1
|
Pinon M, Kamath BM. What's new in pediatric genetic cholestatic liver disease: advances in etiology, diagnostics and therapeutic approaches. Curr Opin Pediatr 2024:00008480-990000000-00198. [PMID: 38957097 DOI: 10.1097/mop.0000000000001380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
PURPOSE OF REVIEW To highlight recent advances in pediatric cholestatic liver disease, including promising novel prognostic markers and new therapies. FINDINGS Identification of additional genetic variants associated with progressive familial intrahepatic cholestasis (PFIC) phenotype and new genetic cholangiopathies, with an emerging role of ciliopathy genes. Genotype severity predicts outcomes in bile salt export pump (BSEP) deficiency, and post-biliary diversion serum bile acid levels significantly affect native liver survival in BSEP and progressive familial intrahepatic cholestasis type 1 (FIC1 deficiency) patients. Heterozygous variants in the MDR3 gene have been associated with various cholestatic liver disease phenotypes in adults. Ileal bile acid transporter (IBAT) inhibitors, approved for pruritus in PFIC and Alagille Syndrome (ALGS), have been associated with improved long-term quality of life and event-free survival. SUMMARY Next-generation sequencing (NGS) technologies have revolutionized diagnostic approaches, while discovery of new intracellular signaling pathways show promise in identifying therapeutic targets and personalized strategies. Bile acids may play a significant role in hepatic damage progression, suggesting their monitoring could guide cholestatic liver disease management. IBAT inhibitors should be incorporated early into routine management algorithms for pruritus. Data are emerging as to whether IBAT inhibitors are impacting disease biology and modifying the natural history of the cholestasis.
Collapse
Affiliation(s)
- Michele Pinon
- Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | | |
Collapse
|
2
|
Papingi D, Bierhals T, Volk AE, Kutsche M, Paul K, Herget T. A novel TTC26 variant in a patient with hexadactyly, pituitary stalk interruption, hepatopathy, nephropathy, and bilateral lip-palate cleft: A case report and expansion of the phenotype. Am J Med Genet A 2024; 194:e63515. [PMID: 38135897 DOI: 10.1002/ajmg.a.63515] [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: 09/07/2023] [Revised: 10/29/2023] [Accepted: 12/09/2023] [Indexed: 12/24/2023]
Abstract
Biallelic pathogenic variants in the TTC26 gene are known to cause BRENS (biliary, renal, neurological, skeletal) syndrome, an ultra-rare autosomal recessive condition with only few patients published to date. BRENS syndrome is characterized by hexadactyly, severe neonatal cholestasis, and involvement of the brain, heart, and kidney, however the full phenotypic and genotypic spectrum is unknown. Here, we report on a previously undescribed homozygous intronic TTC26 variant (c.1006-5 T > C) in a patient showing some of the known TTC26-associated features like hexadactyly, hypopituitarism, hepatopathy, nephropathy, and congenital heart defect. Moreover, he presented with a suspected unilateral hearing loss and bilateral cleft lip-palate. The variant is considered to affect correct splicing by the loss of the canonical acceptor splice site and activation of a cryptic acceptor splice site. Hereby, our patient represents one additional patient with BRENS syndrome carrying a previously unreported TTC26 variant. Furthermore, we confirm the involvement of the pituitary gland to be a common clinical feature of the syndrome and broaden the clinical spectrum of TTC26 ciliopathy to include facial clefts and a probable hearing involvement.
Collapse
Affiliation(s)
- Dzhoy Papingi
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tatjana Bierhals
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alexander E Volk
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kevin Paul
- University Children's Hospital, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Theresia Herget
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
3
|
Zheng Y, Guo H, Chen L, Cheng W, Yan K, Zhang Z, Li M, Jin Y, Hu G, Wang C, Zhou C, Zhou W, Jia Z, Zheng B, Liu Z. Diagnostic yield and novel candidate genes by next generation sequencing in 166 children with intrahepatic cholestasis. Hepatol Int 2024; 18:661-672. [PMID: 37314652 DOI: 10.1007/s12072-023-10553-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/19/2023] [Indexed: 06/15/2023]
Abstract
BACKGROUND AND AIMS Cholestatic liver disease is a leading referral to pediatric liver transplant centers. Inherited disorders are the second most frequent cause of cholestasis in the first month of life. METHODS We retrospectively characterized the genotype and phenotype of 166 participants with intrahepatic cholestasis, and re-analyzed phenotype and whole-exome sequencing (WES) data from patients with previously undetermined genetic etiology for newly published genes and novel candidates. Functional validations of selected variants were conducted in cultured cells. RESULTS Overall, we identified disease-causing variants in 31% (52/166) of our study participants. Of the 52 individuals, 18 (35%) had metabolic liver diseases, 9 (17%) had syndromic cholestasis, 9 (17%) had progressive familial intrahepatic cholestasis, 3 (6%) had bile acid synthesis defects, 3(6%) had infantile liver failure and 10 (19%) had a phenocopy of intrahepatic cholestasis. By reverse phenotyping, we identified a de novo variant c.1883G > A in FAM111B of a case with high glutamyl transpeptidase (GGT) cholestasis. By re-analyzing WES data, two patients were newly solved, who had compound heterozygous variants in recently published genes KIF12 and USP53, respectively. Our additional search for novel candidates in unsolved WES families revealed four potential novel candidate genes (NCOA6, CCDC88B, USP24 and ATP11C), among which the patients with variants in NCOA6 and ATP11C recapitulate the cholestasis phenotype in mice models. CONCLUSIONS In a single-center pediatric cohort, we identified monogenic variants in 22 known human intrahepatic cholestasis or phenocopy genes, explaining up to 31% of the intrahepatic cholestasis patients. Our findings suggest that re-evaluating existing WES data from well-phenotyped patients on a regular basis can increase the diagnostic yield for cholestatic liver disease in children.
Collapse
Affiliation(s)
- Yucan Zheng
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Hongmei Guo
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Leilei Chen
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Weixia Cheng
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Kunlong Yan
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Zhihua Zhang
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Mei Li
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Yu Jin
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Guorui Hu
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Chunli Wang
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Chunlei Zhou
- Department of Pathology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Wei Zhou
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Zhanjun Jia
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Bixia Zheng
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, China.
| | - Zhifeng Liu
- Department of Gastroenterology, Children's Hospital of Nanjing Medical University, Nanjing, China.
| |
Collapse
|
4
|
Hong R, Tan Y, Tian X, Huang Z, Wang J, Ni H, Yang J, Bu W, Yang S, Li T, Yu F, Zhong W, Sun T, Wang X, Li D, Liu M, Yang Y, Zhou J. XIAP-mediated degradation of IFT88 disrupts HSC cilia to stimulate HSC activation and liver fibrosis. EMBO Rep 2024; 25:1055-1074. [PMID: 38351372 PMCID: PMC10933415 DOI: 10.1038/s44319-024-00092-y] [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: 12/11/2022] [Revised: 12/15/2023] [Accepted: 01/25/2024] [Indexed: 02/19/2024] Open
Abstract
Activation of hepatic stellate cells (HSCs) plays a critical role in liver fibrosis. However, the molecular basis for HSC activation remains poorly understood. Herein, we demonstrate that primary cilia are present on quiescent HSCs but exhibit a significant loss upon HSC activation which correlates with decreased levels of the ciliary protein intraflagellar transport 88 (IFT88). Ift88-knockout mice are more susceptible to chronic carbon tetrachloride-induced liver fibrosis. Mechanistic studies show that the X-linked inhibitor of apoptosis (XIAP) functions as an E3 ubiquitin ligase for IFT88. Transforming growth factor-β (TGF-β), a profibrotic factor, enhances XIAP-mediated ubiquitination of IFT88, promoting its proteasomal degradation. Blocking XIAP-mediated IFT88 degradation ablates TGF-β-induced HSC activation and liver fibrosis. These findings reveal a previously unrecognized role for ciliary homeostasis in regulating HSC activation and identify the XIAP-IFT88 axis as a potential therapeutic target for liver fibrosis.
Collapse
Affiliation(s)
- Renjie Hong
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Yanjie Tan
- Center for Cell Structure and Function, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, 250014, Jinan, China
| | - Xiaoyu Tian
- Center for Cell Structure and Function, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, 250014, Jinan, China
| | - Zhenzhou Huang
- Center for Cell Structure and Function, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, 250014, Jinan, China
| | - Jiaying Wang
- Center for Cell Structure and Function, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, 250014, Jinan, China
| | - Hua Ni
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Jia Yang
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Weiwen Bu
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Song Yang
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Te Li
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Fan Yu
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Weilong Zhong
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, 300052, Tianjin, China
| | - Tao Sun
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, 300071, Tianjin, China
| | - Xiaohong Wang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, School of Basic Medical Sciences, Tianjin Medical University, 300070, Tianjin, China
| | - Dengwen Li
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Min Liu
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China
| | - Yunfan Yang
- Department of Cell Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, 250012, Jinan, China.
| | - Jun Zhou
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, 300071, Tianjin, China.
- Center for Cell Structure and Function, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, 250014, Jinan, China.
| |
Collapse
|
5
|
Xie L, Fang Y, Chen J, Meng W, Guan Y, Gong W. TTC13 expression and STAT3 activation may form a positive feedback loop to promote ccRCC progression. PeerJ 2023; 11:e16316. [PMID: 37927783 PMCID: PMC10621595 DOI: 10.7717/peerj.16316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/28/2023] [Indexed: 11/07/2023] Open
Abstract
Background Renal cell carcinoma (RCC) originates from renal tubular epithelial cells and is mainly classified into three histological types, including clear cell renal cell carcinoma (ccRCC) which accounts for about 75% of all kidney cancers and is characterized by its strong invasiveness and poor prognosis. Hence, it is imperative to understand the mechanisms underlying the occurrence and progression of ccRCC to identify effective biomarkers for the early diagnosis and the prognosis prediction. Methods The mRNA level of TTC13 was quantified by RT-PCR, while the protein level was determined by western blot and immunohistochemistry (IHC) staining. Cell proliferation was measured by cck-8, and cell apoptosis was detected by flow cytometry. The binding of STAT3 to the promoter region of TTC13 was determined by the luciferase reporter assay and chip experiments. STAT3 nuclear translocation was assessed by immunofluorescence staining. Results We found that TTC13 was up-regulated in ccRCC, and TTC13 promoted cell proliferation as well as inhibited cell apoptosis and autophagy of ccRCC through wnt/β-catenin and IL6-JAK-STAT3 signaling pathways. Furthermore, TTC13 might play a role in the immune infiltration and immunotherapy of ccRCC. Mechanistically, STAT3 activated the transcription of TTC13 gene. Conclusions STAT3 directly regulated TTC13 expression through a positive feedback loop mechanism to promote ccRCC cell proliferation as well as reduce cell apoptosis and autophagy. These findings suggested new and effective therapeutic targets for more accurate and personalized treatment strategies.
Collapse
Affiliation(s)
- Lingling Xie
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Yu Fang
- Department of Urology, The First Affiliated Hospital of Naval Medical University (Shanghai Changhai Hospital), Shanghai, China
| | - Jianping Chen
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Wei Meng
- Department of Urology, Affiliated Hospital of Nantong University, Nantong, China
| | - Yangbo Guan
- Department of Urology, Affiliated Hospital of Nantong University, Nantong, China
| | - Wenliang Gong
- Department of Urology, The First Affiliated Hospital of Naval Medical University (Shanghai Changhai Hospital), Shanghai, China
- Department of Urology, The Third Affiliated Hospital of Naval Medical University (Shanghai Eastern Hepatobiliary Surgery Hospital), Shanghai, China
| |
Collapse
|
6
|
Fassad MR, Rumman N, Junger K, Patel MP, Thompson J, Goggin P, Ueffing M, Beyer T, Boldt K, Lucas JS, Mitchison HM. Defective airway intraflagellar transport underlies a combined motile and primary ciliopathy syndrome caused by IFT74 mutations. Hum Mol Genet 2023; 32:3090-3104. [PMID: 37555648 PMCID: PMC10586200 DOI: 10.1093/hmg/ddad132] [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: 06/23/2023] [Revised: 08/01/2023] [Indexed: 08/10/2023] Open
Abstract
Ciliopathies are inherited disorders caused by defective cilia. Mutations affecting motile cilia usually cause the chronic muco-obstructive sinopulmonary disease primary ciliary dyskinesia (PCD) and are associated with laterality defects, while a broad spectrum of early developmental as well as degenerative syndromes arise from mutations affecting signalling of primary (non-motile) cilia. Cilia assembly and functioning requires intraflagellar transport (IFT) of cargos assisted by IFT-B and IFT-A adaptor complexes. Within IFT-B, the N-termini of partner proteins IFT74 and IFT81 govern tubulin transport to build the ciliary microtubular cytoskeleton. We detected a homozygous 3-kb intragenic IFT74 deletion removing the exon 2 initiation codon and 40 N-terminal amino acids in two affected siblings. Both had clinical features of PCD with bronchiectasis, but no laterality defects. They also had retinal dysplasia and abnormal bone growth, with a narrowed thorax and short ribs, shortened long bones and digits, and abnormal skull shape. This resembles short-rib thoracic dysplasia, a skeletal ciliopathy previously linked to IFT defects in primary cilia, not motile cilia. Ciliated nasal epithelial cells collected from affected individuals had reduced numbers of shortened motile cilia with disarranged microtubules, some misorientation of the basal feet, and disrupted cilia structural and IFT protein distributions. No full-length IFT74 was expressed, only truncated forms that were consistent with N-terminal deletion and inframe translation from downstream initiation codons. In affinity purification mass spectrometry, exon 2-deleted IFT74 initiated from the nearest inframe downstream methionine 41 still interacts as part of the IFT-B complex, but only with reduced interaction levels and not with all its usual IFT-B partners. We propose that this is a hypomorphic mutation with some residual protein function retained, which gives rise to a primary skeletal ciliopathy combined with defective motile cilia and PCD.
Collapse
Affiliation(s)
- Mahmoud R Fassad
- Genetics and Genomic Medicine Research and Teaching Department, University College London, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, United Kingdom
- Department of Human Genetics, Medical Research Institute, Alexandria University, 22 El-Guish Road, El-Shatby, Alexandria 21526, Egypt
| | - Nisreen Rumman
- Department of Pediatrics, Faculty of Medicine, Makassed Hospital and Al-Quds University, East Jerusalem 91220, Palestine
- Section of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, Yale University School of Medicine, 300 Cedar St #441, New Haven, CT 06520, United States
| | - Katrin Junger
- Institute for Ophthalmic Research, Eberhard Karl University of Tübingen, Elfreide-Alhorn-Strasse 5-7, Tübingen 72076, Germany
| | - Mitali P Patel
- Genetics and Genomic Medicine Research and Teaching Department, University College London, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, United Kingdom
- MRC Prion Unit at UCL, Institute of Prion Diseases, University College London, 33 Cleveland Street, London W1W 7FF, United Kingdom
| | - James Thompson
- Primary Ciliary Dyskinesia Centre, NIHR Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, United Kingdom
- School of Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, University Road, Southampton SO17 1BJ, United Kingdom
- Biomedical Imaging Unit, University of Southampton Faculty of Medicine, University Road, Southampton SO17 1BJ, United Kingdom
| | - Patricia Goggin
- Primary Ciliary Dyskinesia Centre, NIHR Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, United Kingdom
- Biomedical Imaging Unit, University of Southampton Faculty of Medicine, University Road, Southampton SO17 1BJ, United Kingdom
| | - Marius Ueffing
- Institute for Ophthalmic Research, Eberhard Karl University of Tübingen, Elfreide-Alhorn-Strasse 5-7, Tübingen 72076, Germany
| | - Tina Beyer
- Institute for Ophthalmic Research, Eberhard Karl University of Tübingen, Elfreide-Alhorn-Strasse 5-7, Tübingen 72076, Germany
| | - Karsten Boldt
- Institute for Ophthalmic Research, Eberhard Karl University of Tübingen, Elfreide-Alhorn-Strasse 5-7, Tübingen 72076, Germany
| | - Jane S Lucas
- Primary Ciliary Dyskinesia Centre, NIHR Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, United Kingdom
- School of Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, University Road, Southampton SO17 1BJ, United Kingdom
| | - Hannah M Mitchison
- Genetics and Genomic Medicine Research and Teaching Department, University College London, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, United Kingdom
| |
Collapse
|
7
|
Waddell SH, Yao Y, Olaizola P, Walker A, Jarman EJ, Gournopanos K, Gradinaru A, Christodoulou E, Gautier P, Boerrigter MM, Cadamuro M, Fabris L, Drenth JPH, Kendall TJ, Banales JM, Khamseh A, Mill P, Boulter L. A TGFβ-ECM-integrin signaling axis drives structural reconfiguration of the bile duct to promote polycystic liver disease. Sci Transl Med 2023; 15:eabq5930. [PMID: 37703354 PMCID: PMC7615241 DOI: 10.1126/scitranslmed.abq5930] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/18/2023] [Indexed: 09/15/2023]
Abstract
The formation of multiple cysts in the liver occurs in a number of isolated monogenic diseases or multisystemic syndromes, during which bile ducts develop into fluid-filled biliary cysts. For patients with polycystic liver disease (PCLD), nonsurgical treatments are limited, and managing life-long abdominal swelling, pain, and increasing risk of cyst rupture and infection is common. We demonstrate here that loss of the primary cilium on postnatal biliary epithelial cells (via the deletion of the cilia gene Wdr35) drives ongoing pathological remodeling of the biliary tree, resulting in progressive cyst formation and growth. The development of cystic tissue requires the activation of transforming growth factor-β (TGFβ) signaling, which promotes the expression of a procystic, fibronectin-rich extracellular matrix and which itself is perceived by a changing profile of integrin receptors on the cystic epithelium. This signaling axis is conserved in liver cysts from patients with either autosomal dominant polycystic kidney disease or autosomal dominant polycystic liver disease, indicating that there are common cellular mechanisms for liver cyst growth regardless of the underlying genetic cause. Cyst number and size can be reduced by inhibiting TGFβ signaling or integrin signaling in vivo. We suggest that our findings represent a therapeutic route for patients with polycystic liver disease, most of whom would not be amenable to surgery.
Collapse
Affiliation(s)
- Scott H Waddell
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Yuelin Yao
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
- School of Informatics- University of Edinburgh- Edinburgh- UK, EH8 9AB
| | - Paula Olaizola
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
- Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute – Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain, 20014
- Centre for Inflammation Research, Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK EH16 4TJ
| | - Alexander Walker
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Edward J Jarman
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Konstantinos Gournopanos
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Andreea Gradinaru
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Ersi Christodoulou
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Philippe Gautier
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Melissa M Boerrigter
- Department of Gastroenterology and Hepatology, Radboud University, Nijmegen Medical Center- 6525 GA Nijmegen- Netherlands
| | | | - Luca Fabris
- Department of Molecular Medicine, University of Padua, 35128 Padua, Italy
- Digestive Disease Section, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Joost PH Drenth
- Department of Gastroenterology and Hepatology, Radboud University, Nijmegen Medical Center- 6525 GA Nijmegen- Netherlands
| | - Timothy J Kendall
- Centre for Inflammation Research, Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK EH16 4TJ
| | - Jesus M Banales
- Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute – Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain, 20014
- National Institute for the Study of Liver and Gastrointestinal Diseases, CIBERehd, “Instituto de Salud Carlos III”, 28029 Madrid, Spain
- Department of Biochemistry and Genetics, School of Sciences, University of Navarra, 31008 Pamplona, Spain
- IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Ava Khamseh
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
- School of Informatics- University of Edinburgh- Edinburgh- UK, EH8 9AB
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
| | - Luke Boulter
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh- Edinburgh- UK, EH4 2XU
- Cancer Research UK Scotland Centre, Institute of Genetics and Cancer, Edinburgh, UK, EH4 2XU
| |
Collapse
|
8
|
Tong L, Rao J, Yang C, Xu J, Lu Y, Zhang Y, Cang X, Xie S, Mao J, Jiang P. Mutational burden of XPNPEP3 leads to defects in mitochondrial complex I and cilia in NPHPL1. iScience 2023; 26:107446. [PMID: 37599822 PMCID: PMC10432713 DOI: 10.1016/j.isci.2023.107446] [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: 01/11/2023] [Revised: 05/29/2023] [Accepted: 07/18/2023] [Indexed: 08/22/2023] Open
Abstract
Nephronophthisis-like nephropathy-1 (NPHPL1) is a rare ciliopathy, caused by mutations of XPNPEP3. Despite a well-described monogenic etiology, the pathogenesis of XPNPEP3 associated with mitochondrial and ciliary function remains elusive. Here, we identified novel compound heterozygous mutations in NPHPL1 patients with renal lesion only or with extra bone cysts together. Patient-derived lymphoblasts carrying c.634G>A and c.761G>T together exhibit elevated mitochondrial XPNPEP3 levels via the reduction of mRNA degradation, leading to mitochondrial dysfunction in both urine tubular epithelial cells and lymphoblasts from patient. Mitochondrial XPNPEP3 was co-immunoprecipitated with respiratory chain complex I and was required for the stability and activity of complex I. Deletion of Xpnpep3 in mice resulted in lower activity of complex I, elongated primary cilium, and predisposition to tubular dilation and fibrosis under stress. Our findings provide valuable insights into the mitochondrial functions involved in the pathogenesis of NPHP.
Collapse
Affiliation(s)
- Lingxiao Tong
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
| | - Jia Rao
- Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of China, Shanghai, China
| | - Chenxi Yang
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Jie Xu
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
| | - Yijun Lu
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Yuchen Zhang
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaohui Cang
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Shanshan Xie
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
| | - Jianhua Mao
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Zhejiang Key Laboratory for Neonatal Diseases, The Children’s Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Pingping Jiang
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| |
Collapse
|
9
|
Bakey Z, Cabrera OA, Hoefele J, Antony D, Wu K, Stuck MW, Micha D, Eguether T, Smith AO, van der Wel NN, Wagner M, Strittmatter L, Beales PL, Jonassen JA, Thiffault I, Cadieux-Dion M, Boyes L, Sharif S, Tüysüz B, Dunstheimer D, Niessen HWM, Devine W, Lo CW, Mitchison HM, Schmidts M, Pazour GJ. IFT74 variants cause skeletal ciliopathy and motile cilia defects in mice and humans. PLoS Genet 2023; 19:e1010796. [PMID: 37315079 DOI: 10.1371/journal.pgen.1010796] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/23/2023] [Indexed: 06/16/2023] Open
Abstract
Motile and non-motile cilia play critical roles in mammalian development and health. These organelles are composed of a 1000 or more unique proteins, but their assembly depends entirely on proteins synthesized in the cell body and transported into the cilium by intraflagellar transport (IFT). In mammals, malfunction of non-motile cilia due to IFT dysfunction results in complex developmental phenotypes that affect most organs. In contrast, disruption of motile cilia function causes subfertility, disruption of the left-right body axis, and recurrent airway infections with progressive lung damage. In this work, we characterize allele specific phenotypes resulting from IFT74 dysfunction in human and mice. We identified two families carrying a deletion encompassing IFT74 exon 2, the first coding exon, resulting in a protein lacking the first 40 amino acids and two individuals carrying biallelic splice site mutations. Homozygous exon 2 deletion cases presented a ciliary chondrodysplasia with narrow thorax and progressive growth retardation along with a mucociliary clearance disorder phenotype with severely shorted cilia. Splice site variants resulted in a lethal skeletal chondrodysplasia phenotype. In mice, removal of the first 40 amino acids likewise results in a motile cilia phenotype but with little effect on primary cilia structure. Mice carrying this allele are born alive but are growth restricted and developed hydrocephaly in the first month of life. In contrast, a strong, likely null, allele of Ift74 in mouse completely blocks ciliary assembly and causes severe heart defects and midgestational lethality. In vitro studies suggest that the first 40 amino acids of IFT74 are dispensable for binding of other IFT subunits but are important for tubulin binding. Higher demands on tubulin transport in motile cilia compared to primary cilia resulting from increased mechanical stress and repair needs could account for the motile cilia phenotype observed in human and mice.
Collapse
Affiliation(s)
- Zeineb Bakey
- Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, Freiburg, Germany
- Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences (RIMLS), Nijmegen, The Netherlands
| | - Oscar A Cabrera
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Biotech II, Worcester, Massachusetts, United States of America
| | - Julia Hoefele
- Institute for Human Genetics, Technical University Munich (TUM), School of Medicine, Munich, Germany
| | - Dinu Antony
- Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, Freiburg, Germany
- Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences (RIMLS), Nijmegen, The Netherlands
| | - Kaman Wu
- Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences (RIMLS), Nijmegen, The Netherlands
| | - Michael W Stuck
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Biotech II, Worcester, Massachusetts, United States of America
| | - Dimitra Micha
- Department of Human Genetics, Amsterdam Movement Sciences, Amsterdam UMC, Amsterdam, The Netherlands
| | - Thibaut Eguether
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Biotech II, Worcester, Massachusetts, United States of America
| | - Abigail O Smith
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Biotech II, Worcester, Massachusetts, United States of America
| | - Nicole N van der Wel
- Electron microscopy Center Amsterdam, Department of Medical Biology, VUMC, Amsterdam, The Netherlands
| | - Matias Wagner
- Institute for Human Genetics, Technical University Munich (TUM), School of Medicine, Munich, Germany
| | - Lara Strittmatter
- Electron Microscopy Core, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Philip L Beales
- Genetics and Genomic Medicine Programme, University College London, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Julie A Jonassen
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Isabelle Thiffault
- Genomic Medicine Center, Children's Mercy Hospital, Kansas City, Missouri, United States of America
| | - Maxime Cadieux-Dion
- Genomic Medicine Center, Children's Mercy Hospital, Kansas City, Missouri, United States of America
| | - Laura Boyes
- West Midlands Genomic Medicine Hub, Birmingham Women's Hospital, Birmingham, United Kingdom
| | - Saba Sharif
- West Midlands Genomic Medicine Hub, Birmingham Women's Hospital, Birmingham, United Kingdom
| | - Beyhan Tüysüz
- Department of Pediatrics, Division of Pediatric Genetics, Cerrahpasa Medical Faculty, University-Cerrahpasa, Istanbul, Turkey
| | - Desiree Dunstheimer
- Center for Pediatrics and Adolescent Medicine, University Hospital Augsburg, Augsburg, Germany
| | - Hans W M Niessen
- Department of Pathology, Amsterdam University Medical Center (AUMC), Amsterdam, The Netherlands
| | - William Devine
- Department of Developmental Biology, University of Pittsburgh, 8111 Rangos Research Center, Pittsburgh, Pennsylvania, United States of America
| | - Cecilia W Lo
- Department of Developmental Biology, University of Pittsburgh, 8111 Rangos Research Center, Pittsburgh, Pennsylvania, United States of America
| | - Hannah M Mitchison
- Genetics and Genomic Medicine Programme, University College London, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Miriam Schmidts
- Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, Freiburg, Germany
- Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences (RIMLS), Nijmegen, The Netherlands
- CIBSS-Center for Integrative Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Biotech II, Worcester, Massachusetts, United States of America
| |
Collapse
|
10
|
Bakey Z, Cabrera OA, Hoefele J, Antony D, Wu K, Stuck MW, Micha D, Eguether T, Smith AO, van der Wel NN, Wagner M, Strittmatter L, Beales PL, Jonassen JA, Thiffault I, Cadieux-Dion M, Boyes L, Sharif S, Tüysüz B, Dunstheimer D, Niessen HW, Devine W, Lo CW, Mitchison HM, Schmidts M, Pazour GJ. IFT74 variants cause skeletal ciliopathy and motile cilia defects in mice and humans. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.02.23.23286106. [PMID: 36865301 PMCID: PMC9980244 DOI: 10.1101/2023.02.23.23286106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Motile and non-motile cilia are critical to mammalian development and health. Assembly of these organelles depends on proteins synthesized in the cell body and transported into the cilium by intraflagellar transport (IFT). A series of human and mouse IFT74 variants were studied to understand the function of this IFT subunit. Humans missing exon 2, which codes for the first 40 residues, presented an unusual combination of ciliary chondrodysplasia and mucociliary clearance disorders while individuals carrying biallelic splice site variants developed a lethal skeletal chondrodysplasia. In mice, variants thought to remove all Ift74 function, completely block ciliary assembly and result in midgestational lethality. A mouse allele that removes the first 40 amino acids, analogous to the human exon 2 deletion, results in a motile cilia phenotype with mild skeletal abnormalities. In vitro studies suggest that the first 40 amino acids of IFT74 are dispensable for binding of other IFT subunits but are important for tubulin binding. Higher demands on tubulin transport in motile cilia compared to primary cilia could account for the motile cilia phenotype observed in human and mice.
Collapse
|
11
|
Kelly DE, Ramdas S, Ma R, Rawlings-Goss RA, Grant GR, Ranciaro A, Hirbo JB, Beggs W, Yeager M, Chanock S, Nyambo TB, Omar SA, Woldemeskel D, Belay G, Li H, Brown CD, Tishkoff SA. The genetic and evolutionary basis of gene expression variation in East Africans. Genome Biol 2023; 24:35. [PMID: 36829244 PMCID: PMC9951478 DOI: 10.1186/s13059-023-02874-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 02/13/2023] [Indexed: 02/26/2023] Open
Abstract
BACKGROUND Mapping of quantitative trait loci (QTL) associated with molecular phenotypes is a powerful approach for identifying the genes and molecular mechanisms underlying human traits and diseases, though most studies have focused on individuals of European descent. While important progress has been made to study a greater diversity of human populations, many groups remain unstudied, particularly among indigenous populations within Africa. To better understand the genetics of gene regulation in East Africans, we perform expression and splicing QTL mapping in whole blood from a cohort of 162 diverse Africans from Ethiopia and Tanzania. We assess replication of these QTLs in cohorts of predominantly European ancestry and identify candidate genes under selection in human populations. RESULTS We find the gene regulatory architecture of African and non-African populations is broadly shared, though there is a considerable amount of variation at individual loci across populations. Comparing our analyses to an equivalently sized cohort of European Americans, we find that QTL mapping in Africans improves the detection of expression QTLs and fine-mapping of causal variation. Integrating our QTL scans with signatures of natural selection, we find several genes related to immunity and metabolism that are highly differentiated between Africans and non-Africans, as well as a gene associated with pigmentation. CONCLUSION Extending QTL mapping studies beyond European ancestry, particularly to diverse indigenous populations, is vital for a complete understanding of the genetic architecture of human traits and can reveal novel functional variation underlying human traits and disease.
Collapse
Affiliation(s)
- Derek E Kelly
- Genomics and Computational Biology, University of Pennsylvania, Philadelphia, PA, USA
- Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Shweta Ramdas
- Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Rong Ma
- Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | | | - Jibril B Hirbo
- Department of Medicine, Division of Genetic Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - William Beggs
- Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Meredith Yeager
- Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Stephen Chanock
- Division of Cancer Epidemiology and Genetics, National Institutes of Health, Rockville, MD, USA
| | - Thomas B Nyambo
- Department of Biochemistry, Kampala International University in Tanzania, Dar Es Salaam, Tanzania
| | - Sabah A Omar
- Center for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Dawit Woldemeskel
- Microbial Cellular and Molecular Biology Department, Addis Ababa University, Addis Ababa, Ethiopia
| | - Gurja Belay
- Microbial Cellular and Molecular Biology Department, Addis Ababa University, Addis Ababa, Ethiopia
| | - Hongzhe Li
- Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Christopher D Brown
- Genomics and Computational Biology, University of Pennsylvania, Philadelphia, PA, USA
- Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Sarah A Tishkoff
- Genetics, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Biology, University of Pennsylvania, Philadelphia, USA.
| |
Collapse
|
12
|
Nakazato R, Otani H, Ijaz F, Ikegami K. Time-lapse imaging of primary cilium behavior with physiological expression of fluorescent ciliary proteins. Methods Cell Biol 2023; 175:45-68. [PMID: 36967145 DOI: 10.1016/bs.mcb.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Almost all cell types of mammals have a small protrusion named a primary cilium on their surface. Primary cilia are enriched by cilia-specific ion channels and G-protein-coupled receptors. They are known to regulate various cellular functions that contribute to the development and homeostasis of living organisms by receiving extracellular signals and transfusing them to the cell body. All functions are performed when the structure of the primary cilia is maintained properly. Abnormalities in primary cilia or their signaling can lead to a collection of diseases in various organs called ciliopathies. The primary cilium is dynamic, static, or fixed. The length of primary cilia varies as the cell cycle progresses and is also altered by extracellular stimuli. Ligand binding to cilia-specific receptors is also known to alter the length. Thus, there is a need for a method to study the morphological changes of the primary cilium in a time-dependent manner, especially under stimuli or mechanical shocks. Time-lapse imaging of primary cilia is one of the most powerful methods to capture the time-dependent behavior of primary cilia. Overexpression of ciliary proteins fused to fluorescent proteins is commonly used for the time-lapse imaging of primary cilia. However, overexpression has drawbacks in terms of artifacts. In addition, the time-lapse imaging of the tiny primary cilia requires some technical tricks. Here, we present a detailed description of the methods for time-lapse imaging of primary cilium, from the generation of cell lines that stably express fluorescent protein-labeled cilia-localized proteins at the physiological level to image analysis, including quantification through image acquisition.
Collapse
|
13
|
Chen W, Wang F, Zeng W, Zhang X, Shen L, Zhang Y, Zhou X. Biallelic mutations of TTC12 and TTC21B were identified in Chinese patients with multisystem ciliopathy syndromes. Hum Genomics 2022; 16:48. [PMID: 36273201 PMCID: PMC9587637 DOI: 10.1186/s40246-022-00421-z] [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] [Received: 07/04/2022] [Accepted: 10/12/2022] [Indexed: 12/04/2022] Open
Abstract
Background Abnormalities in cilia ultrastructure and function lead to a range of human phenotypes termed ciliopathies. Many tetratricopeptide repeat domain (TTC) family members have been reported to play critical roles in cilium organization and function.
Results Here, we describe five unrelated family trios with multisystem ciliopathy syndromes, including situs abnormality, complex congenital heart disease, nephronophthisis or neonatal cholestasis. Through whole-exome sequencing and Sanger sequencing confirmation, we identified compound heterozygous mutations of TTC12 and TTC21B in six affected individuals of Chinese origin. These nonsynonymous mutations affected highly conserved residues and were consistently predicted to be pathogenic. Furthermore, ex vivo cDNA amplification demonstrated that homozygous c.1464 + 2 T > C of TTC12 would cause a whole exon 16 skipping. Both mRNA and protein levels of TTC12 were significantly downregulated in the cells derived from the patient carrying TTC12 mutation c.1464 + 2 T > C by real-time qPCR and immunofluorescence assays when compared with two healthy controls. Transmission electron microscopy analysis further identified ultrastructural defects of the inner dynein arms in this patient. Finally, the effect of TTC12 deficiency on cardiac LR patterning was recapitulated by employing a morpholino-mediated knockdown of ttc12 in zebrafish. Conclusions To the best of our knowledge, this is the first study reporting the association between TTC12 variants and ciliopathies in a Chinese population. In addition to nephronophthisis and laterality defects, our findings demonstrated that TTC21B should also be considered a candidate gene for biliary ciliopathy, such as TTC26, which further expands the phenotypic spectrum of TTC21B deficiency in humans. Supplementary Information The online version contains supplementary material available at 10.1186/s40246-022-00421-z.
Collapse
Affiliation(s)
- Weicheng Chen
- Obstetrics and Gynecology Hospital of Fudan University, Pediatric Cardiovascular Center at Children's Hospital of Fudan University, Fudan University Shanghai Medical College, Shanghai, 200011, China
| | - Feifei Wang
- Obstetrics and Gynecology Hospital of Fudan University, Pediatric Cardiovascular Center at Children's Hospital of Fudan University, Fudan University Shanghai Medical College, Shanghai, 200011, China
| | - Weijia Zeng
- State Key Lab of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Xinyan Zhang
- Obstetrics and Gynecology Hospital of Fudan University, Pediatric Cardiovascular Center at Children's Hospital of Fudan University, Fudan University Shanghai Medical College, Shanghai, 200011, China
| | - Libing Shen
- International Human Phenome Institutes (IHPI), Shanghai, 200433, China
| | - Yuan Zhang
- Department of Assisted Reproduction, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 201204, China. .,, Shanghai, China.
| | - Xiangyu Zhou
- Obstetrics and Gynecology Hospital of Fudan University, Pediatric Cardiovascular Center at Children's Hospital of Fudan University, Fudan University Shanghai Medical College, Shanghai, 200011, China. .,Department of Assisted Reproduction, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 201204, China. .,, Shanghai, China.
| |
Collapse
|
14
|
Shamseldin HE, AlAbdi L, Maddirevula S, Alsaif HS, Alzahrani F, Ewida N, Hashem M, Abdulwahab F, Abuyousef O, Kuwahara H, Gao X, Alkuraya FS. Lethal variants in humans: lessons learned from a large molecular autopsy cohort. Genome Med 2021; 13:161. [PMID: 34645488 PMCID: PMC8511862 DOI: 10.1186/s13073-021-00973-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 09/17/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Molecular autopsy refers to DNA-based identification of the cause of death. Despite recent attempts to broaden its scope, the term remains typically reserved to sudden unexplained death in young adults. In this study, we aim to showcase the utility of molecular autopsy in defining lethal variants in humans. METHODS We describe our experience with a cohort of 481 cases in whom the cause of premature death was investigated using DNA from the index or relatives (molecular autopsy by proxy). Molecular autopsy tool was typically exome sequencing although some were investigated using targeted approaches in the earlier stages of the study; these include positional mapping, targeted gene sequencing, chromosomal microarray, and gene panels. RESULTS The study includes 449 cases from consanguineous families and 141 lacked family history (simplex). The age range was embryos to 18 years. A likely causal variant (pathogenic/likely pathogenic) was identified in 63.8% (307/481), a much higher yield compared to the general diagnostic yield (43%) from the same population. The predominance of recessive lethal alleles allowed us to implement molecular autopsy by proxy in 55 couples, and the yield was similarly high (63.6%). We also note the occurrence of biallelic lethal forms of typically non-lethal dominant disorders, sometimes representing a novel bona fide biallelic recessive disease trait. Forty-six disease genes with no OMIM phenotype were identified in the course of this study. The presented data support the candidacy of two other previously reported novel disease genes (FAAH2 and MSN). The focus on lethal phenotypes revealed many examples of interesting phenotypic expansion as well as remarkable variability in clinical presentation. Furthermore, important insights into population genetics and variant interpretation are highlighted based on the results. CONCLUSIONS Molecular autopsy, broadly defined, proved to be a helpful clinical approach that provides unique insights into lethal variants and the clinical annotation of the human genome.
Collapse
Affiliation(s)
- Hanan E Shamseldin
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Lama AlAbdi
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Sateesh Maddirevula
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Hessa S Alsaif
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- Center of Excellence for Biomedicine, King Abdulaziz City for Science and Technology, Riyadh, 12354, Saudi Arabia
| | - Fatema Alzahrani
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Nour Ewida
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mais Hashem
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Firdous Abdulwahab
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Omar Abuyousef
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Hiroyuki Kuwahara
- Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Xin Gao
- Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Fowzan S Alkuraya
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
| |
Collapse
|
15
|
Wang W, Pottorf TS, Wang HH, Dong R, Kavanaugh MA, Cornelius JT, Dennis KL, Apte U, Pritchard MT, Sharma M, Tran PV. IFT-A deficiency in juvenile mice impairs biliary development and exacerbates ADPKD liver disease. J Pathol 2021; 254:289-302. [PMID: 33900625 DOI: 10.1002/path.5685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 04/16/2021] [Indexed: 02/06/2023]
Abstract
Polycystic liver disease (PLD) is characterized by the growth of numerous biliary cysts and presents in patients with autosomal dominant polycystic kidney disease (ADPKD), causing significant morbidity. Interestingly, deletion of intraflagellar transport-B (IFT-B) complex genes in adult mouse models of ADPKD attenuates the severity of PKD and PLD. Here we examine the role of deletion of an IFT-A gene, Thm1, in PLD of juvenile and adult Pkd2 conditional knockout mice. Perinatal deletion of Thm1 resulted in disorganized and expanded biliary regions, biliary fibrosis, increased serum bile acids, and a shortened primary cilium on cytokeratin 19+ (CK19+) epithelial cells. In contrast, perinatal deletion of Pkd2 caused PLD, with multiple CK19+ epithelial cell-lined cysts, fibrosis, lengthened primary cilia, and increased Notch and ERK signaling. Perinatal deletion of Thm1 in Pkd2 conditional knockout mice increased hepatomegaly, liver necrosis, as well as serum bilirubin and bile acid levels, indicating enhanced liver disease severity. In contrast to effects in the developing liver, deletion of Thm1 alone in adult mice did not cause a biliary phenotype. Combined deletion of Pkd2 and Thm1 caused variable hepatic cystogenesis at 4 months of age, but differences in hepatic cystogenesis between Pkd2- and Pkd2;Thm1 knockout mice were not observed by 6 months of age. Similar to juvenile PLD, Notch and ERK signaling were increased in adult Pkd2 conditional knockout cyst-lining epithelial cells. Taken together, Thm1 is required for biliary tract development, and proper biliary development restricts PLD severity. Unlike IFT-B genes, Thm1 does not markedly attenuate hepatic cystogenesis, suggesting differences in regulation of signaling and cystogenic processes in the liver by IFT-B and -A. Notably, increased Notch signaling in cyst-lining epithelial cells may indicate that aberrant activation of this pathway promotes hepatic cystogenesis, presenting as a novel potential therapeutic target. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Wei Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Tana S Pottorf
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Henry H Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Ruochen Dong
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Matthew A Kavanaugh
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Joseph T Cornelius
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Katie L Dennis
- Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS, USA
| | - Udayan Apte
- Department of Pharmacology, Toxicology and Therapeutics, The Liver Center, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Michele T Pritchard
- Department of Pharmacology, Toxicology and Therapeutics, The Liver Center, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Madhulika Sharma
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Pamela V Tran
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| |
Collapse
|
16
|
Wang W, Jack BM, Wang HH, Kavanaugh MA, Maser RL, Tran PV. Intraflagellar Transport Proteins as Regulators of Primary Cilia Length. Front Cell Dev Biol 2021; 9:661350. [PMID: 34095126 PMCID: PMC8170031 DOI: 10.3389/fcell.2021.661350] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 04/06/2021] [Indexed: 12/21/2022] Open
Abstract
Primary cilia are small, antenna-like organelles that detect and transduce chemical and mechanical cues in the extracellular environment, regulating cell behavior and, in turn, tissue development and homeostasis. Primary cilia are assembled via intraflagellar transport (IFT), which traffics protein cargo bidirectionally along a microtubular axoneme. Ranging from 1 to 10 μm long, these organelles typically reach a characteristic length dependent on cell type, likely for optimum fulfillment of their specific roles. The importance of an optimal cilia length is underscored by the findings that perturbation of cilia length can be observed in a number of cilia-related diseases. Thus, elucidating mechanisms of cilia length regulation is important for understanding the pathobiology of ciliary diseases. Since cilia assembly/disassembly regulate cilia length, we review the roles of IFT in processes that affect cilia assembly/disassembly, including ciliary transport of structural and membrane proteins, ectocytosis, and tubulin posttranslational modification. Additionally, since the environment of a cell influences cilia length, we also review the various stimuli encountered by renal epithelia in healthy and diseased states that alter cilia length and IFT.
Collapse
Affiliation(s)
- Wei Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Brittany M Jack
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Henry H Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Matthew A Kavanaugh
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Robin L Maser
- Department of Clinical Laboratory Sciences, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Pamela V Tran
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| |
Collapse
|
17
|
Alfadhel M, Umair M, Almuzzaini B, Asiri A, Al Tuwaijri A, Alhamoudi K, Alyafee Y, Al-Owain M. Identification of the TTC26 Splice Variant in a Novel Complex Ciliopathy Syndrome with Biliary, Renal, Neurological, and Skeletal Manifestations. Mol Syndromol 2021; 12:133-140. [PMID: 34177428 DOI: 10.1159/000513829] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 12/16/2020] [Indexed: 12/27/2022] Open
Abstract
Ciliopathies constitute heterogeneous disorders that result from mutations in ciliary proteins. These proteins play an important role in the development of organs, physiology, and signaling pathways, and sequence variations in the genes encoding these proteins are associated with multisystem disorders. In this study, we describe a severe ciliopathy disorder that segregates in an autosomal recessive manner in a nonconsanguineous Saudi family. The proband exhibited features such as cholestasis, cystic dilatation of intrahepatic biliary ducts, diabetes insipidus, dysmorphic facial features, optic atrophy, pituitary hypoplasia, hydrocephalus, aqueductal stenosis, hyperextensible knee joints, bilateral knee dislocation, polydactyly, and syndactyly. Whole-genome sequencing and Sanger sequencing revealed a homozygous splice site variant (c.4-1G>C; NM_024926.3) in the tetratricopeptide repeat domain 26 (TTC26) gene located in chromosome 7q34, which cosegregated perfectly with the disease phenotype. qRT-PCR revealed a substantial decrease in the expression of the TTC26 gene as compared to the normal control, suggesting the pathogenicity of the identified variant. This report further strengthens the evidence that homozygous variants in the TTC26 gene cause severe ciliopathies with diverse phenotypes. We named this newly characterized condition as BRENS syndrome, which stands for biliary, renal, neurological, and skeletal features.
Collapse
Affiliation(s)
- Majid Alfadhel
- Medical Genomics Research Department, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia.,King Saud Bin Abdulaziz University for Health Sciences, MNGH, Riyadh, Saudi Arabia.,Division of Genetics, Department of Pediatrics, King Abdullah Specialized Children's Hospital, King Abdulaziz Medical City, Riyadh, Saudi Arabia
| | - Muhammad Umair
- Medical Genomics Research Department, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia.,King Saud Bin Abdulaziz University for Health Sciences, MNGH, Riyadh, Saudi Arabia
| | - Bader Almuzzaini
- Medical Genomics Research Department, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia.,King Saud Bin Abdulaziz University for Health Sciences, MNGH, Riyadh, Saudi Arabia
| | - Abdulaziz Asiri
- Medical Genomics Research Department, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia.,Faculty of Applied Medical Sciences, University of Bisha, Bisha, Saudi Arabia
| | - Abeer Al Tuwaijri
- Medical Genomics Research Department, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia.,King Saud Bin Abdulaziz University for Health Sciences, MNGH, Riyadh, Saudi Arabia
| | - Khaloud Alhamoudi
- Medical Genomics Research Department, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia.,King Saud Bin Abdulaziz University for Health Sciences, MNGH, Riyadh, Saudi Arabia
| | - Yusra Alyafee
- Medical Genomics Research Department, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia.,King Saud Bin Abdulaziz University for Health Sciences, MNGH, Riyadh, Saudi Arabia
| | - Mohammed Al-Owain
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| |
Collapse
|
18
|
Mandato C, Siano MA, Nazzaro L, Gelzo M, Francalanci P, Rizzo F, D'Agostino Y, Morleo M, Brillante S, Weisz A, Franco B, Vajro P. A ZFYVE19 gene mutation associated with neonatal cholestasis and cilia dysfunction: case report with a novel pathogenic variant. Orphanet J Rare Dis 2021; 16:179. [PMID: 33853651 PMCID: PMC8048179 DOI: 10.1186/s13023-021-01775-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 03/09/2021] [Indexed: 11/10/2022] Open
Abstract
Background ZFYVE19 (Zinc Finger FYVE-Type Containing 19) mutations have most recently been associated to a novel type of high gamma-glutamyl transpeptidase (GGT), non-syndromic, neonatal-onset intrahepatic chronic cholestasis possibly associated to cilia dysfunction. Herein, we report a new case with further studies of whole exome sequencing (WES) and immunofluorescence in primary cilia of her cultured fibroblasts which confirm the observation. Results A now 5-year-old girl born to clinically healthy consanguineous Moroccan parents was assessed at 59 days of life due to severe cholestatic jaundice with increased serum bile acids and GGT, and preserved hepatocellular synthetic function. Despite fibrosis/cirrhosis and biliary ducts proliferation on liver biopsy suggested an extrahepatic biliary obstacle, normal intra-operatory cholangiography excluded biliary atresia. Under choleretic treatment, she maintained a clinically stable anicteric cholestasis but developped hyperlipidemia. After exclusion of the main causes of cholestasis by multiple tests, abnormal concentrations of sterols and WES led to a diagnosis of hereditary sitosterolemia (OMIM #618666), likely unrelated to her cholestasis. Further sequencing investigation revealed a homozygous non-sense mutation (p.Arg223Ter) in ZFYVE19 leading to a 222 aa truncated protein and present in both heterozygous parents. Immunofluorescence analysis of primary cilia on cultured skin fibroblasts showed a ciliary phenotype mainly defined by fragmented cilia and centrioles abnormalities. Conclusions Our findings are consistent with and expands the recent evidence linking ZFYVE19 to a novel, likely non-syndromic, high GGT-PFIC phenotype with neonatal onset. Due to the possible role of ZFYVE19 in cilia function and the unprecedented coexistence of a coincidental hereditary sterol disorder in our case, continuous monitoring will be necessary to substantiate type of liver disease progression and/or possible emergence of a multisystemic involvement. What mentioned above confirms that the application of WES in children with undiagnosed cholestasis may lead to the identification of new causative genes, widening the knowledge on the pathophysiology. Supplementary Information The online version contains supplementary material available at 10.1186/s13023-021-01775-8.
Collapse
Affiliation(s)
- Claudia Mandato
- Department of Pediatrics, Santobono-Pausilipon Children's Hospital, Naples, Italy
| | - Maria Anna Siano
- Postgraduate School of Pediatrics Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Via Allende, 84081, Baronissi, (SA), Italy
| | - Lucia Nazzaro
- Pediatric Clinic, "SS. Giovanni Di Dio and Ruggi D'Aragona" University of Salerno Hospital, Via San Leonardo, 84131, Salerno, Italy
| | - Monica Gelzo
- Department of Molecular Medicine and Medical Biotechnology, Faculty of Medicine, University of Naples Federico II, Naples, Italy
| | - Paola Francalanci
- Pathology Unit. Department of Laboratories, IRCCS Bambino Gesù Pediatric Hospital, Rome, Italy
| | - Francesca Rizzo
- Medical Genomics Program, "SS. Giovanni Di Dio and Ruggi D'Aragona" University of Salerno Hospital, Salerno, Italy.,Laboratory of Molecular Medicine and Genomics, Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno and Genome Research Center for Health (CRGS), Baronissi, (SA), Italy
| | - Ylenia D'Agostino
- Laboratory of Molecular Medicine and Genomics, Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno and Genome Research Center for Health (CRGS), Baronissi, (SA), Italy
| | - Manuela Morleo
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Simona Brillante
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Alessandro Weisz
- Medical Genomics Program, "SS. Giovanni Di Dio and Ruggi D'Aragona" University of Salerno Hospital, Salerno, Italy.,Laboratory of Molecular Medicine and Genomics, Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno and Genome Research Center for Health (CRGS), Baronissi, (SA), Italy
| | - Brunella Franco
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy.,Medical Genetics, Department of Medical Translational Science, Faculty of Medicine, University of Naples "Federico II", Naples, Italy
| | - Pietro Vajro
- Postgraduate School of Pediatrics Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Via Allende, 84081, Baronissi, (SA), Italy. .,Pediatric Clinic, "SS. Giovanni Di Dio and Ruggi D'Aragona" University of Salerno Hospital, Via San Leonardo, 84131, Salerno, Italy.
| |
Collapse
|
19
|
Allard BA, Wang W, Pottorf TS, Mumtaz H, Jack BM, Wang HH, Silva LM, Jacobs DT, Wang J, Bumann EE, Tran PV. Thm2 interacts with paralog, Thm1, and sensitizes to Hedgehog signaling in postnatal skeletogenesis. Cell Mol Life Sci 2021; 78:3743-3762. [PMID: 33683377 DOI: 10.1007/s00018-021-03806-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 02/06/2021] [Accepted: 02/27/2021] [Indexed: 11/25/2022]
Abstract
Mutations in the intraflagellar transport-A (IFT-A) gene, THM1, have been identified in skeletal ciliopathies. Here, we report a genetic interaction between Thm1, and its paralog, Thm2, in postnatal skeletogenesis. THM2 localizes to primary cilia, but Thm2 deficiency does not affect ciliogenesis and Thm2-null mice survive into adulthood. However, by postnatal day 14, Thm2-/-; Thm1aln/+ mice exhibit small stature and small mandible. Radiography and microcomputed tomography reveal Thm2-/-; Thm1aln/+ tibia are less opaque and have reduced cortical and trabecular bone mineral density. In the mutant tibial growth plate, the proliferation zone is expanded and the hypertrophic zone is diminished, indicating impaired chondrocyte differentiation. Additionally, mutant growth plate chondrocytes show increased Hedgehog signaling. Yet deletion of one allele of Gli2, a major transcriptional activator of the Hedgehog pathway, exacerbated the Thm2-/-; Thm1aln/+ small phenotype, and further revealed that Thm2-/-; Gli2+/- mice have small stature. In Thm2-/-; Thm1aln/+ primary osteoblasts, a Hedgehog signaling defect was not detected, but bone nodule formation was markedly impaired. This indicates a signaling pathway is altered, and we propose that this pathway may potentially interact with Gli2. Together, our data reveal that loss of Thm2 with one allele of Thm1, Gli2, or both, present new IFT mouse models of osteochondrodysplasia. Our data also suggest Thm2 as a modifier of Hedgehog signaling in postnatal skeletal development.
Collapse
Affiliation(s)
- Bailey A Allard
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA
| | - Wei Wang
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA
| | - Tana S Pottorf
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA
| | - Hammad Mumtaz
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO, USA
| | - Brittany M Jack
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA
| | - Henry H Wang
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA
| | - Luciane M Silva
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA
| | - Damon T Jacobs
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA
| | - Jinxi Wang
- Department of Orthopedic Surgery, Medical Center, University of Kansas, Kansas City, KS, 66160, USA
| | - Erin E Bumann
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO, USA
| | - Pamela V Tran
- Department of Anatomy and Cell Biology, Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., MS #3038, Kansas City, KS, 66160, USA.
| |
Collapse
|
20
|
Zlotogora J. Forty-seven pathogenic variants causing autosomal recessive disorders are shared by Israeli and Saudi Arabian Arabs. Clin Genet 2021; 99:818-822. [PMID: 33543475 DOI: 10.1111/cge.13938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 01/24/2021] [Accepted: 02/01/2021] [Indexed: 11/30/2022]
Abstract
Several autosomal recessive disorders that are found among Arabs in Israel were also reported in Saudi Arabia. In a sytematic review of all the variants responsible for autosomal recessive disorders among Muslim Arabs Israel and in Saudi Arabia, 47 shared variants were found, many being known founder variants in both populations. Among the 21 shared variants that were reported among Bedouins 14 were founder variants representing 14% founder/assumed founder variants known in the Bedouins. Many of the common variants are ancient having a Bedouin origin probably linked to the migration from the Saudi Peninsula. It is probable that a similar phenomenon occurred along the route of the Bedouin migrations and indeed some of these variants are present in the corresponding populations.
Collapse
Affiliation(s)
- Joël Zlotogora
- Hadassah-Hebrew University Medical School, Jerusalem, Israel
| |
Collapse
|
21
|
Abstract
Pituitary stalk interruption syndrome (PSIS) is a distinct developmental defect of the pituitary gland identified by magnetic resonance imaging and characterized by a thin, interrupted, attenuated or absent pituitary stalk, hypoplasia or aplasia of the adenohypophysis, and an ectopic posterior pituitary. The precise etiology of PSIS still remains elusive or incompletely confirmed in most cases. Adverse perinatal events, including breech delivery and hypoxia, were initially proposed as the underlying mechanism affecting the hypothalamic-pituitary axis. Nevertheless, recent findings have uncovered a wide variety of PSIS-associated molecular defects in genes involved in pituitary development, holoprosencephaly (HPE), neural development, and other important cellular processes such as cilia function. The application of whole exome sequencing (WES) in relatively large cohorts has identified an expanded pool of potential candidate genes, mostly related to the Wnt, Notch, and sonic hedgehog signaling pathways that regulate pituitary growth and development during embryogenesis. Importantly, WES has revealed coexisting pathogenic variants in a significant number of patients; therefore, pointing to a multigenic origin and inheritance pattern of PSIS. The disorder is characterized by inter- and intrafamilial variability and incomplete or variable penetrance. Overall, PSIS is currently viewed as a mild form of an expanded HPE spectrum. The wide and complex clinical manifestations include evolving pituitary hormone deficiencies (with variable timing of onset and progression) and extrapituitary malformations. Severe and life-threatening symptomatology is observed in a subset of patients with complete pituitary hormone deficiency during the neonatal period. Nevertheless, most patients are referred later in childhood for growth retardation. Prompt and appropriate hormone substitution therapy constitutes the cornerstone of treatment. Further studies are needed to uncover the etiopathogenesis of PSIS.
Collapse
Affiliation(s)
- Antonis Voutetakis
- Department of Pediatrics, School of Medicine, Democritus University of Thrace, Alexandroupolis, Thrace, Greece.
| |
Collapse
|
22
|
Alhebbi H, Peer-Zada AA, Al-Hussaini AA, Algubaisi S, Albassami A, AlMasri N, Alrusayni Y, Alruzug IM, Alharby E, Samman MA, Ayoub SZ, Maddirevula S, Peake RWA, Alkuraya FS, Wali S, Almontashiri NAM. New paradigms of USP53 disease: normal GGT cholestasis, BRIC, cholangiopathy, and responsiveness to rifampicin. J Hum Genet 2020; 66:151-159. [PMID: 32759993 DOI: 10.1038/s10038-020-0811-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/15/2020] [Accepted: 07/14/2020] [Indexed: 02/07/2023]
Abstract
Biallelic variants in the USP53 gene have recently been reported to segregate with normal gamma glutamyltransferase (GGT) cholestasis. Using whole-exome sequencing (WES), we detected two USP53 homozygous variants (c.951delT; p. Phe317fs and c.1744C>T; p. Arg582*) in five additional cases, including an unpublished cousin of a previously described family with intractable itching and normal GGT cholestasis. Three patients, a child and two adults, presented with recurrent episodes of normal GGT cholestasis, consistent with a diagnosis of benign recurrent intrahepatic cholestasis (BRIC). Cholangiopathic changes, possibly autoimmune in origin, were recognized in some patients. Additional phenotypic details in one patient included an enlarged left kidney, and speech/developmental delay. Notably, two patients exhibited a complete response to rifampicin, and one responded to ursodeoxycholic acid (UDCA). Two adult patients were suspected to have autoimmune liver disease and treated with steroids. This report describes new cases of USP53 disease presenting with normal GGT cholestasis or BRIC in three children and two adults. We also describe the novel finding of a dramatic response to rifampicin. The association of cholangiopathy with normal GGT cholestasis provides a diagnostic challenge and remains poorly understood.
Collapse
Affiliation(s)
- Hamoud Alhebbi
- Department of Pediatrics, Division of Gastroenterology and Hepatology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Abdul Ali Peer-Zada
- Molecular Pathology, Pathology and Clinical Laboratory Medicine Administration, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Abdulrahman A Al-Hussaini
- Pediatric Gastroenterology Division, Children's Specialized Hospital at King Fahad Medical City, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Sara Algubaisi
- Department of Pediatrics, Division of Gastroenterology and Hepatology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Awad Albassami
- Department of Pediatrics, Division of Gastroenterology and Hepatology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Nasser AlMasri
- Department of Adult Gastroenterology and Hepatology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Yasir Alrusayni
- Department of Pathology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Ibrahim M Alruzug
- Department of Adult Gastroenterology and Hepatology, King Saud Medical City, Riyadh, Saudi Arabia
| | - Essa Alharby
- Center for Genetics and Inherited Diseases, Taibah University, Almadinah Almunwarah, Saudi Arabia
| | - Manar A Samman
- Molecular Pathology, Pathology and Clinical Laboratory Medicine Administration, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Syed Zubair Ayoub
- Molecular Pathology, Pathology and Clinical Laboratory Medicine Administration, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Sateesh Maddirevula
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Roy W A Peake
- Department of Laboratory Medicine, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02115, USA
| | - Fowzan S Alkuraya
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia.,Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Sami Wali
- Department of Pediatrics, Division of Gastroenterology and Hepatology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia.
| | - Naif A M Almontashiri
- Center for Genetics and Inherited Diseases, Taibah University, Almadinah Almunwarah, Saudi Arabia. .,Faculty of Applied Medical Sciences, Taibah University, Almadinah Almunwarah, Saudi Arabia.
| |
Collapse
|
23
|
David O, Eskin-Schwartz M, Ling G, Dolgin V, Kristal E, Benkowitz E, Osyntsov L, Gradstein L, Birk OS, Loewenthal N, Yerushalmi B. Pituitary stalk interruption syndrome broadens the clinical spectrum of the TTC26 ciliopathy. Clin Genet 2020; 98:303-307. [PMID: 32617964 DOI: 10.1111/cge.13805] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 06/27/2020] [Accepted: 06/27/2020] [Indexed: 12/11/2022]
Abstract
Ciliopathies are a heterogeneous group of disorders, related to abnormal ciliary function. Severe biliary ciliopathy, caused by bi-allelic mutations in TTC26, has been recently described in the context of a syndrome of polydactyly and severe neonatal cholestasis, with brain, kidney and heart involvement. Pituitary involvement has not been previously reported for patients with this condition. Pituitary stalk interruption syndrome (PSIS) is a congenital anomaly of the pituitary gland, diagnosed by characteristic MRI findings. We now describe four patients with TTC26 ciliopathy due to a homozygous c.695A>G p.Asn232Ser mutation and delineate PSIS as a novel clinical feature of this disorder, highlighting an important role of TTC26 in pituitary development.
Collapse
Affiliation(s)
- Odeya David
- Pediatric Endocrinology Unit, Soroka University Medical Center, Beer-Sheva, Israel.,Saban Pediatric Medical Center for Israel, Soroka University Medical Center, Beer-Sheva, Israel.,Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Marina Eskin-Schwartz
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Genetics Institute at Soroka University Medical Center and the Morris Kahn Laboratory of Human Genetics, National Center for Rare Diseases, at the Faculty of Health Sciences and National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Galina Ling
- Saban Pediatric Medical Center for Israel, Soroka University Medical Center, Beer-Sheva, Israel.,Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Pediatric Gastroenterology Unit, Soroka University Medical Center, Beer-Sheva, Israel
| | - Vadim Dolgin
- Genetics Institute at Soroka University Medical Center and the Morris Kahn Laboratory of Human Genetics, National Center for Rare Diseases, at the Faculty of Health Sciences and National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Eyal Kristal
- Saban Pediatric Medical Center for Israel, Soroka University Medical Center, Beer-Sheva, Israel
| | - Ela Benkowitz
- Radiology Department, Soroka Medical Center, Beer-Sheva, Israel
| | - Lidia Osyntsov
- Institute of Pathology, Soroka Medical Center, Beer-Sheva, Israel
| | - Libe Gradstein
- Genetics Institute at Soroka University Medical Center and the Morris Kahn Laboratory of Human Genetics, National Center for Rare Diseases, at the Faculty of Health Sciences and National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Ophthalmology Clinic, Southern District, Clalit Health Services, Beer-sheva, Israel
| | - Ohad S Birk
- Genetics Institute at Soroka University Medical Center and the Morris Kahn Laboratory of Human Genetics, National Center for Rare Diseases, at the Faculty of Health Sciences and National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Neta Loewenthal
- Pediatric Endocrinology Unit, Soroka University Medical Center, Beer-Sheva, Israel.,Saban Pediatric Medical Center for Israel, Soroka University Medical Center, Beer-Sheva, Israel.,Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Baruch Yerushalmi
- Saban Pediatric Medical Center for Israel, Soroka University Medical Center, Beer-Sheva, Israel.,Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Pediatric Gastroenterology Unit, Soroka University Medical Center, Beer-Sheva, Israel
| |
Collapse
|
24
|
Luan W, Hao CZ, Li JQ, Wei Q, Gong JY, Qiu YL, Lu Y, Shen CH, Xia Q, Xie XB, Zhang MH, Abuduxikuer K, Li ZD, Wang L, Xing QH, Knisely AS, Wang JS. Biallelic loss-of-function ZFYVE19 mutations are associated with congenital hepatic fibrosis, sclerosing cholangiopathy and high-GGT cholestasis. J Med Genet 2020; 58:514-525. [PMID: 32737136 DOI: 10.1136/jmedgenet-2019-106706] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 05/28/2020] [Accepted: 06/20/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND For many children with intrahepatic cholestasis and high-serum gamma-glutamyl transferase (GGT) activity, a genetic aetiology of hepatobiliary disease remains undefined. We sought to identify novel genes mutated in children with idiopathic high-GGT intrahepatic cholestasis, with clinical, histopathological and functional correlations. METHODS We assembled a cohort of 25 children with undiagnosed high-GGT cholestasis and without clinical features of biliary-tract infection or radiological features of choledochal malformation, sclerosing cholangitis or cholelithiasis. Mutations were identified through whole-exome sequencing and targeted Sanger sequencing. We reviewed histopathological findings and assessed phenotypical effects of ZFYVE19 deficiency in cultured cells by immunofluorescence microscopy. RESULTS Nine Han Chinese children harboured biallelic, predictedly complete loss-of-function pathogenic mutations in ZFYVE19 (c.314C>G, p.S105X; c.379C>T, p.Q127X; c.514C>T, p.R172X; c.547C>T, p.R183X; c.226A>G, p.M76V). All had portal hypertension and, at liver biopsy, histopathological features of the ductal plate malformation (DPM)/congenital hepatic fibrosis (CHF). Four children required liver transplantation for recurrent gastrointestinal haemorrhage. DPM/CHF was confirmed at hepatectomy, with sclerosing small-duct cholangitis. Immunostaining for two primary-cilium axonemal proteins found expression that was deficient intraluminally and ectopic within cholangiocyte cytoplasm. ZFYVE19 depletion in cultured cells yielded abnormalities of centriole and axoneme. CONCLUSION Biallelic ZFYVE19 mutations can lead to high-GGT cholestasis and DPM/CHF in vivo. In vitro, they can lead to centriolar and axonemal abnormalities. These observations indicate that mutation in ZFYVE19 results, through as yet undefined mechanisms, in a ciliopathy.
Collapse
Affiliation(s)
- Weisha Luan
- Department of Pediatrics, Jinshan Hospital of Fudan University, Shanghai, China.,The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Chen-Zhi Hao
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Jia-Qi Li
- Department of Pediatrics, Jinshan Hospital of Fudan University, Shanghai, China.,The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Qing Wei
- Laboratory for Reproductive Health, Institute of Biomedicine and Biotechnology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Jing-Yu Gong
- Department of Pediatrics, Jinshan Hospital of Fudan University, Shanghai, China
| | - Yi-Ling Qiu
- Department of Pediatrics, Jinshan Hospital of Fudan University, Shanghai, China.,The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Yi Lu
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Cong-Huan Shen
- Department of Surgery, Huashan Hospital Affiliated to Fudan University, Shanghai, China
| | - Qiang Xia
- Department of Liver Surgery and Liver Transplantation Center, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Xin-Bao Xie
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Mei-Hong Zhang
- Department of Pediatrics, Jinshan Hospital of Fudan University, Shanghai, China
| | - Kuerbanjiang Abuduxikuer
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Zhong-Die Li
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Li Wang
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Qing-He Xing
- Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - A S Knisely
- Institut für Pathologie, Medizinische Universität Graz, Graz, Austria
| | - Jian-She Wang
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| |
Collapse
|
25
|
Shamseldin HE, Shaheen R, Ewida N, Bubshait DK, Alkuraya H, Almardawi E, Howaidi A, Sabr Y, Abdalla EM, Alfaifi AY, Alghamdi JM, Alsagheir A, Alfares A, Morsy H, Hussein MH, Al-Muhaizea MA, Shagrani M, Al Sabban E, Salih MA, Meriki N, Khan R, Almugbel M, Qari A, Tulba M, Mahnashi M, Alhazmi K, Alsalamah AK, Nowilaty SR, Alhashem A, Hashem M, Abdulwahab F, Ibrahim N, Alshidi T, AlObeid E, Alenazi MM, Alzaidan H, Rahbeeni Z, Al-Owain M, Sogaty S, Seidahmed MZ, Alkuraya FS. The morbid genome of ciliopathies: an update. Genet Med 2020; 22:1051-1060. [PMID: 32055034 DOI: 10.1038/s41436-020-0761-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Ciliopathies are highly heterogeneous clinical disorders of the primary cilium. We aim to characterize a large cohort of ciliopathies phenotypically and molecularly. METHODS Detailed phenotypic and genomic analysis of patients with ciliopathies, and functional characterization of novel candidate genes. RESULTS In this study, we describe 125 families with ciliopathies and show that deleterious variants in previously reported genes, including cryptic splicing variants, account for 87% of cases. Additionally, we further support a number of previously reported candidate genes (BBIP1, MAPKBP1, PDE6D, and WDPCP), and propose nine novel candidate genes (CCDC67, CCDC96, CCDC172, CEP295, FAM166B, LRRC34, TMEM17, TTC6, and TTC23), three of which (LRRC34, TTC6, and TTC23) are supported by functional assays that we performed on available patient-derived fibroblasts. From a phenotypic perspective, we expand the phenomenon of allelism that characterizes ciliopathies by describing novel associations including WDR19-related Stargardt disease and SCLT1- and CEP164-related Bardet-Biedl syndrome. CONCLUSION In this cohort of phenotypically and molecularly characterized ciliopathies, we draw important lessons that inform the clinical management and the diagnostics of this class of disorders as well as their basic biology.
Collapse
Affiliation(s)
- Hanan E Shamseldin
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Ranad Shaheen
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Nour Ewida
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Dalal K Bubshait
- Department of Pediatrics, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Hisham Alkuraya
- Department of Ophthalmology, Specialized Medical Center Hospital, Riyadh, Saudi Arabia
| | - Elham Almardawi
- Department of Obstetrics and Gynecology, Security Forces Hospital, Riyadh, Saudi Arabia
| | - Ali Howaidi
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Yasser Sabr
- Deparment of Obstetrics and Gynecology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Ebtesam M Abdalla
- Human Genetics Department, Medical Research Institute, Alexandria University, Alexandria, Egypt
| | - Abdullah Y Alfaifi
- Department of Pediatrics, Security Forces Hospital, Riyadh, Saudi Arabia
| | | | - Afaf Alsagheir
- Endocrinology Section, Department of Pediatrics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Ahmed Alfares
- Department of Pediatrics, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Heba Morsy
- Human Genetics Department, Medical Research Institute, Alexandria University, Alexandria, Egypt
| | - Maged H Hussein
- Nephrology Section, Department of Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mohammad A Al-Muhaizea
- Department of Neuroscience, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mohammad Shagrani
- Organ Transplant Center, King Faisal Specialist Hospital and Research Center, and College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Essam Al Sabban
- Nephrology Section, Department of Pediatrics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mustafa A Salih
- Division of Pediatric Neurology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Neama Meriki
- Department of Obstetrics and Gynecology, Security Forces Hospital, Riyadh, Saudi Arabia
| | - Rubina Khan
- Depatment of Obstetrics and Gynecology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Maisoon Almugbel
- Depatment of Obstetrics and Gynecology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Alya Qari
- Department of Medical Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Maha Tulba
- Depatment of Obstetrics and Gynecology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mohammed Mahnashi
- Divison of Genetics, Department of General Pediatrics, King Fahad Central Hospital, Jazan, Saudi Arabia
| | - Khalid Alhazmi
- Divison of Genetics, Department of General Pediatrics, King Fahad Central Hospital, Jazan, Saudi Arabia
| | - Abrar K Alsalamah
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Sawsan R Nowilaty
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Amal Alhashem
- Department of Pediatrics, Prince Sultan Military Medical City, Riyadh, Saudi Arabia.,Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Mais Hashem
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Firdous Abdulwahab
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Niema Ibrahim
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Tarfa Alshidi
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Eman AlObeid
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mona M Alenazi
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Hamad Alzaidan
- Department of Medical Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Zuhair Rahbeeni
- Department of Medical Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mohammed Al-Owain
- Department of Medical Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Sameera Sogaty
- Department of Pediatrics, King Fahad General Hospital, Jeddah, Saudi Arabia
| | | | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. .,Department of Pediatrics, Prince Sultan Military Medical City, Riyadh, Saudi Arabia. .,Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia.
| |
Collapse
|