1
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Cornec-Le Gall E, Mallett AJ. Genomics in the kidney transplant clinic: the future standard of care? Kidney Int 2024; 106:18-20. [PMID: 38906652 DOI: 10.1016/j.kint.2024.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 05/06/2024] [Accepted: 05/08/2024] [Indexed: 06/23/2024]
Abstract
New evidence indicates potential benefit of genomics to illuminate nonkidney monogenic morbidity and mortality risk among kidney transplant recipients. This might be of direct relevance to an equivalent proportion of patients to those who harbor a monogenic kidney disease. Further evidence and replication are indicated, including a broadening potential range of monogenic and polygenic opportunities to improve clinical outcomes. Implementation will require such information, although it holds great promise.
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Affiliation(s)
- Emilie Cornec-Le Gall
- University of Brest, Inserm, Unité Mixte de Recherche (UMR) 1078, Génétique, Génomique fonctionnelle et Biotechnologies (GGB), Brest, France; Centre Hospitalier Universitaire (CHU) Brest, Service de Néphrologie, Centre de Référence Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Brest, France.
| | - Andrew J Mallett
- Department of Renal Medicine, Townsville University Hospital, Douglas, Queensland, Australia; College of Medicine and Dentistry, James Cook University, Douglas, Queensland, Australia; Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia.
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2
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Ali H, Malik MZ, Abu-Farha M, Abubaker J, Cherian P, Nizam R, Jacob S, Bahbahani Y, Naim M, Ahmad S, Al-Sayegh M, Thanaraj TA, Ong ACM, Harris PC, Al-Mulla F. Global analysis of urinary extracellular vesicle small RNAs in autosomal dominant polycystic kidney disease. J Gene Med 2024; 26:e3674. [PMID: 38404150 DOI: 10.1002/jgm.3674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/15/2024] [Accepted: 01/26/2024] [Indexed: 02/27/2024] Open
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent monogenic renal disease progressing to end-stage renal disease. There is a pressing need for the identification of early ADPKD biomarkers to enable timely intervention and the development of effective therapeutic approaches. Here, we profiled human urinary extracellular vesicles small RNAs by small RNA sequencing in patients with ADPKD and compared their differential expression considering healthy control individuals to identify dysregulated small RNAs and analyze downstream interaction to gain insight about molecular pathophysiology. METHODS This is a cross-sectional study where urine samples were collected from a total of 23 PKD1-ADPKD patients and 28 healthy individuals. Urinary extracellular vesicles were purified, and small RNA was isolated and sequenced. Differentially expressed Small RNA were identified and functional enrichment analysis of the critical miRNAs was performed to identify driver genes and affected pathways. RESULTS miR-320b, miR-320c, miR-146a-5p, miR-199b-3p, miR-671-5p, miR-1246, miR-8485, miR-3656, has_piR_020497, has_piR_020496 and has_piR_016271 were significantly upregulated in ADPKD patient urine extracellular vesicles and miRNA-29c was significantly downregulated. Five 'driver' target genes (FBRS, EDC3, FMNL3, CTNNBIP1 and KMT2A) were identified. CONCLUSIONS The findings of the present study make significant contributions to the understanding of ADPKD pathogenesis and to the identification of novel biomarkers and potential drug targets aimed at slowing disease progression in ADPKD.
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Affiliation(s)
- Hamad Ali
- Department of Medical Laboratory Sciences, Faculty of Allied Health Sciences, Health Sciences Center (HSC), Kuwait University, Jabriya, Kuwait
- Department of Genetics and Bioinformatics, Dasman Diabetes Institute (DDI), Dasman, Kuwait
- Division of Nephrology, Mubarak Al-Kabeer Hospital, Ministry of Health, Jabriya, Kuwait
| | - Md Zubbair Malik
- Department of Genetics and Bioinformatics, Dasman Diabetes Institute (DDI), Dasman, Kuwait
| | - Mohamed Abu-Farha
- Department of Biochemistry and Molecular Biology, Dasman Diabetes Institute (DDI), Dasman, Kuwait
| | - Jehad Abubaker
- Department of Biochemistry and Molecular Biology, Dasman Diabetes Institute (DDI), Dasman, Kuwait
| | - Preethi Cherian
- Department of Biochemistry and Molecular Biology, Dasman Diabetes Institute (DDI), Dasman, Kuwait
| | - Rasheeba Nizam
- Department of Genetics and Bioinformatics, Dasman Diabetes Institute (DDI), Dasman, Kuwait
| | - Sindhu Jacob
- Department of Genetics and Bioinformatics, Dasman Diabetes Institute (DDI), Dasman, Kuwait
| | - Yousif Bahbahani
- Division of Nephrology, Mubarak Al-Kabeer Hospital, Ministry of Health, Jabriya, Kuwait
- Medical Division, Dasman Diabetes Institute (DDI), Dasman, Kuwait
| | - Medhat Naim
- Division of Nephrology, Mubarak Al-Kabeer Hospital, Ministry of Health, Jabriya, Kuwait
| | - Sajjad Ahmad
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Mohammad Al-Sayegh
- Biology Division, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | | | - Albert C M Ong
- Academic Nephrology Unit, Division of Clinical Medicine, School of Medicine and Population Health, Faculty of Health, University of Sheffield, Sheffield, UK
| | - Peter C Harris
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Fahd Al-Mulla
- Department of Translational Medicine, Dasman Diabetes Institute (DDI), Dasman, Kuwait
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3
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Mariniello M, Schiano G, Yoshifuji A, Gillion V, Sayer JA, Jouret F, Le Meur Y, Cornec-Le Gall E, Olinger EG, Devuyst O. Uromodulin processing in DNAJB11-kidney disease. Kidney Int 2024; 105:376-380. [PMID: 38016513 DOI: 10.1016/j.kint.2023.11.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 10/04/2023] [Accepted: 11/10/2023] [Indexed: 11/30/2023]
Affiliation(s)
- Marta Mariniello
- Mechanisms of Inherited Kidney Disorders, Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Guglielmo Schiano
- Mechanisms of Inherited Kidney Disorders, Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Ayumi Yoshifuji
- Mechanisms of Inherited Kidney Disorders, Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Valentine Gillion
- Department of Nephrology, Cliniques Universitaires Saint-Luc, UCLouvain, Brussels, Belgium
| | - John Andrew Sayer
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK; Renal Services, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Freeman Road, Newcastle upon Tyne, UK
| | | | - Yannick Le Meur
- University of Brest, Unité Mixte de Recherche 1227, Centre Hospitalier Universitaire Brest, Brest, France
| | - Emilie Cornec-Le Gall
- University of Brest, Inserm, Unité Mixte de Recherche 1078, Génétique, Génomique fonctionnelle et Biotechnologies, Centre Hospitalier Universitaire Brest, Brest, France
| | - Eric Gregory Olinger
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK; Center for Human Genetics, Cliniques Universitaires Saint-Luc, UCLouvain, Brussels, Belgium
| | - Olivier Devuyst
- Mechanisms of Inherited Kidney Disorders, Institute of Physiology, University of Zurich, Zurich, Switzerland; Department of Nephrology, Cliniques Universitaires Saint-Luc, UCLouvain, Brussels, Belgium.
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Aiello V, Ciurli F, Conti A, Cristalli CP, Lerario S, Montanari F, Sciascia N, Vischini G, Fabbrizio B, Di Costanzo R, Olivucci G, Pietra A, Lopez A, Zambianchi L, La Manna G, Capelli I. DNAJB11 Mutation in ADPKD Patients: Clinical Characteristics in a Monocentric Cohort. Genes (Basel) 2023; 15:3. [PMID: 38275584 PMCID: PMC10815778 DOI: 10.3390/genes15010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/14/2023] [Accepted: 12/15/2023] [Indexed: 01/27/2024] Open
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a late-onset cilia-related disorder, characterized by progressive cystic enlargement of the kidneys. It is genetically heterogeneous with PKD1 and PKD2 pathogenic variants identified in approximately 78% and 15% of families, respectively. More recently, additional ADPKD genes, such as DNAJB11, have been identified and included in the diagnostic routine test for renal cystic diseases. However, despite recent progress in ADPKD molecular approach, approximately ~7% of ADPKD-affected families remain genetically unresolved. We collected a cohort of 4 families from our center, harboring heterozygous variants in the DNAJB11 gene along with clinical and imaging findings consistent with previously reported features in DNAJB11 mutated patients. Mutations were identified as likely pathogenetic (LP) in three families and as variants of uncertain significance (VUS) in the remaining one. One patient underwent to kidney biopsy and showed a prevalence of interstitial fibrosis that could be observed in ~60% of the sample. The presence in the four families from our cohort of ADPKD characteristics together with ADTKD features, such as hyperuricemia, diabetes, and chronic interstitial fibrosis, supports the definition of DNAJB11 phenotype as an overlap disease between these two entities, as originally suggested by the literature.
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Affiliation(s)
- Valeria Aiello
- Nephrology, Dialysis and Kidney Transplant Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (V.A.); (F.C.); (G.V.); (R.D.C.); (I.C.)
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (S.L.); (G.O.); (A.P.)
| | - Francesca Ciurli
- Nephrology, Dialysis and Kidney Transplant Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (V.A.); (F.C.); (G.V.); (R.D.C.); (I.C.)
| | - Amalia Conti
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.C.); (C.P.C.); (F.M.)
| | - Carlotta Pia Cristalli
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.C.); (C.P.C.); (F.M.)
| | - Sarah Lerario
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (S.L.); (G.O.); (A.P.)
| | - Francesca Montanari
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.C.); (C.P.C.); (F.M.)
| | - Nicola Sciascia
- Pediatric and Adult CardioThoracic and Vascular, Oncohematologic and Emergency Radiology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy;
| | - Gisella Vischini
- Nephrology, Dialysis and Kidney Transplant Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (V.A.); (F.C.); (G.V.); (R.D.C.); (I.C.)
| | - Benedetta Fabbrizio
- Pathology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy;
| | - Roberta Di Costanzo
- Nephrology, Dialysis and Kidney Transplant Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (V.A.); (F.C.); (G.V.); (R.D.C.); (I.C.)
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (S.L.); (G.O.); (A.P.)
| | - Giulia Olivucci
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (S.L.); (G.O.); (A.P.)
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.C.); (C.P.C.); (F.M.)
| | - Andrea Pietra
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (S.L.); (G.O.); (A.P.)
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.C.); (C.P.C.); (F.M.)
| | - Antonia Lopez
- Nephrology, Dialysis, Hypertension Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy;
| | - Loretta Zambianchi
- Nephrology and Dialysis, Ospedale Nuovo Morgagni-Forlì, 47120 Forlì, Italy;
| | - Gaetano La Manna
- Nephrology, Dialysis and Kidney Transplant Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (V.A.); (F.C.); (G.V.); (R.D.C.); (I.C.)
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (S.L.); (G.O.); (A.P.)
| | - Irene Capelli
- Nephrology, Dialysis and Kidney Transplant Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (V.A.); (F.C.); (G.V.); (R.D.C.); (I.C.)
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy; (S.L.); (G.O.); (A.P.)
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Kachmar J, El-Haffaf Z, Bollée G. Atypical ADPKD Due to a DNAJB11 Pathogenic Variant: An Educational Case Report. Can J Kidney Health Dis 2023; 10:20543581231203054. [PMID: 37867501 PMCID: PMC10585986 DOI: 10.1177/20543581231203054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 07/27/2023] [Indexed: 10/24/2023] Open
Abstract
Rationale Due to next-generation sequencing, variants in new genes such as DNAJB11 are recently being identified as causing atypical autosomal dominant polycystic kidney disease (ADPKD). It is important to describe phenotypes associated with these variants in order to increase awareness among clinicians, especially since genetic variability affects ADPKD severity. Presenting Concerns of the Patient We describe a 55-year-old female patient of Haitian origin who presented with slowly deteriorating kidney function, microscopic hematuria, proteinuria, enlarged kidneys with innumerable small cysts, and a family history of chronic kidney disease and cysts. The phenotype was atypical for ADPKD caused by PKD1 or PKD2 variants, since cysts were of small size, kidneys were only moderately enlarged, and the patient had no extra-renal involvement suggestive of typical ADPKD such as liver cysts, pancreatic cysts, cranial aneurysms, or cardiac abnormalities. Diagnoses A panel of genes was analyzed by next-generation massive sequencing techniques, including DNAJB11, DZIP1L, GANAB, HNF1B, PKD1, PKD2, and PKHD1. Genetic testing revealed a heterozygous variant in the DNAJB11 gene (c.123 dup), which is predicted to result in premature protein termination (p. Lys42*) and was classified by the laboratory as likely pathogenic. Interventions She was treated with candesartan 16 mg once daily to address her proteinuria. Outcomes At the time of the most recent follow-up, her proteinuria has increased, and her kidney function continues to slowly deteriorate. Teaching Points DNAJB11 variants are a rare cause of atypical ADPKD. It is important to recognize the clinical features that help distinguish DNAJB11 from PKD1 and PKD2 variants. Atypical ADPKD due to DNAJB11 variants is usually characterized by small cysts, normal kidney size, proteinuria, progressive chronic kidney disease, and phenotypic overlap with autosomal dominant tubulointerstitial kidney disease (ADTKD). It may, however, present itself with enlarged kidneys as was seen in our patient. Genetic testing should be offered whenever a patient presents atypical features of ADPKD, which also requires increased awareness among clinicians regarding the various phenotypes of atypical ADPKD.
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Affiliation(s)
- Jessica Kachmar
- Division of Nephrology, Department of Medicine, Centre Hospitalier de l’Université de Montréal, QC, Canada
| | - Zaki El-Haffaf
- Department of Genetics, Centre Hospitalier de l’Université de Montréal, QC, Canada
| | - Guillaume Bollée
- Division of Nephrology, Department of Medicine, Centre Hospitalier de l’Université de Montréal, QC, Canada
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Boerrigter MM, Duijzer R, te Morsche RHM, Drenth JPH. Heterozygosity of ALG9 in Association with Autosomal Dominant Polycystic Liver Disease. Genes (Basel) 2023; 14:1755. [PMID: 37761895 PMCID: PMC10530326 DOI: 10.3390/genes14091755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 09/29/2023] Open
Abstract
α-1,2-mannosyltransferase (ALG9) germline variants are linked to autosomal dominant polycystic kidney disease (ADPKD). Many individuals affected with ADPKD possess polycystic livers as a common extrarenal manifestation. We performed whole exome sequencing in a female with autosomal dominant polycystic liver disease (ADPLD) without kidney cysts and established the presence of a heterozygous missense variant (c.677G>C p.(Gly226Ala)) in ALG9. In silico pathogenicity prediction and 3D protein modeling determined this variant as pathogenic. Loss of heterozygosity is regularly seen in liver cyst walls. Immunohistochemistry indicated the absence of ALG9 in liver tissue from this patient. ALG9 expression was absent in cyst wall lining from ALG9- and PRKCSH-caused ADPLD patients but present in the liver cyst lining derived from an ADPKD patient with a PKD2 variant. Thus, heterozygous pathogenic variants in ALG9 are also associated with ADPLD. Somatic loss of heterozygosity of the ALG9 enzyme was seen in the ALG9 patient but also in ADPLD patients with a different genetic background. This expanded the phenotypic spectrum of ADPLD to ALG9.
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Affiliation(s)
- Melissa M. Boerrigter
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Renée Duijzer
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- European Reference Network RARE-LIVER, D-20246 Hamburg, Germany
| | - René H. M. te Morsche
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Joost P. H. Drenth
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- European Reference Network RARE-LIVER, D-20246 Hamburg, Germany
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Yang H, Sieben CJ, Schauer RS, Harris PC. Genetic Spectrum of Polycystic Kidney and Liver Diseases and the Resulting Phenotypes. ADVANCES IN KIDNEY DISEASE AND HEALTH 2023; 30:397-406. [PMID: 38097330 PMCID: PMC10746289 DOI: 10.1053/j.akdh.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/21/2023] [Accepted: 04/27/2023] [Indexed: 12/18/2023]
Abstract
Polycystic kidney diseases are a group of monogenically inherited disorders characterized by cyst development in the kidney with defects in primary cilia function central to pathogenesis. Autosomal dominant polycystic kidney disease (ADPKD) has progressive cystogenesis and accounts for 5-10% of kidney failure (KF) patients. There are two major ADPKD genes, PKD1 and PKD2, and seven minor loci. PKD1 accounts for ∼80% of patients and is associated with the most severe disease (KF is typically at 55-65 years); PKD2 accounts for ∼15% of families, with KF typically in the mid-70s. The minor genes are generally associated with milder kidney disease, but for DNAJB11 and ALG5, the age at KF is similar to PKD2. PKD1 and PKD2 have a high level of allelic heterogeneity, with no single pathogenic variant accounting for >2% of patients. Additional genetic complexity includes biallelic disease, sometimes causing very early-onset ADPKD, and mosaicism. Autosomal dominant polycystic liver disease is characterized by severe PLD but limited PKD. The two major genes are PRKCSH and SEC63, while GANAB, ALG8, and PKHD1 can present as ADPKD or autosomal dominant polycystic liver disease. Autosomal recessive polycystic kidney disease typically has an infantile onset, with PKHD1 being the major locus and DZIP1L and CYS1 being minor genes. In addition, there are a range of mainly recessive syndromic ciliopathies with PKD as part of the phenotype. Because of the phenotypic and genic overlap between the diseases, employing a next-generation sequencing panel containing all known PKD and ciliopathy genes is recommended for clinical testing.
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Affiliation(s)
- Hana Yang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester MN
| | - Cynthia J Sieben
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester MN
| | - Rachel S Schauer
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester MN
| | - Peter C Harris
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester MN.
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Ghosh Roy S, Li Z, Guo Z, Long KT, Rehrl S, Tian X, Dong K, Besse W. Dnajb11-Kidney Disease Develops from Reduced Polycystin-1 Dosage but not Unfolded Protein Response in Mice. J Am Soc Nephrol 2023; 34:1521-1534. [PMID: 37332102 PMCID: PMC10482070 DOI: 10.1681/asn.0000000000000164] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 05/18/2023] [Indexed: 06/20/2023] Open
Abstract
SIGNIFICANCE STATEMENT Heterozygous DNAJB11 mutation carriers manifest with small cystic kidneys and renal failure in adulthood. Recessive cases with prenatal cystic kidney dysplasia were recently described. Our in vitro and mouse model studies investigate the proposed disease mechanism as an overlap of autosomal-dominant polycystic kidney disease and autosomal-dominant tubulointerstitial kidney disease pathogenesis. We find that DNAJB11 loss impairs cleavage and maturation of the autosomal-dominant polycystic kidney disease protein polycystin-1 (PC1) and results in dosage-dependent cyst formation in mice. We find that Dnajb11 loss does not activate the unfolded protein response, drawing a fundamental contrast with the pathogenesis of autosomal-dominant tubulointerstitial kidney disease. We instead propose that fibrosis in DNAJB11 -kidney disease may represent an exaggerated response to polycystin-dependent cysts. BACKGROUND Patients with heterozygous inactivating mutations in DNAJB11 manifest with cystic but not enlarged kidneys and renal failure in adulthood. Pathogenesis is proposed to resemble an overlap of autosomal-dominant polycystic kidney disease (ADPKD) and autosomal-dominant tubulointerstitial kidney disease (ADTKD), but this phenotype has never been modeled in vivo . DNAJB11 encodes an Hsp40 cochaperone in the endoplasmic reticulum: the site of maturation of the ADPKD polycystin-1 (PC1) protein and of unfolded protein response (UPR) activation in ADTKD. We hypothesized that investigation of DNAJB11 would shed light on mechanisms for both diseases. METHODS We used germline and conditional alleles to model Dnajb11 -kidney disease in mice. In complementary experiments, we generated two novel Dnajb11-/- cell lines that allow assessment of PC1 C-terminal fragment and its ratio to the immature full-length protein. RESULTS Dnajb11 loss results in a profound defect in PC1 cleavage but with no effect on other cystoproteins assayed. Dnajb11-/- mice are live-born at below the expected Mendelian ratio and die at a weaning age with cystic kidneys. Conditional loss of Dnajb11 in renal tubular epithelium results in PC1 dosage-dependent kidney cysts, thus defining a shared mechanism with ADPKD. Dnajb11 mouse models show no evidence of UPR activation or cyst-independent fibrosis, which is a fundamental distinction from typical ADTKD pathogenesis. CONCLUSIONS DNAJB11 -kidney disease is on the spectrum of ADPKD phenotypes with a PC1-dependent pathomechanism. The absence of UPR across multiple models suggests that alternative mechanisms, which may be cyst-dependent, explain the renal failure in the absence of kidney enlargement.
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Affiliation(s)
- Sounak Ghosh Roy
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut
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9
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Boerrigter MM, te Morsche RHM, Venselaar H, Pastoors N, Geerts AM, Hoorens A, Drenth JPH. Novel α-1,3-Glucosyltransferase Variants and Their Broad Clinical Polycystic Liver Disease Spectrum. Genes (Basel) 2023; 14:1652. [PMID: 37628703 PMCID: PMC10454741 DOI: 10.3390/genes14081652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 08/16/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023] Open
Abstract
Protein-truncating variants in α-1,3-glucosyltransferase (ALG8) are a risk factor for a mild cystic kidney disease phenotype. The association between these variants and liver cysts is limited. We aim to identify pathogenic ALG8 variants in our cohort of autosomal dominant polycystic liver disease (ADPLD) individuals. In order to fine-map the phenotypical spectrum of pathogenic ALG8 variant carriers, we performed targeted ALG8 screening in 478 ADPLD singletons, and exome sequencing in 48 singletons and 4 patients from two large ADPLD families. Eight novel and one previously reported pathogenic variant in ALG8 were discovered in sixteen patients. The ALG8 clinical phenotype ranges from mild to severe polycystic liver disease, and from innumerable small to multiple large hepatic cysts. The presence of <5 renal cysts that do not affect renal function is common in this population. Three-dimensional homology modeling demonstrated that six variants cause a truncated ALG8 protein with abnormal functioning, and one variant is predicted to destabilize ALG8. For the seventh variant, immunostaining of the liver tissue showed a complete loss of ALG8 in the cystic cells. ALG8-associated ADPLD has a broad clinical spectrum, including the possibility of developing a small number of renal cysts. This broadens the ADPLD genotype-phenotype spectrum and narrows the gap between liver-specific ADPLD and kidney-specific ADPKD.
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Affiliation(s)
- Melissa M. Boerrigter
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - René H. M. te Morsche
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Hanka Venselaar
- Center for Molecular and Biomolecular Informatics, Research Institute for Medical Innovation, 6500 HB Nijmegen, The Netherlands
| | - Nikki Pastoors
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Anja M. Geerts
- Department of Gastroenterology and Hepatology, Ghent University Hospital, 9000 Ghent, Belgium
| | - Anne Hoorens
- Department of Pathology, Ghent University Hospital, 9000 Ghent, Belgium
| | - Joost P. H. Drenth
- Department of Gastroenterology and Hepatology, Research Institute for Medical Innovation, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
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10
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Zhao Q, Tan Y, Xiao X, Xiang Q, Yang M, Wang H, Liu S. A novel heterozygous PKD1 variant causing alternative splicing in a Chinese family with autosomal dominant polycystic kidney disease. Mol Genet Genomic Med 2023; 11:e2217. [PMID: 37272738 PMCID: PMC10422069 DOI: 10.1002/mgg3.2217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/04/2023] [Accepted: 05/23/2023] [Indexed: 06/06/2023] Open
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is mainly caused by pathogenic variants of PKD1 and PKD2. Compared to PKD2-related patients, patients with PKD1 pathogenic variants have more severe symptoms, present a gradual decline in renal function, and finally progress to end-stage kidney disease with an earlier mean onset age. METHODS In this study, trio exome sequencing (ES) was performed to reveal the genetic etiology in a Chinese family clinically diagnosed with polycystic kidney, followed by validation through Sanger sequencing on both genomic DNA and cDNA levels. Subsequently, targeted preimplantation genetic testing was provided for the family. RESULTS A novel heterozygous PKD1 variant (c.1717_1722+11del) was detected in the proband and other clinically-affected relatives. Interestingly, cDNA sequencing demonstrated that the variant, despite being annotated as non-frameshift within exon 8, impacted the splicing of PKD1. Two abnormal transcription products were formed: one induced frameshift, while the other caused 133 amino acids to be inserted between exon 8 and exon 9. CONCLUSIONS Our study revealed a novel PKD1 variant using ES as the cause of ADPKD in a Chinese family with multiple affected members. The variant at the exon-intron boundary would induce alternative splicing, which should not be excluded from genetic analysis. Validated on the cDNA level could provide more comprehensive genetic information for disease stratification. And the novel variant expands the spectrum of PKD1 variants in ADPKD. The recurrent risk could be blocked accordingly for the families' offspring.
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Affiliation(s)
- Qianying Zhao
- Department of Medical GeneticsWest China Second University Hospital, Sichuan UniversityChengduChina
- Department of Obstetrics and GynecologyWest China Second University Hospital, Sichuan UniversityChengduChina
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of EducationChengduChina
| | - Yu Tan
- Department of Medical GeneticsWest China Second University Hospital, Sichuan UniversityChengduChina
- Department of Obstetrics and GynecologyWest China Second University Hospital, Sichuan UniversityChengduChina
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of EducationChengduChina
| | - Xiao Xiao
- Department of Medical GeneticsWest China Second University Hospital, Sichuan UniversityChengduChina
- Department of Obstetrics and GynecologyWest China Second University Hospital, Sichuan UniversityChengduChina
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of EducationChengduChina
| | - Qinqin Xiang
- Department of Medical GeneticsWest China Second University Hospital, Sichuan UniversityChengduChina
- Department of Obstetrics and GynecologyWest China Second University Hospital, Sichuan UniversityChengduChina
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of EducationChengduChina
| | - Mei Yang
- Department of Medical GeneticsWest China Second University Hospital, Sichuan UniversityChengduChina
- Department of Obstetrics and GynecologyWest China Second University Hospital, Sichuan UniversityChengduChina
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of EducationChengduChina
| | - He Wang
- Department of Medical GeneticsWest China Second University Hospital, Sichuan UniversityChengduChina
- Department of Obstetrics and GynecologyWest China Second University Hospital, Sichuan UniversityChengduChina
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of EducationChengduChina
| | - Shanling Liu
- Department of Medical GeneticsWest China Second University Hospital, Sichuan UniversityChengduChina
- Department of Obstetrics and GynecologyWest China Second University Hospital, Sichuan UniversityChengduChina
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of EducationChengduChina
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11
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Hort Y, Sullivan P, Wedd L, Fowles L, Stevanovski I, Deveson I, Simons C, Mallett A, Patel C, Furlong T, Cowley MJ, Shine J, Mallawaarachchi A. Atypical splicing variants in PKD1 explain most undiagnosed typical familial ADPKD. NPJ Genom Med 2023; 8:16. [PMID: 37419908 DOI: 10.1038/s41525-023-00362-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 06/26/2023] [Indexed: 07/09/2023] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most common monogenic cause of kidney failure and is primarily associated with PKD1 or PKD2. Approximately 10% of patients remain undiagnosed after standard genetic testing. We aimed to utilise short and long-read genome sequencing and RNA studies to investigate undiagnosed families. Patients with typical ADPKD phenotype and undiagnosed after genetic diagnostics were recruited. Probands underwent short-read genome sequencing, PKD1 and PKD2 coding and non-coding analyses and then genome-wide analysis. Targeted RNA studies investigated variants suspected to impact splicing. Those undiagnosed then underwent Oxford Nanopore Technologies long-read genome sequencing. From over 172 probands, 9 met inclusion criteria and consented. A genetic diagnosis was made in 8 of 9 (89%) families undiagnosed on prior genetic testing. Six had variants impacting splicing, five in non-coding regions of PKD1. Short-read genome sequencing identified novel branchpoint, AG-exclusion zone and missense variants generating cryptic splice sites and a deletion causing critical intron shortening. Long-read sequencing confirmed the diagnosis in one family. Most undiagnosed families with typical ADPKD have splice-impacting variants in PKD1. We describe a pragmatic method for diagnostic laboratories to assess PKD1 and PKD2 non-coding regions and validate suspected splicing variants through targeted RNA studies.
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Affiliation(s)
- Yvonne Hort
- Molecular Genetics of Inherited Kidney Disorders Laboratory, Garvan Institute of Medical Research, Sydney, Australia
| | - Patricia Sullivan
- Children's Cancer Institute, Lowy Cancer Centre, UNSW Sydney, Kensington, NSW, Australia
- School of Clinical Medicine, UNSW Medicine & Health, UNSW Sydney, Kensington, NSW, Australia
| | - Laura Wedd
- Molecular Genetics of Inherited Kidney Disorders Laboratory, Garvan Institute of Medical Research, Sydney, Australia
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW Sydney, Sydney, NSW, Australia
| | - Lindsay Fowles
- Genetic Health Queensland, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
| | - Igor Stevanovski
- Genomic Technologies, Garvan Institute of Medical Research, Sydney, Australia
- Centre for Population Genomics, Garvan Institute of Medical Research and Murdoch Children's Research Institute, Sydney, Australia
| | - Ira Deveson
- Genomic Technologies, Garvan Institute of Medical Research, Sydney, Australia
- Centre for Population Genomics, Garvan Institute of Medical Research and Murdoch Children's Research Institute, Sydney, Australia
| | - Cas Simons
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW Sydney, Sydney, NSW, Australia
- Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - Andrew Mallett
- Department of Renal Medicine, Townsville University Hospital, Townsville, QLD, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
- College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| | - Chirag Patel
- Genetic Health Queensland, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
| | - Timothy Furlong
- Molecular Genetics of Inherited Kidney Disorders Laboratory, Garvan Institute of Medical Research, Sydney, Australia
| | - Mark J Cowley
- Children's Cancer Institute, Lowy Cancer Centre, UNSW Sydney, Kensington, NSW, Australia
- School of Clinical Medicine, UNSW Medicine & Health, UNSW Sydney, Kensington, NSW, Australia
| | - John Shine
- Molecular Genetics of Inherited Kidney Disorders Laboratory, Garvan Institute of Medical Research, Sydney, Australia
| | - Amali Mallawaarachchi
- Molecular Genetics of Inherited Kidney Disorders Laboratory, Garvan Institute of Medical Research, Sydney, Australia.
- Clinical Genetics Service, Institute of Precision Medicine and Bioinformatics, Royal Prince Alfred Hospital, Sydney, Australia.
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12
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Hanna C, Iliuta IA, Besse W, Mekahli D, Chebib FT. Cystic Kidney Diseases in Children and Adults: Differences and Gaps in Clinical Management. Semin Nephrol 2023; 43:151434. [PMID: 37996359 DOI: 10.1016/j.semnephrol.2023.151434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
Cystic kidney diseases, when broadly defined, have a wide differential diagnosis extending from recessive diseases with a prenatal or pediatric diagnosis, to the most common autosomal-dominant polycystic kidney disease primarily affecting adults, and several other genetic or acquired etiologies that can manifest with kidney cysts. The most likely diagnoses to consider when assessing a patient with cystic kidney disease differ depending on family history, age stratum, radiologic characteristics, and extrarenal features. Accurate identification of the underlying condition is crucial to estimate the prognosis and initiate the appropriate management, identification of extrarenal manifestations, and counseling on recurrence risk in future pregnancies. There are significant differences in the clinical approach to investigating and managing kidney cysts in children compared with adults. Next-generation sequencing has revolutionized the diagnosis of inherited disorders of the kidney, despite limitations in access and challenges in interpreting the data. Disease-modifying treatments are lacking in the majority of kidney cystic diseases. For adults with rapid progressive autosomal-dominant polycystic kidney disease, tolvaptan (V2-receptor antagonist) has been approved to slow the rate of decline in kidney function. In this article, we examine the differences in the differential diagnosis and clinical management of cystic kidney disease in children versus adults, and we highlight the progress in molecular diagnostics and therapeutics, as well as some of the gaps meriting further attention.
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Affiliation(s)
- Christian Hanna
- Division of Pediatric Nephrology and Hypertension, Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN; Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN.
| | - Ioan-Andrei Iliuta
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Jacksonville, FL
| | - Whitney Besse
- Section of Nephrology, Department of Internal Medicine, Yale School of Medicine, New Haven, CT
| | - Djalila Mekahli
- PKD Research Group, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium; Department of Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium
| | - Fouad T Chebib
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Jacksonville, FL.
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13
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Lin T, Luo J, Yu H, Dong B, Zhang Q, Zhang W, Chen K, Xiang Y, Liu D, Huang G. Blocker displacement amplification-based genetic diagnosis for autosomal dominant polycystic kidney disease and the clinical outcomes of preimplantation genetic testing. J Assist Reprod Genet 2023; 40:783-792. [PMID: 36773205 PMCID: PMC10224877 DOI: 10.1007/s10815-023-02722-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 01/10/2023] [Indexed: 02/12/2023] Open
Abstract
OBJECTIVE Given that the molecular diagnosis of autosomal dominant polycystic kidney disease (ADPKD) is complicated, we aim to apply blocker displacement amplification (BDA) on the mutational screening of PKD1 and PKD2. METHODS A total of 35 unrelated families with ADPKD were recruited from the Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University (Chongqing, China), from October 2018 to October 2021. Long-range PCR followed by next-generation sequencing were applied for resequencing of PKD1 and PKD2, and the putatively disease-causative variants were verified with BDA. The effects of ADPKD on male and female infertility and the factors influencing the clinical outcomes of preimplantation genetic testing (PGT) for ADPKD were investigated. RESULTS A total of 26 PKD1 variants and 5 PKD2 variants were identified, of which 13 were newly discovered. The BDA system worked effectively for eliminating the interference of pseudogenes in genetic testing of PKD1 (1-33 exons) with different concentrations of genome DNA. The females with ADPKD have no specific infertility factors, while 68.2% of the affected men were with abnormal sperm concentration and/or motility with an indefinite genotype-phenotype relationship. As for PGT, the fertilization rate of couples with the male partner having ADPKD was relatively lower compared to those with the female partner being affected. The ADPKD patients receiving PGT usually achieved high rates of live births. CONCLUSION These findings expanded the variant spectrum of PKD genes and emphasized the application prospect of blocker displacement amplification on PKD1-related genetic diagnosis.
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Affiliation(s)
- Tingting Lin
- Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Health Center for Women and Children, Chongqing, China
- Chongqing Key Laboratory of Human Embryo Engineering, Chongqing, China
| | | | - Haibing Yu
- Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Health Center for Women and Children, Chongqing, China
| | | | - Qi Zhang
- Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Health Center for Women and Children, Chongqing, China
- Chongqing Key Laboratory of Human Embryo Engineering, Chongqing, China
| | - Wei Zhang
- AmCare Genomics Lab, Guangzhou, China
| | - Ke Chen
- Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Health Center for Women and Children, Chongqing, China
| | - Yezhou Xiang
- Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Health Center for Women and Children, Chongqing, China
| | - Dongyun Liu
- Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China.
- Chongqing Health Center for Women and Children, Chongqing, China.
| | - Guoning Huang
- Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China.
- Chongqing Health Center for Women and Children, Chongqing, China.
- Chongqing Key Laboratory of Human Embryo Engineering, Chongqing, China.
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14
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Devlin L, Dhondurao Sudhindar P, Sayer JA. Renal ciliopathies: promising drug targets and prospects for clinical trials. Expert Opin Ther Targets 2023; 27:325-346. [PMID: 37243567 DOI: 10.1080/14728222.2023.2218616] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/12/2023] [Accepted: 05/23/2023] [Indexed: 05/29/2023]
Abstract
INTRODUCTION Renal ciliopathies represent a collection of genetic disorders characterized by deficiencies in the biogenesis, maintenance, or functioning of the ciliary complex. These disorders, which encompass autosomal dominant polycystic kidney disease (ADPKD), autosomal recessive polycystic kidney disease (ARPKD), and nephronophthisis (NPHP), typically result in cystic kidney disease, renal fibrosis, and a gradual deterioration of kidney function, culminating in kidney failure. AREAS COVERED Here we review the advances in basic science and clinical research into renal ciliopathies which have yielded promising small compounds and drug targets, within both preclinical studies and clinical trials. EXPERT OPINION Tolvaptan is currently the sole approved treatment option available for ADPKD patients, while no approved treatment alternatives exist for ARPKD or NPHP patients. Clinical trials are presently underway to evaluate additional medications in ADPKD and ARPKD patients. Based on preclinical models, other potential therapeutic targets for ADPKD, ARPKD, and NPHP look promising. These include molecules targeting fluid transport, cellular metabolism, ciliary signaling and cell-cycle regulation. There is a real and urgent clinical need for translational research to bring novel treatments to clinical use for all forms of renal ciliopathies to reduce kidney disease progression and prevent kidney failure.
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Affiliation(s)
- Laura Devlin
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Praveen Dhondurao Sudhindar
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - John A Sayer
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
- Renal Services, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle Upon Tyne, UK
- NIHR Newcastle Biomedical Research Centre, Newcastle Upon Tyne, UK
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15
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Apple B, Sartori G, Moore B, Chintam K, Singh G, Anand PM, Strande NT, Mirshahi T, Triffo W, Chang AR. Individuals heterozygous for ALG8 protein-truncating variants are at increased risk of a mild cystic kidney disease. Kidney Int 2023; 103:607-615. [PMID: 36574950 PMCID: PMC10012037 DOI: 10.1016/j.kint.2022.11.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 11/10/2022] [Accepted: 11/23/2022] [Indexed: 12/25/2022]
Abstract
ALG8 protein-truncating variants (PTVs) have previously been described in patients with polycystic liver disease and in some cases cystic kidney disease. Given a lack of well-controlled studies, we determined whether individuals heterozygous for ALG8 PTVs are at increased risk of cystic kidney disease in a large, unselected health system-based observational cohort linked to electronic health records in Pennsylvania (Geisinger-Regeneron DiscovEHR MyCode study). Out of 174,172 patients, 236 were identified with ALG8 PTVs. Using ICD-based outcomes, patients with these variants were significantly at increased risk of having any kidney/liver cyst diagnosis (Odds Ratio 2.42, 95% confidence interval: 1.53-3.85), cystic kidney disease (3.03, 1.26-7.31), and nephrolithiasis (1.89, 1.96-2.97). To confirm this finding, blinded radiology review of computed tomography and magnetic resonance imaging studies was completed in a matched cohort of 52 thirty-plus year old ALG8 PTV heterozygotes and related non-heterozygotes. ALG8 PTV heterozygotes were significantly more likely to have cystic kidney disease, defined as four or more kidney cysts (57.7% vs. 7.7%), or bilateral kidney cysts (69.2% vs. 15.4%), but not one or more liver cyst (11.5% vs. 7.7%). In publicly available UK Biobank data, ALG8 PTV heterozygotes were at significantly increased risk of ICD code N28 (other disorders of kidney/ureter) (3.85% vs. 1.33%). ALG8 PTVs were not associated with chronic kidney disease or kidney failure in the MyCode study or the UK Biobank data. Thus, PTVs in ALG8 result in increased risk of a mild cystic kidney disease phenotype.
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Affiliation(s)
- Benjamin Apple
- Department of Medicine, Geisinger Commonwealth School of Medicine, Scranton, Pennsylvania, USA
| | - Gino Sartori
- Department of Radiology, Geisinger, Danville, Pennsylvania, USA
| | - Bryn Moore
- Department of Genomic Health, Geisinger, Danville, Pennsylvania, USA
| | - Kiran Chintam
- Department of Nephrology, Geisinger, Danville, Pennsylvania, USA
| | - Gurmukteshwar Singh
- Department of Nephrology, Geisinger, Danville, Pennsylvania, USA; Center for Kidney Health Research, Department of Population Health Sciences, Geisinger, Danville, Pennsylvania, USA
| | - Prince Mohan Anand
- Department of Nephrology, Medical University of South Carolina, Lancaster, South Carolina, USA
| | - Natasha T Strande
- Department of Genomic Health, Geisinger, Danville, Pennsylvania, USA; Autism and Developmental Medicine Institute, Geisinger, Danville, Pennsylvania, USA
| | - Tooraj Mirshahi
- Department of Genomic Health, Geisinger, Danville, Pennsylvania, USA
| | - William Triffo
- Department of Radiology, Geisinger, Danville, Pennsylvania, USA
| | - Alexander R Chang
- Department of Nephrology, Geisinger, Danville, Pennsylvania, USA; Center for Kidney Health Research, Department of Population Health Sciences, Geisinger, Danville, Pennsylvania, USA.
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16
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Gromadziński L, Paukszto Ł, Lepiarczyk E, Skowrońska A, Lipka A, Makowczenko KG, Łopieńska-Biernat E, Jastrzębski JP, Holak P, Smoliński M, Majewska M. Pulmonary artery embolism: comprehensive transcriptomic analysis in understanding the pathogenic mechanisms of the disease. BMC Genomics 2023; 24:10. [PMID: 36624378 PMCID: PMC9830730 DOI: 10.1186/s12864-023-09110-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 01/02/2023] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Pulmonary embolism (PE) is a severe disease that usually originates from deep vein thrombosis (DVT) of the lower extremities. This study set out to investigate the changes in the transcriptome of the pulmonary artery (PA) in the course of the PE in the porcine model. METHODS The study was performed on 11 male pigs: a thrombus was formed in each right femoral vein in six animals, and then was released to induce PE, the remaining five animals served as a control group. In the experimental animals total RNA was isolated from the PA where the blood clot lodged, and in the control group, from the corresponding PA segments. High-throughput RNA sequencing was used to analyse the global changes in the transcriptome of PA with induced PE (PA-E). RESULTS Applied multistep bioinformatics revealed 473 differentially expressed genes (DEGs): 198 upregulated and 275 downregulated. Functional Gene Ontology annotated 347 DEGs into 27 biological processes, 324 to the 11 cellular components and 346 to the 2 molecular functions categories. In the signaling pathway analysis, KEGG 'protein processing in endoplasmic reticulum' was identified for the mRNAs modulated during PE. The same KEGG pathway was also exposed by 8 differentially alternative splicing genes. Within single nucleotide variants, the 61 allele-specific expression variants were localised in the vicinity of the genes that belong to the cellular components of the 'endoplasmic reticulum'. The discovered allele-specific genes were also classified as signatures of the cardiovascular system. CONCLUSIONS The findings of this research provide the first thorough investigation of the changes in the gene expression profile of PA affected by an embolus. Evidence from this study suggests that the disturbed homeostasis in the biosynthesis of proteins in the endoplasmic reticulum plays a major role in the pathogenesis of PE.
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Affiliation(s)
- Leszek Gromadziński
- grid.412607.60000 0001 2149 6795Department of Cardiology and Internal Medicine, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, Warszawska Str 30, 10-082 Olsztyn, Poland
| | - Łukasz Paukszto
- grid.412607.60000 0001 2149 6795Department of Botany and Nature Protection, University of Warmia and Mazury in Olsztyn, Plac Łódzki 1, 10-727 Olsztyn, Poland
| | - Ewa Lepiarczyk
- grid.412607.60000 0001 2149 6795Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, Warszawska Str 30, 10-082 Olsztyn, Poland
| | - Agnieszka Skowrońska
- grid.412607.60000 0001 2149 6795Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, Warszawska Str 30, 10-082 Olsztyn, Poland
| | - Aleksandra Lipka
- grid.412607.60000 0001 2149 6795Department of Gynecology, and Obstetrics, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, Żołnierska Str 18, 10-561 Olsztyn, Poland
| | - Karol G. Makowczenko
- grid.412607.60000 0001 2149 6795Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland
| | - Elżbieta Łopieńska-Biernat
- grid.412607.60000 0001 2149 6795Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str 1A, 10-719 Olsztyn, Poland
| | - Jan P. Jastrzębski
- grid.412607.60000 0001 2149 6795Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str 1A, 10-719 Olsztyn-Kortowo, Poland
| | - Piotr Holak
- grid.412607.60000 0001 2149 6795Department of Surgery and Radiology With Clinic, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str 14, 10-719 Olsztyn, Poland
| | - Michał Smoliński
- grid.460107.4Clinic of Cardiology and Internal Diseases, University Clinical Hospital in Olsztyn, Warszawska Str 30, 10-082 Olsztyn, Poland
| | - Marta Majewska
- grid.412607.60000 0001 2149 6795Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, Warszawska Str 30, 10-082 Olsztyn, Poland
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17
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Sekine A, Hidaka S, Moriyama T, Shikida Y, Shimazu K, Ishikawa E, Uchiyama K, Kataoka H, Kawano H, Kurashige M, Sato M, Suwabe T, Nakatani S, Otsuka T, Kai H, Katayama K, Makabe S, Manabe S, Shimabukuro W, Nakanishi K, Nishio S, Hattanda F, Hanaoka K, Miura K, Hayashi H, Hoshino J, Tsuchiya K, Mochizuki T, Horie S, Narita I, Muto S. Cystic Kidney Diseases That Require a Differential Diagnosis from Autosomal Dominant Polycystic Kidney Disease (ADPKD). J Clin Med 2022; 11:6528. [PMID: 36362756 PMCID: PMC9657046 DOI: 10.3390/jcm11216528] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/14/2022] [Accepted: 11/01/2022] [Indexed: 09/05/2023] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cystic kidney disease, with patients often having a positive family history that is characterized by a similar phenotype. However, in atypical cases, particularly those in which family history is unclear, a differential diagnosis between ADPKD and other cystic kidney diseases is important. When diagnosing ADPKD, cystic kidney diseases that can easily be excluded using clinical information include: multiple simple renal cysts, acquired cystic kidney disease (ACKD), multilocular renal cyst/multilocular cystic nephroma/polycystic nephroma, multicystic kidney/multicystic dysplastic kidney (MCDK), and unilateral renal cystic disease (URCD). However, there are other cystic kidney diseases that usually require genetic testing, or another means of supplementing clinical information to enable a differential diagnosis of ADPKD. These include autosomal recessive polycystic kidney disease (ARPKD), autosomal dominant tubulointerstitial kidney disease (ADTKD), nephronophthisis (NPH), oral-facial-digital (OFD) syndrome type 1, and neoplastic cystic kidney disease, such as tuberous sclerosis (TSC) and Von Hippel-Lindau (VHL) syndrome. To help physicians evaluate cystic kidney diseases, this article provides a review of cystic kidney diseases for which a differential diagnosis is required for ADPKD.
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Affiliation(s)
- Akinari Sekine
- Nephrology Center, Toranomon Hospital, Tokyo 105-8470, Japan
| | - Sumi Hidaka
- Kidney Disease and Transplant Center, Shonan Kamakura General Hospital, Kanagawa 247-8533, Japan
| | - Tomofumi Moriyama
- Division of Nephrology, Department of Medicine, Kurume University School of Medicine, Fukuoka 830-0011, Japan
| | - Yasuto Shikida
- Department of Nephrology, Saiseikai Nakatsu Hospital, Osaka 530-0012, Japan
| | - Keiji Shimazu
- Department of Nephrology, Saiseikai Nakatsu Hospital, Osaka 530-0012, Japan
| | - Eiji Ishikawa
- Department of Nephrology, Saiseikai Matsusaka General Hospital, Mie 515-8557, Japan
| | - Kiyotaka Uchiyama
- Department of Endocrinology, Metabolism and Nephrology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Hiroshi Kataoka
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo 162-8666, Japan
| | - Haruna Kawano
- Department of Urology, Juntendo University Graduate School of Medicine, Tokyo 113-0033, Japan
- Department of Advanced Informatics for Genetic Disease, Juntendo University Graduate School of Medicine, Tokyo 113-0033, Japan
| | - Mahiro Kurashige
- Division of Kidney and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, Tokyo 105-8461, Japan
| | - Mai Sato
- Division of Nephrology and Rheumatology, National Center for Child Health and Development, Tokyo 157-8535, Japan
| | - Tatsuya Suwabe
- Nephrology Center, Toranomon Hospital, Tokyo 105-8470, Japan
| | - Shinya Nakatani
- Department of Metabolism, Endocrinology and Molecular Medicine, Osaka Metropolitan University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Tadashi Otsuka
- Division of Clinical Nephrology and Rheumatology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - Hirayasu Kai
- Department of Nephrology, Faculty of Medicine, University of Tsukuba, Ibaraki 305-8575, Japan
| | - Kan Katayama
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie 514-8507, Japan
| | - Shiho Makabe
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo 162-8666, Japan
| | - Shun Manabe
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo 162-8666, Japan
| | - Wataru Shimabukuro
- Department of Child Health and Welfare (Pediatrics), Graduate School of Medicine, University of the Ryukyus, Okinawa 903-0215, Japan
| | - Koichi Nakanishi
- Department of Child Health and Welfare (Pediatrics), Graduate School of Medicine, University of the Ryukyus, Okinawa 903-0215, Japan
| | - Saori Nishio
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo 060-8638, Japan
| | - Fumihiko Hattanda
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo 060-8638, Japan
| | - Kazushige Hanaoka
- Department of General Internal Medicine, Daisan Hospital, Jikei University, School of Medicine, Tokyo 105-8471, Japan
| | - Kenichiro Miura
- Department of Pediatric Nephrology, Tokyo Women’s Medical University, Tokyo 162-8666, Japan
| | - Hiroki Hayashi
- Department of Nephrology, Fujita Health University, Aichi 470-1192, Japan
| | - Junichi Hoshino
- Department of Nephrology, Tokyo Women’s Medical University, Tokyo 162-8666, Japan
| | - Ken Tsuchiya
- Department of Blood Purification, Tokyo Women’s Medical University, Tokyo 162-8666, Japan
| | | | - Shigeo Horie
- Department of Urology, Juntendo University Graduate School of Medicine, Tokyo 113-0033, Japan
- Department of Advanced Informatics for Genetic Disease, Juntendo University Graduate School of Medicine, Tokyo 113-0033, Japan
| | - Ichiei Narita
- Division of Clinical Nephrology and Rheumatology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - Satoru Muto
- Department of Urology, Juntendo University Graduate School of Medicine, Tokyo 113-0033, Japan
- Department of Urology, Juntendo University Nerima Hospital, Tokyo 177-8521, Japan
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18
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Which patients with CKD will benefit from genomic sequencing? Synthesizing progress to illuminate the future. Curr Opin Nephrol Hypertens 2022; 31:541-547. [PMID: 36093902 PMCID: PMC9594128 DOI: 10.1097/mnh.0000000000000836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE OF REVIEW This review will summarize and synthesize recent findings in regard to monogenic kidney disorders, including how that evidence is being translated into practice. It will add to existing key knowledge to provide context for clinicians in consolidating existing practice and approaches. RECENT FINDINGS Whilst there are long established factors, which indicate increased likelihood of identifying a monogenic cause for kidney disease, these can now be framed in terms of the identification of new genes, new indications for genomic testing and new evidence for clinical utility of genomic testing in nephrology. Further, inherent in the use of genomics in nephrology are key concepts including robust informed consent, variant interpretation and return of results. Recent findings of variants in genes related to complex or broader kidney phenotypes are emerging in addition to understanding of de novo variants. Phenocopy phenomena are indicating a more pragmatic use of broader gene panels whilst evidence is emerging of a role in unexplained kidney disease. Clinical utility is evolving but is being successfully demonstrated across multiple domains of outcome and practice. SUMMARY We provide an updated framework of evidence to guide application of genomic testing in chronic kidney disease (CKD), building upon existing principles and knowledge to indicate how the practice and implementation of this can be applied today. There are clearly established roles for genomic testing for some patients with CKD, largely those with suspected heritable forms, with these continuing to expand as new evidence emerges.
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19
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Liu P, Zu F, Chen H, Yin X, Tan X. Exosomal DNAJB11 promotes the development of pancreatic cancer by modulating the EGFR/MAPK pathway. Cell Mol Biol Lett 2022; 27:87. [PMID: 36209075 PMCID: PMC9548179 DOI: 10.1186/s11658-022-00390-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 09/19/2022] [Indexed: 12/02/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with invasive and metastatic characteristics and poor prognosis. Intracellular protein homeostasis is associated with invasion and metastasis of pancreatic cancer, but the specific molecular mechanism remains unclear. Our previous studies have revealed that DNAJB11, a key protein in protein homeostasis, is secreted by exosomes in the supernatant of dissociated pancreatic cancer cells with high metastasis. The results from transcriptome sequencing and co-immunoprecipitation (Co-IP)-based liquid chromatography with tandem mass spectrometry (LC–MS/MS) showed that depletion of DNAJB11 levels could increase HSPA5 expression and induce endoplasmic reticulum stress through the PRKR-like endoplasmic reticulum kinase signaling pathway in pancreatic cancer cells. Furthermore, exosomal DNAJB11 promoted cell development of PC cells in vitro and in vivo. In addition, exosomal DNAJB11 could regulate the expression of EGFR and activate the downstream MAPK signaling pathway. Clinical blood samples were collected to evaluate the potential of exosome DNAJB11 as a diagnostic biomarker and therapeutic target for the treatment of pancreatic cancer. This study could provide a new theoretical basis and potential molecular targets for the treatment of pancreatic cancer.
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Affiliation(s)
- Peng Liu
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, 110004, China.,Diagnostic and Therapeutic Center of Pancreatic Diseases of Liaoning Province, Shenyang, 110004, China
| | - Fuqiang Zu
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, 110004, China.,Diagnostic and Therapeutic Center of Pancreatic Diseases of Liaoning Province, Shenyang, 110004, China
| | - Hui Chen
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, 110004, China
| | - Xiaoli Yin
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, 110004, China.
| | - Xiaodong Tan
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, 110004, China. .,Diagnostic and Therapeutic Center of Pancreatic Diseases of Liaoning Province, Shenyang, 110004, China.
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20
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Živná M, Kidd KO, Barešová V, Hůlková H, Kmoch S, Bleyer AJ. Autosomal dominant tubulointerstitial kidney disease: A review. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2022; 190:309-324. [PMID: 36250282 PMCID: PMC9619361 DOI: 10.1002/ajmg.c.32008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 09/10/2022] [Accepted: 09/29/2022] [Indexed: 01/11/2023]
Abstract
The clinical characteristics of autosomal dominant tubulointerstitial kidney disease (ADTKD) include bland urinary sediment, slowly progressive chronic kidney disease (CKD) with many patients reaching end stage renal disease (ESRD) between age 20 and 70 years, and autosomal dominant inheritance. Due to advances in genetic diagnosis, ADTKD is becoming increasingly recognized as a cause of CKD. Pathogenic variants in UMOD, MUC1, and REN are the most common causes of ADTKD. ADTKD-UMOD is also associated with hyperuricemia and gout. ADTKD-REN often presents in childhood with mild hypotension, CKD, hyperkalemia, acidosis, and anemia. ADTKD-MUC1 patients present only with CKD. This review describes the pathophysiology, genetics, clinical manifestation, and diagnosis for ADTKD, with an emphasis on genetic testing and genetic counseling suggestions for patients.
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Affiliation(s)
- Martina Živná
- Research Unit of Rare Diseases, Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of MedicineCharles UniversityPragueCzech Republic
| | - Kendrah O. Kidd
- Research Unit of Rare Diseases, Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of MedicineCharles UniversityPragueCzech Republic,Wake Forest University School of MedicineSection on NephrologyWinston‐SalemNorth CarolinaUSA
| | - Veronika Barešová
- Research Unit of Rare Diseases, Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of MedicineCharles UniversityPragueCzech Republic
| | - Helena Hůlková
- Research Unit of Rare Diseases, Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of MedicineCharles UniversityPragueCzech Republic
| | - Stanislav Kmoch
- Research Unit of Rare Diseases, Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of MedicineCharles UniversityPragueCzech Republic,Wake Forest University School of MedicineSection on NephrologyWinston‐SalemNorth CarolinaUSA
| | - Anthony J. Bleyer
- Research Unit of Rare Diseases, Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of MedicineCharles UniversityPragueCzech Republic,Wake Forest University School of MedicineSection on NephrologyWinston‐SalemNorth CarolinaUSA
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21
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Genetics, pathobiology and therapeutic opportunities of polycystic liver disease. Nat Rev Gastroenterol Hepatol 2022; 19:585-604. [PMID: 35562534 DOI: 10.1038/s41575-022-00617-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/07/2022] [Indexed: 12/12/2022]
Abstract
Polycystic liver diseases (PLDs) are inherited genetic disorders characterized by progressive development of intrahepatic, fluid-filled biliary cysts (more than ten), which constitute the main cause of morbidity and markedly affect the quality of life. Liver cysts arise in patients with autosomal dominant PLD (ADPLD) or in co-occurrence with renal cysts in patients with autosomal dominant or autosomal recessive polycystic kidney disease (ADPKD and ARPKD, respectively). Hepatic cystogenesis is a heterogeneous process, with several risk factors increasing the odds of developing larger cysts. Depending on the causative gene, PLDs can arise exclusively in the liver or in parallel with renal cysts. Current therapeutic strategies, mainly based on surgical procedures and/or chronic administration of somatostatin analogues, show modest benefits, with liver transplantation as the only potentially curative option. Increasing research has shed light on the genetic landscape of PLDs and consequent cholangiocyte abnormalities, which can pave the way for discovering new targets for therapy and the design of novel potential treatments for patients. Herein, we provide a critical and comprehensive overview of the latest advances in the field of PLDs, mainly focusing on genetics, pathobiology, risk factors and next-generation therapeutic strategies, highlighting future directions in basic, translational and clinical research.
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22
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Lemoine H, Raud L, Foulquier F, Sayer JA, Lambert B, Olinger E, Lefèvre S, Knebelmann B, Harris PC, Trouvé P, Desprès A, Duneau G, Matignon M, Poyet A, Jourde-Chiche N, Guerrot D, Lemoine S, Seret G, Barroso-Gil M, Bingham C, Gilbert R, Le Meur Y, Audrézet MP, Cornec-Le Gall E. Monoallelic pathogenic ALG5 variants cause atypical polycystic kidney disease and interstitial fibrosis. Am J Hum Genet 2022; 109:1484-1499. [PMID: 35896117 PMCID: PMC9388391 DOI: 10.1016/j.ajhg.2022.06.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 06/23/2022] [Indexed: 02/06/2023] Open
Abstract
Disorders of the autosomal dominant polycystic kidney disease (ADPKD) spectrum are characterized by the development of kidney cysts and progressive kidney function decline. PKD1 and PKD2, encoding polycystin (PC)1 and 2, are the two major genes associated with ADPKD; other genes include IFT140, GANAB, DNAJB11, and ALG9. Genetic testing remains inconclusive in ∼7% of the families. We performed whole-exome sequencing in a large multiplex genetically unresolved (GUR) family affected by ADPKD-like symptoms and identified a monoallelic frameshift variant (c.703_704delCA) in ALG5. ALG5 encodes an endoplasmic-reticulum-resident enzyme required for addition of glucose molecules to the assembling N-glycan precursors. To identify additional families, we screened a cohort of 1,213 families with ADPKD-like and/or autosomal-dominant tubulointerstitial kidney diseases (ADTKD), GUR (n = 137) or naive to genetic testing (n = 1,076), by targeted massively parallel sequencing, and we accessed Genomics England 100,000 Genomes Project data. Four additional families with pathogenic variants in ALG5 were identified. Clinical presentation was consistent in the 23 affected members, with non-enlarged cystic kidneys and few or no liver cysts; 8 subjects reached end-stage kidney disease from 62 to 91 years of age. We demonstrate that ALG5 haploinsufficiency is sufficient to alter the synthesis of the N-glycan chain in renal epithelial cells. We also show that ALG5 is required for PC1 maturation and membrane and ciliary localization and that heterozygous loss of ALG5 affects PC1 maturation. Overall, our results indicate that monoallelic variants of ALG5 lead to a disorder of the ADPKD-spectrum characterized by multiple small kidney cysts, progressive interstitial fibrosis, and kidney function decline.
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Affiliation(s)
- Hugo Lemoine
- Univ. Brest, Inserm, UMR 1078, GGB, 29200 Brest, France
| | - Loann Raud
- Univ. Brest, Inserm, UMR 1078, GGB, 29200 Brest, France
| | - François Foulquier
- Univ. Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, 59000 Lille, France
| | - John A Sayer
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne NE1 3BZ, UK; The Newcastle upon Tyne Hospitals NHS Foundation Trust, Renal Services, Freeman Road, Newcastle Upon Tyne NE7 7DN, UK; NIHR Newcastle Biomedical Research Centre, Newcastle University, Newcastle Upon Tyne NE4 5PL, UK
| | - Baptiste Lambert
- Univ. Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, 59000 Lille, France
| | - Eric Olinger
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne NE1 3BZ, UK
| | - Siriane Lefèvre
- Univ. Brest, Inserm, UMR 1078, GGB, 29200 Brest, France; Service de Néphrologie, Hôpital de Lorient, 56322 Lorient, France
| | - Bertrand Knebelmann
- Service de Néphrologie et Transplantation rénale, Hôpital Necker, APHP, Université de Paris, Paris, France
| | - Peter C Harris
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55902, USA
| | - Pascal Trouvé
- Univ. Brest, Inserm, UMR 1078, GGB, 29200 Brest, France
| | - Aurore Desprès
- Service de Génétique moléculaire, CHRU Brest, 29609 Brest, France
| | | | - Marie Matignon
- University Paris Est Créteil, Institut National de la Santé et de la Recherche Médicale (INSERM), Assistance Publique des Hôpitaux de Paris (AP-HP), Hôpitaux Universitaires Henri Mondor, Service de Néphrologie et Transplantation, Fédération Hospitalo-Universitaire "Innovative Therapy for Immune Disorders", Créteil, France
| | - Anais Poyet
- Association Régionale d'Aide aux Urémiques du Centre Ouest (ARAUCO), Bourges, France
| | - Noémie Jourde-Chiche
- Centre de Néphrologie et Transplantation Rénale, Hôpital de la Conception (APHM), Marseille, France
| | - Dominique Guerrot
- Service de Néphrologie, Dialyse et Transplantation, CHU de Rouen, Rouen, France
| | - Sandrine Lemoine
- Néphrologie, Dialyse, Hypertension artérielle et Exploration Fonctionnelle rénale, Groupement Hospitalier Edouard Herriot, Hospices Civils de Lyon, Lyon, France
| | | | - Miguel Barroso-Gil
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne NE1 3BZ, UK
| | - Coralie Bingham
- Royal Devon and Exeter NHS Foundation Trust, Exeter EX2 5DW, UK
| | - Rodney Gilbert
- Southampton Children's Hospital, University of Southampton, Southampton SO16 6YD, UK
| | - Yannick Le Meur
- Univ Brest, UMR 1227, LBAI, Labex IGO, 29200 Brest, France; Service de Néphrologie, Hémodialyse et Transplantation rénale, CHRU Brest, 29609 Brest, France
| | - Marie-Pierre Audrézet
- Univ. Brest, Inserm, UMR 1078, GGB, 29200 Brest, France; Service de Génétique moléculaire, CHRU Brest, 29609 Brest, France
| | - Emilie Cornec-Le Gall
- Univ. Brest, Inserm, UMR 1078, GGB, 29200 Brest, France; Service de Néphrologie, Hémodialyse et Transplantation rénale, CHRU Brest, 29609 Brest, France.
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23
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Soraru J, Chakera A, Isbel N, Mallawaarachichi A, Rogers N, Trnka P, Patel C, Mallett A. The evolving role of diagnostic genomics in kidney transplantation. Kidney Int Rep 2022; 7:1758-1771. [PMID: 35967121 PMCID: PMC9366366 DOI: 10.1016/j.ekir.2022.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/11/2022] [Accepted: 05/16/2022] [Indexed: 11/06/2022] Open
Abstract
Monogenic forms of heritable kidney disease account for a significant proportion of chronic kidney disease (CKD) across both pediatric and adult patient populations and up to 11% of patients under 40 years reaching end-stage kidney failure (KF) and awaiting kidney transplant. Diagnostic genomics in the field of nephrology is ever evolving and now plays an important role in assessment and management of kidney transplant recipients and their related donor pairs. Genomic testing can help identify the cause of KF in kidney transplant recipients and assist in prognostication around graft survival and rate of recurrence of primary kidney disease. If a gene variant has been identified in the recipient, at-risk related donors can be assessed for the same and excluded if affected. This paper aims to address the indications for genomic testing in the context for kidney transplantation, the technologies available for testing, the conditions and groups in which testing should be most often considered, and the role for the renal genetics multidisciplinary team in this process.
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24
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Lefèvre S, Audrézet MP, Halimi JM, Longuet H, Bridoux F, Ecotière L, Augusto JF, Duveau A, Renaudineau E, Vigneau C, Frouget T, Charasse C, Gueguen L, Perrichot R, Couvrat G, Seret G. Diagnosis and Risk Factors for Intracranial Aneurysms in Autosomal Polycystic Kidney Disease: A cross-sectional study from the Genkyst Cohort. Nephrol Dial Transplant 2022; 37:2223-2233. [PMID: 35108395 DOI: 10.1093/ndt/gfac027] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is associated with an increased risk for developing intracranial aneurysms (IAs). We aimed to evaluate the frequency of diagnosis of IAs in the cross-sectional, population-based, Genkyst cohort, to describe ADPKD-associated IAs and to analyze the risk factors associated with the occurrence of IAs in ADPKD patients. METHODS Cross-sectional study performed in 26 nephrology centers from the Western part of France. All patients underwent genetic testing for PKD1/PKD2 and other cystogenes. RESULTS Among the 2449 Genkyst participants, 114 (4.65%) had a previous diagnosis of ruptured or unruptured IAs at inclusion, and ∼47% of them had a positive familial history for IAs. Most aneurysms were small and saccular and located in the anterior circulation; 26.3% of the patients had multiple IAs. The cumulative probabilities of a previous diagnosis of IAs were 3.9, 6.2 and 8.1% at 50, 60 and 70 y, respectively. While this risk appeared to be similar in male and female individuals <50 y, after that age, the risk continued to increase more markedly in female patients, reaching 10.8% vs 5.4% at 70 y. The diagnosis rate of IAs was more than twofold higher in PKD1 compared to PKD2 with no influence of PKD1 mutation type or location. In multivariate analysis, female sex, hypertension <35 y, smoking and PKD1 genotype were associated with an increased risk for diagnosis of IAs. CONCLUSIONS This study presents epidemiological data reflecting real-life clinical practice. The increased risk for IAs in postmenopausal women suggests a possible protective role of estrogen.
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Affiliation(s)
- Siriane Lefèvre
- Service de Néphrologie, Hémodialyse et Transplantation rénale, CHRU Brest, Brest 29609, France.,Univ Brest, Inserm, UMR 1078, GGB, Brest, France
| | - Marie-Pierre Audrézet
- Univ Brest, Inserm, UMR 1078, GGB, Brest, France.,Service de génétique moléculaire, CHRU Brest, Brest, France
| | - Jean-Michel Halimi
- Service de Néphrologie-HTA, dialyses, transplantation rénale, Centre Hospitalier Universitaire de Tours, Tours, France.,Université de Tours, Tours, France
| | - Hélène Longuet
- Service de Néphrologie-HTA, dialyses, transplantation rénale, Centre Hospitalier Universitaire de Tours, Tours, France
| | - Frank Bridoux
- Service de Néphrologie, Hémodialyse et Transplantation rénale Centre Hospitalier Universitaire de Poitiers, Poitiers, France
| | - Laure Ecotière
- Service de Néphrologie, Hémodialyse et Transplantation rénale Centre Hospitalier Universitaire de Poitiers, Poitiers, France
| | - Jean-François Augusto
- Service de Néphrologie, Hémodialyse et Transplantation rénale Centre Hospitalier Universitaire de Angers, Angers, France
| | - Agnès Duveau
- Service de Néphrologie, Hémodialyse et Transplantation rénale Centre Hospitalier Universitaire de Angers, Angers, France
| | - Eric Renaudineau
- Service de Néphrologie, Centre hospitalier Broussais, Saint-Malo, France
| | - Cécile Vigneau
- Univ Rennes, CHU Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | | | - Christophe Charasse
- Service de Néphrologie, Centre Hospitalier Yves Le Foll, Saint Brieuc, France
| | - Lorraine Gueguen
- Service de Néphrologie, Centre Hospitalier de Cornouaille, Quimper, France
| | - Régine Perrichot
- Service de Néphrologie, Centre Hospitalier de Bretagne Atlantique, Vannes, France
| | - Grégoire Couvrat
- Service de Néphrologie, Centre Hospitalier Départemental Vendée, La Roche sur Yon, France
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25
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Jordan P, Dorval G, Arrondel C, Morinière V, Tournant C, Audrezet MP, Michel-Calemard L, Putoux A, Lesca G, Labalme A, Whalen S, Loeuillet L, Martinovic J, Attie-Bitach T, Bessières B, Schaefer E, Scheidecker S, Lambert L, Beneteau C, Patat O, Boute-Benejean O, Molin A, Guimiot F, Fontanarosa N, Nizon M, Lefebvre M, Jeanpierre C, Saunier S, Heidet L. Targeted next-generation sequencing in a large series of fetuses with severe renal diseases. Hum Mutat 2022; 43:347-361. [PMID: 35005812 DOI: 10.1002/humu.24324] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/23/2021] [Accepted: 12/14/2021] [Indexed: 11/07/2022]
Abstract
We report the screening of a large panel of genes in a series of 100 fetuses (98 families) affected with severe renal defects. Causative variants were identified in 22% of cases, greatly improving genetic counseling. The percentage of variants explaining the phenotype was different according to the type of phenotype. The highest diagnostic yield was found in cases affected with the ciliopathy-like phenotype (11/15 families and, in addition, a single heterozygous or a homozygous Class 3 variant in PKHD1 in three unrelated cases with autosomal recessive polycystic kidney disease). The lowest diagnostic yield was observed in cases with congenital anomalies of the kidney and urinary tract (9/78 families and, in addition, Class 3 variants in GREB1L in three unrelated cases with bilateral renal agenesis). Inheritance was autosomal recessive in nine genes (PKHD1, NPHP3, CEP290, TMEM67, DNAJB11, FRAS1, ACE, AGT, and AGTR1), and autosomal dominant in six genes (PKD1, PKD2, PAX2, EYA1, BICC1, and MYOCD). Finally, we developed an original approach of next-generation sequencing targeted RNA sequencing using the custom capture panel used for the sequencing of DNA, to validate one MYOCD heterozygous splicing variant identified in two male siblings with megabladder and inherited from their healthy mother.
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Affiliation(s)
- Penelope Jordan
- APHP Service de Génétique, Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Guillaume Dorval
- APHP Service de Génétique, Hôpital Universitaire Necker-Enfants Malades, Paris, France.,Inserm U1163, Laboratoire des Maladies Rénales Héréditaires Institut Imagine, Université de Paris, Paris, France.,APHP Service de Néphrologie Pédiatrique, Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Christelle Arrondel
- Inserm U1163, Laboratoire des Maladies Rénales Héréditaires Institut Imagine, Université de Paris, Paris, France
| | - Vincent Morinière
- APHP Service de Génétique, Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Carole Tournant
- APHP Service de Génétique, Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Marie-Pierre Audrezet
- Service de Génétique moléculaire, Génétique, Génomique et Biotechnologies, UMR 1078, Hôpital Universitaire de Brest, Brest, France
| | - Laurence Michel-Calemard
- Service Biochimie Biologie Moléculaire Grand Est, Hospices Civils de Lyon, Groupement Hospitalier Est, CBPE, Bron, France
| | - Audrey Putoux
- Service de Génétique, Hospices Civils de Lyon, Groupement Hospitalier Est, Bron, France
| | - Gaethan Lesca
- Service de Génétique, Hospices Civils de Lyon, Groupement Hospitalier Est, Bron, France
| | - Audrey Labalme
- Service de Génétique, Hospices Civils de Lyon, Groupement Hospitalier Est, Bron, France
| | - Sandra Whalen
- APHP UF de Génétique Clinique, Centre de Référence des Anomalies du Développement et Syndromes Malformatifs, APHP, Hôpital Armand Trousseau, ERN ITHACA, Sorbonne Université, Paris, France
| | - Laurence Loeuillet
- APHP Service d'Embryofœtopathologie, Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Jelena Martinovic
- APHP Service de Fœtopathologie, Hôpital Universitaire Antoine Béclère, Clamart, France
| | - Tania Attie-Bitach
- APHP Service d'Embryofœtopathologie, Hôpital Universitaire Necker-Enfants Malades, Paris, France.,Inserm U 1163, Institut Imagine, Université de Paris, Paris, France
| | - Bettina Bessières
- APHP Service d'Embryofœtopathologie, Hôpital Universitaire Necker-Enfants Malades, Paris, France.,Inserm U 1163, Institut Imagine, Université de Paris, Paris, France
| | - Elise Schaefer
- Service de Génétique Médicale, Institut de Génétique médicale d'Alsace, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Sophie Scheidecker
- Service de Génétique Médicale, Institut de Génétique médicale d'Alsace, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Laetitia Lambert
- Service de Génétique Médicale, Centre Hospitalier Régional Universitaire de Nancy, Nancy, France
| | - Claire Beneteau
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Olivier Patat
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Toulouse, Toulouse, France
| | - Odile Boute-Benejean
- Service de Génétique Médicale, Hôpital Jeanne de Flandre, Centre Hospitalier Universitaire de Lille, Lille, France
| | - Arnaud Molin
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Caen, Caen, France
| | - Fabien Guimiot
- APHP Service d'Embryo-Fœtopathologie, Hôpital Universitaire Robert Debré, Paris, France
| | | | - Mathilde Nizon
- Service de Génétique Médicale, CHU Nantes, L'institut Du Thorax, INSERM, CNRS, UNIV Nantes, Nantes, France
| | - Mathilde Lefebvre
- APHP Service de Pathologie fœtale, Hôpital Universitaire Armand Trousseau, Paris, France
| | - Cécile Jeanpierre
- Inserm U1163, Laboratoire des Maladies Rénales Héréditaires Institut Imagine, Université de Paris, Paris, France
| | - Sophie Saunier
- Inserm U1163, Laboratoire des Maladies Rénales Héréditaires Institut Imagine, Université de Paris, Paris, France
| | - Laurence Heidet
- Inserm U1163, Laboratoire des Maladies Rénales Héréditaires Institut Imagine, Université de Paris, Paris, France.,APHP Service de Néphrologie Pédiatrique, Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Hôpital Universitaire Necker-Enfants Malades, Paris, France
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26
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Senum SR, Li Y(SM, Benson KA, Joli G, Olinger E, Lavu S, Madsen CD, Gregory AV, Neatu R, Kline TL, Audrézet MP, Outeda P, Nau CB, Meijer E, Ali H, Steinman TI, Mrug M, Phelan PJ, Watnick TJ, Peters DJ, Ong AC, Conlon PJ, Perrone RD, Cornec-Le Gall E, Hogan MC, Torres VE, Sayer JA, Harris PC, Harris PC. Monoallelic IFT140 pathogenic variants are an important cause of the autosomal dominant polycystic kidney-spectrum phenotype. Am J Hum Genet 2022; 109:136-156. [PMID: 34890546 DOI: 10.1016/j.ajhg.2021.11.016] [Citation(s) in RCA: 65] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 11/15/2021] [Indexed: 12/18/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD), characterized by progressive cyst formation/expansion, results in enlarged kidneys and often end stage kidney disease. ADPKD is genetically heterogeneous; PKD1 and PKD2 are the common loci (∼78% and ∼15% of families) and GANAB, DNAJB11, and ALG9 are minor genes. PKD is a ciliary-associated disease, a ciliopathy, and many syndromic ciliopathies have a PKD phenotype. In a multi-cohort/-site collaboration, we screened ADPKD-diagnosed families that were naive to genetic testing (n = 834) or for whom no PKD1 and PKD2 pathogenic variants had been identified (n = 381) with a PKD targeted next-generation sequencing panel (tNGS; n = 1,186) or whole-exome sequencing (WES; n = 29). We identified monoallelic IFT140 loss-of-function (LoF) variants in 12 multiplex families and 26 singletons (1.9% of naive families). IFT140 is a core component of the intraflagellar transport-complex A, responsible for retrograde ciliary trafficking and ciliary entry of membrane proteins; bi-allelic IFT140 variants cause the syndromic ciliopathy, short-rib thoracic dysplasia (SRTD9). The distinctive monoallelic phenotype is mild PKD with large cysts, limited kidney insufficiency, and few liver cysts. Analyses of the cystic kidney disease probands of Genomics England 100K showed that 2.1% had IFT140 LoF variants. Analysis of the UK Biobank cystic kidney disease group showed probands with IFT140 LoF variants as the third most common group, after PKD1 and PKD2. The proximity of IFT140 to PKD1 (∼0.5 Mb) in 16p13.3 can cause diagnostic confusion, and PKD1 variants could modify the IFT140 phenotype. Importantly, our studies link a ciliary structural protein to the ADPKD spectrum.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Peter C Harris
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA.
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27
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Pisani I, Allinovi M, Palazzo V, Zanelli P, Gentile M, Farina MT, Giuliotti S, Cravedi P, Delsante M, Maggiore U, Fiaccadori E, Manenti L. OUP accepted manuscript. Clin Kidney J 2022; 15:1179-1187. [PMID: 35664268 PMCID: PMC9155219 DOI: 10.1093/ckj/sfac032] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Indexed: 11/15/2022] Open
Abstract
Background Methods Results Conclusions
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Affiliation(s)
- Isabella Pisani
- Unità Operativa Nefrologia, Azienda-Ospedaliero Universitaria di Parma & Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
| | - Marco Allinovi
- Nephrology, Dialysis and Transplantation Unit, Careggi University Hospital, Florence, Italy
| | - Viviana Palazzo
- Medical Genetics Unit, Meyer Children's University Hospital, Florence, Italy
| | - Paola Zanelli
- Unità di Immunogenetica dei Trapianti, Azienda-Ospedaliero Universitaria di Parma, Parma, Italy
| | - Micaela Gentile
- Unità Operativa Nefrologia, Azienda-Ospedaliero Universitaria di Parma & Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
| | - Maria Teresa Farina
- Unità Operativa Nefrologia, Azienda-Ospedaliero Universitaria di Parma & Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
| | - Sara Giuliotti
- Unità Operativa Radiologia, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy
| | - Paolo Cravedi
- Department of Medicine, Renal Division, Icahn School of Medicine at Mount Sinai, NY, USA
| | - Marco Delsante
- Unità Operativa Nefrologia, Azienda-Ospedaliero Universitaria di Parma & Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
| | - Umberto Maggiore
- Unità Operativa Nefrologia, Azienda-Ospedaliero Universitaria di Parma & Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
| | - Enrico Fiaccadori
- Unità Operativa Nefrologia, Azienda-Ospedaliero Universitaria di Parma & Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy
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28
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Mabillard H, Olinger E, Sayer JA. UMOD and you! Explaining a rare disease diagnosis. JOURNAL OF RARE DISEASES (BERLIN, GERMANY) 2022; 1:4. [PMID: 36569465 PMCID: PMC9767401 DOI: 10.1007/s44162-022-00005-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 07/24/2022] [Indexed: 12/12/2022]
Abstract
The precise molecular genetic diagnosis of a rare inherited disease is nearly always a prolonged odyssey. Fortunately, modern molecular testing strategies are allowing more diagnoses to be made. There are many different rare inherited kidney diseases and both the genetic heterogeneity of these conditions and the clinical diversity often leads to confusing nomenclature. Autosomal dominant tubulointerstitial kidney disease (ADTKD) is an example of this. ADTKD, an inherited kidney disease that leads to worsening of kidney function over time, often culminating in end stage kidney disease, accounting for around 2% of this cohort. UMOD is the most common gene implicated in this disorder but there are at least 6 subtypes. At present, there are no specific treatments for ADTKD. Here, we review the current understanding of this condition and provide patient-centred information to allow conceptual understanding of this disease to allow better recognition, diagnosis and management.
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Affiliation(s)
- Holly Mabillard
- grid.1006.70000 0001 0462 7212Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ UK ,grid.420004.20000 0004 0444 2244Renal Services, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN UK
| | - Eric Olinger
- grid.1006.70000 0001 0462 7212Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ UK
| | - John A. Sayer
- grid.1006.70000 0001 0462 7212Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ UK ,grid.420004.20000 0004 0444 2244Renal Services, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN UK ,grid.454379.8NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne, NE4 5PL UK
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29
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Mabillard H, Sayer JA, Olinger E. Clinical and genetic spectra of autosomal dominant tubulointerstitial kidney disease. Nephrol Dial Transplant 2021; 38:271-282. [PMID: 34519781 PMCID: PMC9923703 DOI: 10.1093/ndt/gfab268] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Indexed: 12/23/2022] Open
Abstract
Autosomal dominant tubulointerstitial kidney disease (ADTKD) is a clinical entity defined by interstitial fibrosis with tubular damage, bland urinalysis and progressive kidney disease. Mutations in UMOD and MUC1 are the most common causes of ADTKD but other rarer (REN, SEC61A1), atypical (DNAJB11) or heterogeneous (HNF1B) subtypes have been described. Raised awareness, as well as the implementation of next-generation sequencing approaches, have led to a sharp increase in reported cases. ADTKD is now believed to be one of the most common monogenic forms of kidney disease and overall it probably accounts for ∼5% of all monogenic causes of chronic kidney disease. Through international efforts and systematic analyses of patient cohorts, critical insights into clinical and genetic spectra of ADTKD, genotype-phenotype correlations as well as innovative diagnostic approaches have been amassed during recent years. In addition, intense research efforts are addressed towards deciphering and rescuing the cellular pathways activated in ADTKD. A better understanding of these diseases and of possible commonalities with more common causes of kidney disease may be relevant to understand and target mechanisms leading to fibrotic kidney disease in general. Here we highlight recent advances in our understanding of the different subtypes of ADTKD with an emphasis on the molecular underpinnings and its clinical presentations.
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Affiliation(s)
- Holly Mabillard
- Faculty of Medical Sciences, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK,Renal Services, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - John A Sayer
- Faculty of Medical Sciences, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK,Renal Services, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK,NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne, UK
| | - Eric Olinger
- Faculty of Medical Sciences, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK,Correspondence to: Eric Olinger; E-mail:
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30
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Molecular genetics of renal ciliopathies. Biochem Soc Trans 2021; 49:1205-1220. [PMID: 33960378 DOI: 10.1042/bst20200791] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 04/12/2021] [Accepted: 04/14/2021] [Indexed: 12/25/2022]
Abstract
Renal ciliopathies are a heterogenous group of inherited disorders leading to an array of phenotypes that include cystic kidney disease and renal interstitial fibrosis leading to progressive chronic kidney disease and end-stage kidney disease. The renal tubules are lined with epithelial cells that possess primary cilia that project into the lumen and act as sensory and signalling organelles. Mutations in genes encoding ciliary proteins involved in the structure and function of primary cilia cause ciliopathy syndromes and affect many organ systems including the kidney. Recognised disease phenotypes associated with primary ciliopathies that have a strong renal component include autosomal dominant and recessive polycystic kidney disease and their various mimics, including atypical polycystic kidney disease and nephronophthisis. The molecular investigation of inherited renal ciliopathies often allows a precise diagnosis to be reached where renal histology and other investigations have been unhelpful and can help in determining kidney prognosis. With increasing molecular insights, it is now apparent that renal ciliopathies form a continuum of clinical phenotypes with disease entities that have been classically described as dominant or recessive at both extremes of the spectrum. Gene-dosage effects, hypomorphic alleles, modifier genes and digenic inheritance further contribute to the genetic complexity of these disorders. This review will focus on recent molecular genetic advances in the renal ciliopathy field with a focus on cystic kidney disease phenotypes and the genotypes that lead to them. We discuss recent novel insights into underlying disease mechanisms of renal ciliopathies that might be amenable to therapeutic intervention.
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31
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Ateş EA, Turkyilmaz A, Delil K, Alavanda C, Söylemez MA, Geçkinli BB, Ata P, Arman A. Biallelic Mutations in DNAJB11 are Associated with Prenatal Polycystic Kidney Disease in a Turkish Family. Mol Syndromol 2021; 12:179-185. [PMID: 34177435 DOI: 10.1159/000513611] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 12/05/2020] [Indexed: 11/19/2022] Open
Abstract
Polycystic kidney disease (PKD) is a life-threatening condition resulting in end-stage renal disease. Two major forms of PKD are defined according to the inheritance pattern. Autosomal dominant PKD (ADPKD) is characterized by renal cysts, where nearly half of the patients suffers from renal failure in the 7th decade of life. Autosomal recessive PKD (ARPKD) is a rarer and more severe form presenting in childhood. Whole-exome sequencing (WES) analyses was performed to investigate molecular causes of the disease in the fetus. In this study, we present 2 fetuses prenatally diagnosed with PKD in a consanguineous family. WES analysis of the second fetus revealed a homozygous variant (c.740+1G>A) in DNAJB11 which is related to ADPKD. This study reveals that DNAJB11 biallelic mutations may cause an antenatal severe form of ARPKD and contributes to understanding the DNAJB11-related ADPKD phenotype. The possibility of ARPKD due to biallelic mutations in ADPKD genes should be considered in genetic counseling.
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Affiliation(s)
- Esra Arslan Ateş
- Department of Medical Genetics, Marmara University Pendik Training and Research Hospital, İstanbul, Turkey
| | - Ayberk Turkyilmaz
- Department of Medical Genetics, Karadeniz Technical University School of Medicine, Trabzon, Turkey
| | - Kenan Delil
- Department of Medical Genetics, Marmara University School of Medicine, İstanbul, Turkey
| | - Ceren Alavanda
- Department of Medical Genetics, Marmara University School of Medicine, İstanbul, Turkey
| | - Mehmet Ali Söylemez
- Department of Medical Genetics, Marmara University School of Medicine, İstanbul, Turkey
| | - Bilgen Bilge Geçkinli
- Department of Medical Genetics, Marmara University School of Medicine, İstanbul, Turkey
| | - Pinar Ata
- Department of Medical Genetics, Marmara University School of Medicine, İstanbul, Turkey
| | - Ahmet Arman
- Department of Medical Genetics, Marmara University School of Medicine, İstanbul, Turkey
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32
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Boerrigter MM, Bongers EMHF, Lugtenberg D, Nevens F, Drenth JPH. Polycystic liver disease genes: Practical considerations for genetic testing. Eur J Med Genet 2021; 64:104160. [PMID: 33556586 DOI: 10.1016/j.ejmg.2021.104160] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/26/2021] [Accepted: 01/31/2021] [Indexed: 12/15/2022]
Abstract
The development of a polycystic liver is a characteristic of the monogenic disorders: autosomal dominant polycystic kidney disease (ADPKD), autosomal recessive polycystic kidney disease (ARPKD), and autosomal dominant polycystic liver disease (ADPLD). Respectively two and one genes mainly cause ADPKD and ARPKD. In contrast, ADPLD is caused by at least six different genes which combined do not even explain the disease development in over half of the ADPLD population. Genetic testing is mainly performed to confirm the likelihood of developing PKD and if renal therapy is essential. However, pure ADPLD patients are frequently not genetically screened as knowledge about the genotype-phenotype correlation is currently limited. This paper will clarify the essence of genetic testing in ADPLD patients.
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Affiliation(s)
- Melissa M Boerrigter
- Department of Gastroenterology and Hepatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Ernie M H F Bongers
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Dorien Lugtenberg
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Frederik Nevens
- Department of Gastroenterology and Hepatology, University Hospitals KU Leuven, Leuven, Belgium
| | - Joost P H Drenth
- Department of Gastroenterology and Hepatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.
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33
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Schaeffer C, Olinger E. Clinical and genetic spectra of kidney disease caused by REN mutations. Kidney Int 2020; 98:1397-1400. [PMID: 33276865 DOI: 10.1016/j.kint.2020.08.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/05/2020] [Accepted: 08/10/2020] [Indexed: 12/16/2022]
Abstract
Heterozygous mutations in REN cause autosomal dominant tubulointerstitial kidney disease (ADTKD), an increasingly recognized entity characterized by interstitial fibrosis and tubular damage. In contrast to more common forms of ADTKD, the rarity of ADTKD-REN has precluded a thorough disease characterization. Živná and colleagues take advantage of an international patient cohort to expand the genetic and clinical spectra of ADTKD-REN and to establish genotype-phenotype correlations with important implications for patient care.
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Affiliation(s)
- Céline Schaeffer
- Molecular Genetics of Renal Disorders, Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Eric Olinger
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.
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34
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Suwabe T, Chamberlain AM, Killian JM, King BF, Gregory AV, Madsen CD, Wang X, Kline TL, Chebib FT, Hogan MC, Kamath PS, Harris PC, Torres VE. Epidemiology of autosomal-dominant polycystic liver disease in Olmsted county. JHEP Rep 2020; 2:100166. [PMID: 33145487 PMCID: PMC7593615 DOI: 10.1016/j.jhepr.2020.100166] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/15/2020] [Accepted: 07/22/2020] [Indexed: 12/25/2022] Open
Abstract
Background & Aims Isolated autosomal-dominant polycystic liver disease (ADPLD) is generally considered a rare disease. However, the frequency of truncating mutations to ADPLD genes in large, population sequencing databases is 1:496. With the increasing use of abdominal imaging, incidental detection of hepatic cysts and ADPLD has become more frequent. The present study was performed to ascertain the incidence and point prevalence of ADPLD in Olmsted County, MN, USA, and how these are impacted by the increasing utilisation of abdominal imaging. Methods The Rochester Epidemiology Project and radiology databases of Mayo Clinic and Olmsted Medical Center were searched to identify all subjects meeting diagnostic criteria for definite, likely, or possible ADPLD. Annual incidence rates were calculated using incident cases during 1980–2016 as numerator, and age- and sex-specific estimates of the population of Olmsted County as denominator. Point prevalence was calculated using prevalence cases as numerator, and age- and sex-specific estimates of the population of Olmsted County on 1 January 2010 as denominator. Results The incidence rate and point prevalence of combined definite and likely ADPLD were 1.01 per 100,000 person-years and 9.5 per 100,000 population, respectively. Only 15 of 35 definite and likely incident ADPLD cases had received a diagnostic code, and only 8 had clinically significant hepatomegaly. The incidence rates were much higher when adding possible cases, mainly identified through radiology databases, particularly in recent years and in older patients because of the increased utilisation of imaging studies. Conclusions Clinically significant isolated ADPLD is a rare disease with a prevalence <1:10,000 population. The overall prevalence of ADPLD, however, to a large extent not clinically significant, is likely much higher and closer to the reported genetic prevalence. Lay summary Isolated autosomal-dominant polycystic liver disease (ADPLD) is generally considered a rare disease. However, we demonstrate that it is a relatively common disease, which is rarely (<1:10,000 population) clinically significant. Isolated autosomal-dominant polycystic liver disease (ADPLD) is generally considered a rare disease. Truncating mutations to ADPLD genes are fairly common (1:496) in large, population sequencing databases. We identified 35 individuals meeting diagnostic criteria for definite or likely ADPLD and 99 additional patients with possible ADPLD. The point prevalence of definite or likely ADPLD on 01/01/2010 was 9.5/100,000 or 36.0/100,000 population if adding possible cases. Clinically significant isolated ADPLD is rare (<1:10,000 population), but the overall prevalence is likely much higher.
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Affiliation(s)
- Tatsuya Suwabe
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | | | - Jill M Killian
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - Bernard F King
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Adriana V Gregory
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Charles D Madsen
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Xiaofang Wang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | | | - Fouad T Chebib
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Marie C Hogan
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Patrick S Kamath
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
| | - Peter C Harris
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
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35
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Jordan P, Arrondel C, Bessières B, Tessier A, Attié-Bitach T, Guterman S, Morinière V, Antignac C, Saunier S, Gubler MC, Heidet L. Bi-allelic pathogenic variations in DNAJB11 cause Ivemark II syndrome, a renal-hepatic-pancreatic dysplasia. Kidney Int 2020; 99:405-409. [PMID: 33129895 DOI: 10.1016/j.kint.2020.09.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/10/2020] [Accepted: 09/17/2020] [Indexed: 12/16/2022]
Abstract
DNAJB11 (DnaJ Heat Shock Protein Family (Hsp40) Member B11) heterozygous loss of function variations have been reported in autosomal dominant cystic kidney disease with extensive fibrosis, associated with maturation and trafficking defect involving both the autosomal dominant polycystic kidney disease protein polycystin-1 and the autosomal dominant tubulointerstitial kidney disease protein uromodulin. Here we show that biallelic pathogenic variations in DNAJB11 lead to a severe fetal disease including enlarged cystic kidneys, dilation and proliferation of pancreatic duct cells, and liver ductal plate malformation, an association known as Ivemark II syndrome. Cysts of the kidney were developed exclusively from uromodulin negative tubular segments. In addition, tubular cells from the affected kidneys had elongated primary cilia, a finding previously reported in ciliopathies. Thus, our data show that the recessive disease associated with DNAJB11 variations is a ciliopathy rather than a disease of the autosomal dominant tubulointerstitial kidney disease spectrum, and prompt screening of DNAJB11 in fetal hyperechogenic/cystic kidneys.
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Affiliation(s)
- Penelope Jordan
- APHP, Génétique moléculaire, Hôpital universitaire Necker-Enfants malades, Paris, France
| | - Christelle Arrondel
- Laboratoire des Maladies rénales héréditaires, Institut Imagine, Inserm U1163, Université de Paris, Paris, France
| | - Bettina Bessières
- APHP, Embryofœtopathologie, Service d'Histologie-Embryologie-Cytogénétique, Hôpital universitaire Necker-Enfants malades, Paris, France
| | - Aude Tessier
- APHP, Embryofœtopathologie, Service d'Histologie-Embryologie-Cytogénétique, Hôpital universitaire Necker-Enfants malades, Paris, France
| | - Tania Attié-Bitach
- APHP, Embryofœtopathologie, Service d'Histologie-Embryologie-Cytogénétique, Hôpital universitaire Necker-Enfants malades, Paris, France; Université de Paris, Imagine Institute, Paris, France
| | - Sarah Guterman
- APHP, Obstétrique et Médecine fœtale, Hôpital universitaire Necker-Enfants malades, Paris, France
| | - Vincent Morinière
- APHP, Génétique moléculaire, Hôpital universitaire Necker-Enfants malades, Paris, France
| | - Corinne Antignac
- APHP, Génétique moléculaire, Hôpital universitaire Necker-Enfants malades, Paris, France; Laboratoire des Maladies rénales héréditaires, Institut Imagine, Inserm U1163, Université de Paris, Paris, France; Université de Paris, Imagine Institute, Paris, France
| | - Sophie Saunier
- Laboratoire des Maladies rénales héréditaires, Institut Imagine, Inserm U1163, Université de Paris, Paris, France
| | - Marie-Claire Gubler
- Laboratoire des Maladies rénales héréditaires, Institut Imagine, Inserm U1163, Université de Paris, Paris, France
| | - Laurence Heidet
- Laboratoire des Maladies rénales héréditaires, Institut Imagine, Inserm U1163, Université de Paris, Paris, France; APHP, Néphrologie pédiatrique, Centre de Référence MARHEA, Hôpital universitaire Necker-Enfants malades, Paris, France.
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36
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Hu J, Harris PC. Regulation of polycystin expression, maturation and trafficking. Cell Signal 2020; 72:109630. [PMID: 32275942 PMCID: PMC7269868 DOI: 10.1016/j.cellsig.2020.109630] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/03/2020] [Accepted: 04/04/2020] [Indexed: 12/26/2022]
Abstract
The major autosomal dominant polycystic kidney disease (ADPKD) genes, PKD1 and PKD2, are wildly expressed at the organ and tissue level. PKD1 encodes polycystin 1 (PC1), a large membrane associated receptor-like protein that can complex with the PKD2 product, PC2. Various cellular locations have been described for both PC1, including the plasma membrane and extracellular vesicles, and PC2, especially the endoplasmic reticulum (ER), but compelling evidence indicates that the primary cilium, a sensory organelle, is the key site for the polycystin complex to prevent PKD. As with other membrane proteins, the ER biogenesis pathway is key to appropriately folding, performing quality control, and exporting fully folded PC1 to the Golgi apparatus. There is a requirement for binding with PC2 and cleavage of PC1 at the GPS for this folding and export to occur. Six different monogenic defects in this pathway lead to cystic disease development, with PC1 apparently particularly sensitive to defects in this general protein processing pathway. Trafficking of membrane proteins, and the polycystins in particular, through the Golgi to the primary cilium have been analyzed in detail, but at this time, there is no clear consensus on a ciliary targeting sequence required to export proteins to the cilium. After transitioning though the trans-Golgi network, polycystin-bearing vesicles are likely sorted to early or recycling endosomes and then transported to the ciliary base, possibly via docking to transition fibers (TF). The membrane-bound polycystin complex then undergoes facilitated trafficking through the transition zone, the diffusion barrier at the base of the cilium, before entering the cilium. Intraflagellar transport (IFT) may be involved in moving the polycystins along the cilia, but data also indicates other mechanisms. The ciliary polycystin complex can be ubiquitinated and removed from cilia by internalization at the ciliary base and may be sent back to the plasma membrane for recycling or to lysosomes for degradation. Monogenic defects in processes regulating the protein composition of cilia are associated with syndromic disorders involving many organ systems, reflecting the pleotropic role of cilia during development and for tissue maintenance. Many of these ciliopathies have renal involvement, likely because of faulty polycystin signaling from cilia. Understanding the expression, maturation and trafficking of the polycystins helps understand PKD pathogenesis and suggests opportunities for therapeutic intervention.
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Affiliation(s)
- Jinghua Hu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA; Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA.
| | - Peter C Harris
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA; Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA.
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