with MODY5. Ketoacidosis and renal anomalies and dysfunction are factors that increase and affect the severity of each other in these patients.

Maturity-onset diabetes of the young (MODY) type 5, presenting as diabetic ketoacidosis with alkalemia - A report of a case

A 34-year-old man visited our hospital because of dry mouth and weight loss. His plasma glucose level was 32.8 mmol/L and serum levels of ketone bodies were increased, but with metabolic alkalemia. He was also suffering from renal tubular hypomagnesemia and hypokalemia. Abdominal CT revealed bilateral renal cysts. These findings were suggestive of maturity-onset diabetes of the young (MODY) type5. Genetic testing revealed heterozygous hepatocyte nuclear factor 1 beta (HNF1B) gene deletion. In the present case, it seemed reasonable to view HNF1B gene deletion as the common cause of MODY5-associated diabetic ketoacidosis and tubular malfunction-induced hypokalemic alkalosis. This case exemplifies an importance of HNF1B gene abnormality as a potential cause of diabetic ketoacidosis with alkalemia.

A case report with functional characterization of a HNF1B mutation (p.Leu168Pro) causing MODY5

We previously performed next-generation sequencing-based genetic screening in patients with autoantibody-negative type 1 diabetes, and identified the p.Leu168Pro mutation in HNF1B. Here,we report the clinical course of the patient and the results of functional characterization of this mutation. The proband had bilateral renal hypodysplasia and developed insulin-dependent diabetes during childhood. The pathogenicity of Leu168Pro-HNF1B was evaluated with three-dimensional structure modeling, Western blotting, immunofluorescence analysis and luciferase reporter assays using human embryonic kidney 293 cells. Three-dimensional structure modeling predicted that the Leu168 residue is buried in the DNA-binding Pit-Oct-Unc-specific (POU_S) domain and forms a hydrophobic core. Western blotting showed that the protein expression level of Leu168Pro-HNF1B was lower than that of wild-type (WT) HNF1B. Immunofluorescence staining showed that both WT- and Leu168Pro-HNF1B were normally localized in the nucleus. The cells transfected with WT-HNF1B exhibited 5-fold higher luciferase reporter activity than cells transfected with an empty vector. The luciferase activities were comparable between WT-HNF1B/Leu168Pro-HNF1B and WT-HNF1B/empty vector co-transfection. In conclusion, Leu168Pro is a protein-destabilizing HNF1B mutation, and the destabilization is likely due to the structural changes involving the hydrophobic core of POU_S. The disease-causing Leu168Pro HNF1B mutation is a loss-of-function mutation without a dominant-negative effect.

Modeling HNF1B-associated monogenic diabetes using human iPSCs reveals an early stage impairment of the pancreatic developmental program

Heterozygous mutations in HNF1B in humans result in a multisystem disorder, including pancreatic hypoplasia and diabetes mellitus. Here we used a well-controlled human induced pluripotent stem cell pancreatic differentiation model to elucidate the molecular mechanisms underlying HNF1B-associated diabetes. Our results show that lack of HNF1B blocks specification of pancreatic fate from the foregut progenitor (FP) stage, but HNF1B haploinsufficiency allows differentiation of multipotent pancreatic progenitor cells (MPCs) and insulin-secreting β-like cells. We show that HNF1B haploinsufficiency impairs cell proliferation in FPs and MPCs. This could be attributed to impaired induction of key pancreatic developmental genes, including SOX11, ROBO2, and additional TEAD1 target genes whose function is associated with MPC self-renewal. In this work we uncover an exhaustive list of potential HNF1B gene targets during human pancreas organogenesis whose downregulation might underlie HNF1B-associated diabetes onset in humans, thus providing an important resource to understand the pathogenesis of this disease.

Maturity-onset diabetes of the young type 5 a MULTISYSTEMIC disease: a CASE report of a novel mutation in the HNF1B gene and literature review

Background

Diabetes mellitus with autosomal dominant inheritance, such as maturity-onset diabetes of the young (MODY), is a genetic form of diabetes mellitus. MODY is a type of monogenic diabetes mellitus in which multiple genetic variants may cause an alteration to the functioning of beta cells. The three most known forms of MODY are caused by modifications to the hnf4a, gck, and hnf1a genes. However, other MODY variants can cause multiple alterations in the embryonic development of the endoderm. This is the case in patients presenting with MODY5, who have a mutation of the hepatic nuclear factor 1B (hnf1b) gene.

Case presentation

We present the clinical case of a 15 year-old patient with a family history of diabetes mellitus and a classical MODY type 5 (MODY5) phenotype involving the pancreas and kidney, with a novel, unreported mutation in the hnf1b gene.

Conclusions

MODY5 is characterised by a mutation in the hnf1b gene, which plays an important role in the development and function of multiple organs. It should be suspected in patients with unusual diabetes and multisystem involvement unrelated to diabetes.

Graphical abstract

A Novel p.L145Q Mutation in the HNF1B Gene in a Case of Maturity-onset Diabetes of the Young Type 5 (MODY5)

Maturity-onset diabetes of the young (MODY) is an autosomal dominant form of early onset diabetes. The hepatocyte nuclear factor-1-beta (HNF1B) gene is responsible for MODY type 5 (MODY5) with distinctive clinical features, including pancreatic atrophy and renal disease. We herein report a Japanese case of young-onset diabetes with typical phenotypes of MODY5 and a novel heterozygous missense mutation (p.L145Q) in the HNF1B gene. The mutation was located in the Pit-Oct-Unc (POU)-specific domain, and the amino acid residue L145 was highly conserved among species. It is strongly suggested that this mutation explains the phenotypes of MODY5.

Metabolic Profiling of Multiorgan Samples: Evaluation of MODY5/RCAD Mutant Mice

In the present study, we performed a metabolomics analysis to evaluate a MODY5/RCAD mouse mutant line as a potential model for HNF1B-associated diseases. Gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) of gut, kidney, liver, muscle, pancreas, and plasma samples uncovered the tissue specific metabolite distribution. Orthogonal projections to latent structures discriminant analysis (OPLS-DA) was used to identify the differences between MODY5/RCAD and wild-type mice in each of the tissues. The differences included, for example, increased levels of amino acids in the kidneys and reduced levels of fatty acids in the muscles of the MODY5/RCAD mice. Interestingly, campesterol was found in higher concentrations in the MODY5/RCAD mice, with a four-fold and three-fold increase in kidneys and pancreas, respectively. As expected, the MODY5/RCAD mice displayed signs of impaired renal function in addition to disturbed liver lipid metabolism, with increased lipid and fatty acid accumulation in the liver. From a metabolomics perspective, the MODY5/RCAD model was proven to display a metabolic pattern similar to what would be suspected in HNF1B-associated diseases. These findings were in line with the presumed outcome of the mutation based on the different anatomy and function of the tissues as well as the effect of the mutation on development.

Hnf1b controls pancreas morphogenesis and the generation of Ngn3+ endocrine progenitors

Heterozygous mutations in the human HNF1B gene are associated with maturity-onset diabetes of the young type 5 (MODY5) and pancreas hypoplasia. In mouse, Hnf1b heterozygous mutants do not exhibit any phenotype, whereas the homozygous deletion in the entire epiblast leads to pancreas agenesis associated with abnormal gut regionalization. Here, we examine the specific role of Hnf1b during pancreas development, using constitutive and inducible conditional inactivation approaches at key developmental stages. Hnf1b early deletion leads to a reduced pool of pancreatic multipotent progenitor cells (MPCs) due to decreased proliferation and increased apoptosis. Lack of Hnf1b either during the first or the secondary transitions is associated with cystic ducts. Ductal cells exhibit aberrant polarity and decreased expression of several cystic disease genes, some of which we identified as novel Hnf1b targets. Notably, we show that Glis3, a transcription factor involved in duct morphogenesis and endocrine cell development, is downstream Hnf1b. In addition, a loss and abnormal differentiation of acinar cells are observed. Strikingly, inactivation of Hnf1b at different time points results in the absence of Ngn3(+) endocrine precursors throughout embryogenesis. We further show that Hnf1b occupies novel Ngn3 putative regulatory sequences in vivo. Thus, Hnf1b plays a crucial role in the regulatory networks that control pancreatic MPC expansion, acinar cell identity, duct morphogenesis and generation of endocrine precursors. Our results uncover an unappreciated requirement of Hnf1b in endocrine cell specification and suggest a mechanistic explanation of diabetes onset in individuals with MODY5.

Bicaudal C1 promotes pancreatic NEUROG3+ endocrine progenitor differentiation and ductal morphogenesis

In human, mutations in bicaudal C1 (BICC1), an RNA binding protein, have been identified in patients with kidney dysplasia. Deletion of Bicc1 in mouse leads to left-right asymmetry randomization and renal cysts. Here, we show that BICC1 is also expressed in both the pancreatic progenitor cells that line the ducts during development, and in the ducts after birth, but not in differentiated endocrine or acinar cells. Genetic inactivation of Bicc1 leads to ductal cell over-proliferation and cyst formation. Transcriptome comparison between WT and Bicc1 KO pancreata, before the phenotype onset, reveals that PKD2 functions downstream of BICC1 in preventing cyst formation in the pancreas. Moreover, the analysis highlights immune cell infiltration and stromal reaction developing early in the pancreas of Bicc1 knockout mice. In addition to these functions in duct morphogenesis, BICC1 regulates NEUROG3(+) endocrine progenitor production. Its deletion leads to a late but sustained endocrine progenitor decrease, resulting in a 50% reduction of endocrine cells. We show that BICC1 functions downstream of ONECUT1 in the pathway controlling both NEUROG3(+) endocrine cell production and ductal morphogenesis, and suggest a new candidate gene for syndromes associating kidney dysplasia with pancreatic disorders, including diabetes.

Identification and molecular characterization of HNF1B gene mutations in Indian diabetic patients with renal abnormalities

Heterozygous mutations of the HNF1B gene (HNF1B-MODY or MODY5) are associated with a wide clinical spectrum of renal and extrarenal disease without clear genotype-phenotype correlation. In this study, we investigated the prevalence of HNF1B gene mutations in young Indian diabetic patients with various renal abnormalities. Fifty unrelated young diabetic patients, who also had renal abnormalities, were selected from the electronic records of a large diabetes centre in Chennai, in southern India. All patients were sequenced for HNF1B gene mutations. The whole or partial gene deletion was analyzed by MLPA. Functional characterization of the novel variant (Asn321Asp) was also performed using transcriptional activation and subcellular localization assays. We identified six different HNF1B gene mutations which included four previously reported (-67C>T, Arg165His, IVS2nt+2insT, Met1_Trp557del) and two novel variations (Asn321Asp, IVS3nt-4C>G). The functional study revealed that the novel variation Asn321Asp in both the heterozygous and homozygous state showed similar transcriptional activity, expression levels and normal transportation of protein to the nucleus similar to wild type, suggesting that it is not likely to be pathogenic. This is the first major study of HNF1B-MODY from India and shows that about 10% of young diabetic subjects with renal abnormalities seen at a tertiary diabetes centre harbor HNF1B gene mutations.

A description of a fetal syndrome associated with HNF1B mutation and a wide intrafamilial disease variability

MODY5, renal cysts, and diabetes syndrome are autosomal dominant entities caused by mutation in the HNF1B gene. Here we report two fetal siblings and their father who have a HNF1B missense mutation and describe the fetal phenotype associated with mutation in this gene. To the best of our knowledge two non-twin siblings with a missense mutation and a severe phenotype have not been reported previously.