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Huang Y, Ma M, Mao X, Pehlivan D, Kanca O, Un-Candan F, Shu L, Akay G, Mitani T, Lu S, Candan S, Wang H, Xiao B, Lupski JR, Bellen HJ. Novel dominant and recessive variants in human ROBO1 cause distinct neurodevelopmental defects through different mechanisms. Hum Mol Genet 2022; 31:2751-2765. [PMID: 35348658 PMCID: PMC9402236 DOI: 10.1093/hmg/ddac070] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/17/2022] [Accepted: 03/20/2022] [Indexed: 07/27/2023] Open
Abstract
The Roundabout (Robo) receptors, located on growth cones of neurons, induce axon repulsion in response to the extracellular ligand Slit. The Robo family of proteins controls midline crossing of commissural neurons during development in flies. Mono- and bi-allelic variants in human ROBO1 (HGNC: 10249) have been associated with incomplete penetrance and variable expressivity for a breath of phenotypes, including neurodevelopmental defects such as strabismus, pituitary defects, intellectual impairment, as well as defects in heart and kidney. Here, we report two novel ROBO1 variants associated with very distinct phenotypes. A homozygous missense p.S1522L variant in three affected siblings with nystagmus; and a monoallelic de novo p.D422G variant in a proband who presented with early-onset epileptic encephalopathy. We modeled these variants in Drosophila and first generated a null allele by inserting a CRIMIC T2A-GAL4 in an intron. Flies that lack robo1 exhibit reduced viability but have very severe midline crossing defects in the central nervous system. The fly wild-type cDNA driven by T2A-Gal4 partially rescues both defects. Overexpression of the human reference ROBO1 with T2A-GAL4 is toxic and reduces viability, whereas the recessive p.S1522L variant is less toxic, suggesting that it is a partial loss-of-function allele. In contrast, the dominant variant in fly robo1 (p.D413G) affects protein localization, impairs axonal guidance activity and induces mild phototransduction defects, suggesting that it is a neomorphic allele. In summary, our studies expand the phenotypic spectrum associated with ROBO1 variant alleles.
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Affiliation(s)
- Yan Huang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mengqi Ma
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xiao Mao
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Davut Pehlivan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Division of Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children’s Hospital, Houston, TX 77030, USA
| | - Oguz Kanca
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Feride Un-Candan
- Department of Neuroloy, Balikesir Ataturk Public Hospital, Balikesir 10100, Turkey
| | - Li Shu
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Gulsen Akay
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sukru Candan
- Department of Medical Genetics, Balikesir Ataturk Public Hospital, Balikesir 10100, Turkey
| | - Hua Wang
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Bo Xiao
- Neurology Department, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children’s Hospital, Houston, TX 77030, USA
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
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Münch J, Engesser M, Schönauer R, Hamm JA, Hartig C, Hantmann E, Akay G, Pehlivan D, Mitani T, Coban Akdemir Z, Tüysüz B, Shirakawa T, Dateki S, Claus LR, van Eerde AM, Smol T, Devisme L, Franquet H, Attié-Bitach T, Wagner T, Bergmann C, Höhn AK, Shril S, Pollack A, Wenger T, Scott AA, Paolucci S, Buchan J, Gabriel GC, Posey JE, Lupski JR, Petit F, McCarthy AA, Pazour GJ, Lo CW, Popp B, Halbritter J. Biallelic pathogenic variants in roundabout guidance receptor 1 associate with syndromic congenital anomalies of the kidney and urinary tract. Kidney Int 2022; 101:1039-1053. [PMID: 35227688 PMCID: PMC10010616 DOI: 10.1016/j.kint.2022.01.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 11/30/2021] [Accepted: 01/11/2022] [Indexed: 11/16/2022]
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUT) represent the most common cause of chronic kidney failure in children. Despite growing knowledge of the genetic causes of CAKUT, the majority of cases remain etiologically unsolved. Genetic alterations in roundabout guidance receptor 1 (ROBO1) have been associated with neuronal and cardiac developmental defects in living individuals. Although Slit-Robo signaling is pivotal for kidney development, diagnostic ROBO1 variants have not been reported in viable CAKUT to date. By next-generation-sequencing methods, we identified six unrelated individuals and two non-viable fetuses with biallelic truncating or combined missense and truncating variants in ROBO1. Kidney and genitourinary manifestation included unilateral or bilateral kidney agenesis, vesicoureteral junction obstruction, vesicoureteral reflux, posterior urethral valve, genital malformation, and increased kidney echogenicity. Further clinical characteristics were remarkably heterogeneous, including neurodevelopmental defects, intellectual impairment, cerebral malformations, eye anomalies, and cardiac defects. By in silico analysis, we determined the functional significance of identified missense variants and observed absence of kidney ROBO1 expression in both human and murine mutant tissues. While its expression in multiple tissues may explain heterogeneous organ involvement, variability of the kidney disease suggests gene dosage effects due to a combination of null alleles with mild hypomorphic alleles. Thus, comprehensive genetic analysis in CAKUT should include ROBO1 as a new cause of recessively inherited disease. Hence, in patients with already established ROBO1-associated cardiac or neuronal disorders, screening for kidney involvement is indicated.
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Affiliation(s)
- Johannes Münch
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Marie Engesser
- Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Ria Schönauer
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - J Austin Hamm
- East Tennessee Children's Hospital, Genetic Center, Knoxville, Tennessee, USA
| | - Christin Hartig
- Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Elena Hantmann
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Gulsen Akay
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Department of Pediatrics, University of Utah, Salt Lake, Utah, USA
| | - Davut Pehlivan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Division of Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA; Texas Children's Hospital, Houston, Texas, USA
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Zeynep Coban Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Department of Epidemiology, Human Genetics, and Environmental Sciences, Human Genetics Center, School of Public Health, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Beyhan Tüysüz
- Department of Pediatric Genetics, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey
| | | | - Sumito Dateki
- Department of Pediatrics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Laura R Claus
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | | | - Thomas Smol
- Centre Hospitalier Universitaire de Lille, Institut de Génétique Médicale, Lille, France
| | - Louise Devisme
- Centre Hospitalier Universitaire de Lille, Institut de Pathologie, Lille, France
| | - Hélène Franquet
- Centre Hospitalier Universitaire de Lille, Institut de Pathologie, Lille, France
| | - Tania Attié-Bitach
- Laboratoire de biologie médicale multisites SeqOIA, Paris, France; Service de Médecine Génomique des Maladies Rares, APHP.Centre, Université de Paris, Paris, France
| | - Timo Wagner
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany
| | - Carsten Bergmann
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany; Department of Medicine, Nephrology, University Hospital Freiburg, Freiburg, Germany
| | - Anne Kathrin Höhn
- Division of Pathology, University of Leipzig Medical Center, Leipzig, Germany
| | - Shirlee Shril
- Division of Nephrology, Boston Children's Hospital, Boston, USA
| | - Ari Pollack
- Division of Genetic Medicine, University of Washington, Seattle, Washington, USA
| | - Tara Wenger
- Division of Genetic Medicine, University of Washington, Seattle, Washington, USA
| | - Abbey A Scott
- Division of Genetic Medicine, Seattle Children's Hospital, Seattle, Washington, USA
| | - Sarah Paolucci
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - Jillian Buchan
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - George C Gabriel
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Texas Children's Hospital, Houston, Texas, USA; Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Florence Petit
- Centre Hospitalier Universitaire de Lille, Clinique de Génétique Guy Fontaine, Lille, France
| | | | - Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Medical School, Biotech II, Worcester, USA
| | - Cecilia W Lo
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
| | - Bernt Popp
- Institute for Human Genetics, University of Leipzig Medical Center, Leipzig, Germany.
| | - Jan Halbritter
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany.
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Darlow JM, Dobson MG, Green AJ, Puri P, Barton DE. Investigation of DNA variants specific to ROBO2 Isoform 'a' in Irish vesicoureteric reflux patients reveals marked CpG island variation. Sci Rep 2020; 10:2265. [PMID: 32041992 PMCID: PMC7010700 DOI: 10.1038/s41598-020-58818-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 11/29/2019] [Indexed: 11/09/2022] Open
Abstract
ROBO2 gene disruption causes vesicoureteric reflux (VUR) amongst other congenital anomalies. Several VUR patient cohorts have been screened for variants in the ubiquitously expressed transcript, ROBO2b, but, apart from low levels in a few adult tissues, ROBO2a expression is confined to the embryo, and might be more relevant to VUR, a developmental disorder. ROBO2a has an alternative promoter and two alternative exons which replace the first exon of ROBO2b. We screened probands from 251 Irish VUR families for DNA variants in these. The CpG island of ROBO2a, which includes the non-coding first exon, was found to contain a run of six variants abolishing/creating CpG dinucleotides, including a novel variant, present in the VUR cases in one family, that was not present in 592 healthy Irish controls. In three of these positions, the CpG was created by the non-reference allele, and the reference allele was not the nucleotide that would result from spontaneous deamination of methylcytosine to thymine, suggesting that there might have been selection for variability in number of CpGs in this island. This is in marked contrast to the CpG island at the start of ROBO2b, which only contained a single variant that abolishes a CpG.
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Affiliation(s)
- John M Darlow
- Department of Clinical Genetics, Dublin, Ireland. .,National Children's Research Centre, Dublin, Ireland.
| | - Mark G Dobson
- Department of Clinical Genetics, Dublin, Ireland.,National Children's Research Centre, Dublin, Ireland
| | - Andrew J Green
- Department of Clinical Genetics, Dublin, Ireland.,School of Medicine and Medical Science, University College Dublin - all at Our Lady's Children's Hospital, Crumlin, (now renamed 'Children's Health Ireland at Crumlin'), Crumlin, Dublin, D12 N512, Ireland
| | - Prem Puri
- National Children's Research Centre, Dublin, Ireland.,School of Medicine and Medical Science, University College Dublin - all at Our Lady's Children's Hospital, Crumlin, (now renamed 'Children's Health Ireland at Crumlin'), Crumlin, Dublin, D12 N512, Ireland.,Beacon Hospital, Beacon Court, Sandyford, Dublin, D18 AK68, Ireland
| | - David E Barton
- Department of Clinical Genetics, Dublin, Ireland.,School of Medicine and Medical Science, University College Dublin - all at Our Lady's Children's Hospital, Crumlin, (now renamed 'Children's Health Ireland at Crumlin'), Crumlin, Dublin, D12 N512, Ireland
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Yu M, Tan L, Li Y, Chen J, Zhai Y, Rao J, Fang X, Wu X, Xu H, Shen Q. Intrauterine low-protein diet aggravates developmental abnormalities of the urinary system via the Akt/Creb3 pathway in Robo2 mutant mice. Am J Physiol Renal Physiol 2019; 318:F43-F52. [PMID: 31630547 DOI: 10.1152/ajprenal.00405.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The offspring of Robo2 mutant mice usually present with variable phenotypes of congenital anomalies of the kidney and urinary tract (CAKUT). An intrauterine low-protein diet can also cause CAKUT in offspring, dominated by the duplicated collecting system phenotype. A single genetic or environment factor can only partially explain the pathogenesis of CAKUT. The present study aimed to establish an intrauterine low-protein diet roundabout 2 (Robo2) mutant mouse model and found that the intrauterine low-protein diet led to significantly increased CAKUT phenotypes in Robo2PB/+ mice offspring, dominant by a duplicated collecting system. At the same time, more ectopic and lower located ureteric buds (UBs) were observed in the intrauterine low-protein diet-fed Robo2 mutant mouse model, and the number of UB branches was reduced in the serum-free culture. During UB protrusion, intrauterine low-protein diet reduced the expression of Slit2/Robo2 in Robo2 mutant mice and affected the expression of glial cell-derived neurotrophic factor/Ret, which is a key molecule for metanephric development, with increasing phospho-Akt and phospho-cAMP responsive element-binding protein 3 activity and a reduction of apoptotic cells in embryonic day 11.5 UB tissues. The mechanism by which an intrauterine low-protein diet aggravates CAKUT in Robo2 mutant mice may be related to the disruption of Akt/cAMP responsive element-binding protein 3 signaling and a reduction in apoptosis in UB tissue.
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Affiliation(s)
- Minghui Yu
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Lihong Tan
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Yaxin Li
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Jing Chen
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Yihui Zhai
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Jia Rao
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Xiaoyan Fang
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Xiaohui Wu
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China.,State Key Laboratory of Genetic Engineering and National Center for International Research of Development and Disease, Institute of Developmental Biology and Molecular Medicine, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Hong Xu
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
| | - Qian Shen
- Department of Nephrology, Children's Hospital of Fudan University, Shanghai Kidney Development and Pediatric Kidney Disease Research Center, Shanghai, China
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Li Q, Cui S, Ma Q, Liu Y, Yu H, Geng G, Agborbesong E, Ren C, Wei K, Zhang Y, Yang J, Bai X, Cai G, Xie Y, Li X, Chen X. Disruption of Robo2-Baiap2 integrated signaling drives cystic disease. JCI Insight 2019; 4:127602. [PMID: 31534052 DOI: 10.1172/jci.insight.127602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 08/21/2019] [Indexed: 11/17/2022] Open
Abstract
Hereditary renal cystic diseases are characterized by defects in primary cilia of renal tubular epithelial cells and abnormality of tubular epithelium, which ultimately result in the development of renal cysts. However, the mechanism leading from abnormality of the tubular epithelium to cystogenesis is not well understood. In this report, we demonstrate a critical role for Robo2 in regulating epithelial development, including ciliogenesis, polarization, and differentiation. We found that Robo2 deficiency results in cystic kidneys, and the cyst cells showed defective cilia and polarity defects in tubular epithelium. The cyst cells, less than terminally differentiated, continue to proliferate. We further established that Robo2 works with p53 as well as polarity and ciliary proteins (Par3, PKCς, ZO-2, and Claudin-2) to regulate these processes. Robo2 binds to Baiap2 (also known as IRSp53) through the IRSp53/MIM homology domain in renal epithelial cells. This binding allows Robo2 to phosphorylate MDM2 at Ser166 via Baiap2 and maintain p53 homeostasis. Disruption of the Robo2-Baiap2 complex causes MDM2 to be subjected to dephosphorylation, leading to a high level of active p53, and initiated p53-mediated cellular senescence via p21 and decreased the expression of ZO-1, ZO-2, PKCς, Par3, and Claudin-2 proteins, resulting in defects in epithelial development, including ciliogenesis, polarization, and differentiation. Importantly, double knockout of Robo2 and p53 rescued all the epithelial defects in kidneys compared with those in Robo2-knockout kidneys. Taken together, the present results demonstrate that Robo2 deficiency causes renal cystic disease, which is largely dependent on defective Robo2-Baiap2 integrated signaling in kidneys.
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Affiliation(s)
- Qinggang Li
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Shaoyuan Cui
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Qian Ma
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Ying Liu
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Hongyu Yu
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - GuangRui Geng
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Ewud Agborbesong
- Department of Internal Medicine, Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Chongyu Ren
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Kai Wei
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Yingjie Zhang
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Jurong Yang
- Department of Urology, Third Affiliated Hospital of Chongqing Medical University (General Hospital), Chongqing, China
| | - Xueyuan Bai
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Guangyan Cai
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Yuansheng Xie
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| | - Xiaogang Li
- Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Xiangmei Chen
- Department of Nephrology, Chinese PLA General Hospital, Medical School of Chinese PLA, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
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6
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Woolf AS, Lopes FM, Ranjzad P, Roberts NA. Congenital Disorders of the Human Urinary Tract: Recent Insights From Genetic and Molecular Studies. Front Pediatr 2019; 7:136. [PMID: 31032239 PMCID: PMC6470263 DOI: 10.3389/fped.2019.00136] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 03/22/2019] [Indexed: 12/13/2022] Open
Abstract
The urinary tract comprises the renal pelvis, the ureter, the urinary bladder, and the urethra. The tract acts as a functional unit, first propelling urine from the kidney to the bladder, then storing it at low pressure inside the bladder which intermittently and completely voids urine through the urethra. Congenital diseases of these structures can lead to a range of diseases sometimes associated with fetal losses or kidney failure in childhood and later in life. In some of these disorders, parts of the urinary tract are severely malformed. In other cases, the organs appear grossly intact yet they have functional deficits that compromise health. Human studies are beginning to indicate monogenic causes for some of these diseases. Here, the implicated genes can encode smooth muscle, neural or urothelial molecules, or transcription factors that regulate their expression. Furthermore, certain animal models are informative about how such molecules control the development and functional differentiation of the urinary tract. In future, novel therapies, including those based on gene transfer and stem cell technologies, may be used to treat these diseases to complement conventional pharmacological and surgical clinical therapies.
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Affiliation(s)
- Adrian S Woolf
- Division of Cell Matrix Biology and Regenerative Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom.,Royal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Filipa M Lopes
- Division of Cell Matrix Biology and Regenerative Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Parisa Ranjzad
- Division of Cell Matrix Biology and Regenerative Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Neil A Roberts
- Division of Cell Matrix Biology and Regenerative Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
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7
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Liu J, Sun L, Shen Q, Wu X, Xu H. New congenital anomalies of the kidney and urinary tract and outcomes in Robo2 mutant mice with the inserted piggyBac transposon. BMC Nephrol 2016; 17:98. [PMID: 27460642 PMCID: PMC4962383 DOI: 10.1186/s12882-016-0308-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 07/19/2016] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Disruption of ROBO2 in humans causes vesicoureteral reflux (VUR)/congenital anomalies of the kidney and urinary tract (CAKUT). PiggyBac (PB) is a DNA transposon, and its insertion often reduces-but does not eliminate-gene expression. The Robo2 insertion mutant exhibited non-dilating VUR, ureteropelvic junction obstruction (UPJO) not found in reported models. We studied the incidence and outcomes of VUR/CAKUT in this mutant and explored the relationship between Robo2 gene expression and the occurrence and severity of VUR/CAKUT. METHODS The urinary systems of newborn mutants were evaluated via Vevo 770 micro-ultrasound. Some of the normal animals-and all of the abnormal animals-were followed to adulthood and tested for VUR. Urinary obstruction experiments were performed on mice with hydronephrosis. The histology of the kidney and ureter was examined by light microscopy and transmission electron microscopy. Robo2 (PB/PB) mice were crossed with Hoxb7/myr-Venus mice to visualize the location of the ureters relative to the bladder. RESULTS In Robo2 (PB/PB) mice, PB insertion led to an approximately 50 % decrease in Robo2 gene expression. The most common (27.07 %, 62/229) abnormality was non-dilating VUR, and no statistically significant differences were found between age groups. Approximately 6.97 % displayed ultrasound-detectable CAKUT, and these mice survived to adulthood without improvement. No severe CAKUT were found in Robo2 (PB/+) mice. The refluxing ureters showed disorganized smooth muscle fibers, reduced muscle cell populations, intercellular edema and intracytoplasmic vacuoles in smooth muscle cells. Both UPJ and UVJ muscle defects were noted in Robo2 (PB/PB) mice. CONCLUSIONS Robo2 (PB/PB) mice is the first Robo2-deficient mouse model to survive to adulthood while displaying non-dilating VUR, UPJO, and multiple ureters with blind endings. The genetic background of these mutants may influence the penetrance and severity of the CAKUT phenotypes. VUR and other CAKUT found in this mutant had little chance of spontaneous resolution, and this requires careful follow-up. We reported for the first time that the non-dilated refluxing ureters showed disorganized smooth muscle fibers and altered smooth muscle cell structure, more accurately mimicking the characteristics of human cases. Future studies are required to test the role of Robo2 in the ureteric smooth muscle.
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Affiliation(s)
- Jialu Liu
- Department of Nephrology and Rheumatism, Children's Hospital of Fudan University, 399 WanYuan Road, Shanghai, 201102, China
| | - Li Sun
- Department of Nephrology and Rheumatism, Children's Hospital of Fudan University, 399 WanYuan Road, Shanghai, 201102, China
| | - Qian Shen
- Department of Nephrology and Rheumatism, Children's Hospital of Fudan University, 399 WanYuan Road, Shanghai, 201102, China
| | - Xiaohui Wu
- State Key Laboratory of Genetic Engineering and National Center for International Research of Development and Disease, Institute of Developmental Biology and Molecular Medicine, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200433, China
| | - Hong Xu
- Department of Nephrology and Rheumatism, Children's Hospital of Fudan University, 399 WanYuan Road, Shanghai, 201102, China.
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ROBO2 gene variants in children with primary nonsyndromic vesicoureteral reflux with or without renal hypoplasia/dysplasia. Pediatr Res 2016; 80:72-6. [PMID: 27002985 DOI: 10.1038/pr.2016.51] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 01/08/2016] [Indexed: 01/01/2023]
Abstract
BACKGROUND Primary nonsyndromic vesicoureteral reflux (VUR) and VUR with renal hypoplasia/dysplasia (VUR-RHD) are common congenital anomalies of the kidney and urinary tract (CAKUT). Sequence variations of the ROBO2 gene were investigated in children with nonsyndromic VUR or VUR-RHD. METHODS Single-strand conformation polymorphism (SSCP) electrophoresis or multiple restriction fragment SSCP (MRF-SSCP), followed occasionally by direct sequencing, was used to screen 103 patients and 200 controls for nucleotide changes. Gene polymorphisms and transposable elements were investigated using bioinformatics. RESULTS Two single-nucleotide polymorphisms were detected: IVS1-53 and IVS5-31. The frequency of A allele of IVS1-53G>A did not differ significantly between patients and controls. IVS1-53 does not affect mRNA splicing according to in silico analysis. IVS5-31A>G substitution was found in one patient, reported here for the first time in VUR. In silico results demonstrated alteration in two serine/arginine-rich (SR) protein-binding sites and two additional acceptor sites. The ROBO2 gene sequence was found to contain 25.9% transposable elements. CONCLUSION ROBO2 variants were not found to be associated with nonsyndromic VUR or VUR-RHD, providing further evidence for genetic heterogeneity. The role of transposable elements in ROBO2 gene expression in CAKUT needs further investigation since they are generally considered to be mutagens.
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Nino F, Ilari M, Noviello C, Santoro L, Rätsch IM, Martino A, Cobellis G. Genetics of Vesicoureteral Reflux. Curr Genomics 2016; 17:70-9. [PMID: 27013925 PMCID: PMC4780477 DOI: 10.2174/1389202916666151014223507] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 06/29/2015] [Accepted: 07/05/2015] [Indexed: 12/13/2022] Open
Abstract
Vesicoureteral reflux (VUR) is the retrograde passage of urine from the bladder to the upper urinary tract. It is the most common congenital urological anomaly affecting 1-2% of children and 30-40% of patients with urinary tract infections. VUR is a major risk factor for pyelonephritic scarring and chronic renal failure in children. It is the result of a shortened intravesical ureter with an enlarged or malpositioned ureteric orifice. An ectopic embryonal ureteric budding development is implicated in the pathogenesis of VUR, which is a complex genetic developmental disorder. Many genes are involved in the ureteric budding formation and subsequently in the urinary tract and kidney development. Previous studies demonstrate an heterogeneous genetic pattern of VUR. In fact no single major locus or gene for primary VUR has been identified. It is likely that different forms of VUR with different genetic determinantes are present. Moreover genetic studies of syndromes with associated VUR have revealed several possible candidate genes involved in the pathogenesis of VUR and related urinary tract malformations. Mutations in genes essential for urinary tract morphogenesis are linked to numerous congenital syndromes, and in most of those VUR is a feature. The Authors provide an overview of the developmental processes leading to the VUR. The different genes and signaling pathways controlling the embryonal urinary tract development are analyzed. A better understanding of VUR genetic bases could improve the management of this condition in children.
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Affiliation(s)
- F Nino
- Pediatric Surgery Unit - Salesi Children s Hospital - UniversitPolitecnica delle Marche - Ancona,Italy
| | - M Ilari
- Pediatric Surgery Unit - Salesi Children s Hospital - UniversitPolitecnica delle Marche - Ancona,Italy
| | - C Noviello
- Pediatric Surgery Unit - Salesi Children s Hospital - UniversitPolitecnica delle Marche - Ancona,Italy
| | - L Santoro
- Clinics of Pediatrics - Pediatric Nephrology Unit - Salesi Children s Hospital - Universit Politecnica delle Marche - Ancona, Italy
| | - I M Rätsch
- Clinics of Pediatrics - Pediatric Nephrology Unit - Salesi Children s Hospital - Universit Politecnica delle Marche - Ancona, Italy
| | - A Martino
- Pediatric Surgery Unit - Salesi Children s Hospital - UniversitPolitecnica delle Marche - Ancona,Italy
| | - G Cobellis
- Pediatric Surgery Unit - Salesi Children s Hospital - UniversitPolitecnica delle Marche - Ancona,Italy
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10
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Hwang DY, Kohl S, Fan X, Vivante A, Chan S, Dworschak GC, Schulz J, van Eerde AM, Hilger AC, Gee HY, Pennimpede T, Herrmann BG, van de Hoek G, Renkema KY, Schell C, Huber TB, Reutter HM, Soliman NA, Stajic N, Bogdanovic R, Kehinde EO, Lifton RP, Tasic V, Lu W, Hildebrandt F. Mutations of the SLIT2-ROBO2 pathway genes SLIT2 and SRGAP1 confer risk for congenital anomalies of the kidney and urinary tract. Hum Genet 2015; 134:905-16. [PMID: 26026792 PMCID: PMC4497857 DOI: 10.1007/s00439-015-1570-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 05/18/2015] [Indexed: 12/26/2022]
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUT) account for 40-50% of chronic kidney disease that manifests in the first two decades of life. Thus far, 31 monogenic causes of isolated CAKUT have been described, explaining ~12% of cases. To identify additional CAKUT-causing genes, we performed whole-exome sequencing followed by a genetic burden analysis in 26 genetically unsolved families with CAKUT. We identified two heterozygous mutations in SRGAP1 in 2 unrelated families. SRGAP1 is a small GTPase-activating protein in the SLIT2-ROBO2 signaling pathway, which is essential for development of the metanephric kidney. We then examined the pathway-derived candidate gene SLIT2 for mutations in cohort of 749 individuals with CAKUT and we identified 3 unrelated individuals with heterozygous mutations. The clinical phenotypes of individuals with mutations in SLIT2 or SRGAP1 were cystic dysplastic kidneys, unilateral renal agenesis, and duplicated collecting system. We show that SRGAP1 is expressed in early mouse nephrogenic mesenchyme and that it is coexpressed with ROBO2 in SIX2-positive nephron progenitor cells of the cap mesenchyme in developing rat kidney. We demonstrate that the newly identified mutations in SRGAP1 lead to an augmented inhibition of RAC1 in cultured human embryonic kidney cells and that the SLIT2 mutations compromise the ability of the SLIT2 ligand to inhibit cell migration. Thus, we report on two novel candidate genes for causing monogenic isolated CAKUT in humans.
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Affiliation(s)
- Daw-Yang Hwang
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Division of Nephrology, Department of Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Stefan Kohl
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Xueping Fan
- Renal Section, Department of Medicine, Boston University Medical Center, Boston, MA, USA
| | - Asaf Vivante
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Stefanie Chan
- Renal Section, Department of Medicine, Boston University Medical Center, Boston, MA, USA
| | - Gabriel C Dworschak
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Institute of Human Genetics, University of Bonn, Bonn, Germany
| | - Julian Schulz
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Albertien M van Eerde
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Alina C Hilger
- Institute of Human Genetics, University of Bonn, Bonn, Germany
| | - Heon Yung Gee
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Tracie Pennimpede
- Max Planck Institute for Molecular Genetics, Developmental Genetics Department, Berlin, Germany
| | - Bernhard G Herrmann
- Max Planck Institute for Molecular Genetics, Developmental Genetics Department, Berlin, Germany
| | - Glenn van de Hoek
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Kirsten Y Renkema
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Christoph Schell
- Renal Division, University Hospital Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine, Albert-Ludwigs-University, Freiburg, Germany
- Faculty of Biology, Albert-Ludwigs-University, Freiburg, Germany
| | - Tobias B Huber
- Renal Division, University Hospital Freiburg, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, Albert-Ludwigs-University Freiburg, Germany
| | - Heiko M Reutter
- Institute of Human Genetics, University of Bonn, Bonn, Germany
- Department of Neonatology, Children’s Hospital, University of Bonn, Bonn, Germany
| | - Neveen A Soliman
- Department of Pediatrics, Kasr Al Ainy School of Medicine, Cairo University, Cairo, Egypt
- Egyptian Group for Orphan Renal Diseases (EGORD), Cairo, Egypt
| | - Natasa Stajic
- Medical Faculty, University of Belgrade, Belgrade, Serbia
- Institute of Mother and Child Healthcare of Serbia, Belgrade, Serbia
| | - Radovan Bogdanovic
- Medical Faculty, University of Belgrade, Belgrade, Serbia
- Institute of Mother and Child Healthcare of Serbia, Belgrade, Serbia
| | | | - Richard P Lifton
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- Yale Center for Mendelian Genomics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Velibor Tasic
- Department of Pediatric Nephrology, University Children’s Hospital, Skopje, Macedonia
| | - Weining Lu
- Renal Section, Department of Medicine, Boston University Medical Center, Boston, MA, USA
| | - Friedhelm Hildebrandt
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
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11
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Vesicoureteric reflux and reflux nephropathy: from mouse models to childhood disease. Pediatr Nephrol 2014; 29:757-66. [PMID: 24500705 DOI: 10.1007/s00467-014-2761-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 12/30/2013] [Accepted: 01/08/2014] [Indexed: 12/16/2022]
Abstract
Vesicoureteric reflux (VUR) is a common congenital urinary tract defect that predisposes children to recurrent kidney infections. Kidney infections can result in renal scarring or reflux nephropathy defined by the presence of chronic tubulo-interstitial inflammation and fibrosis that is a frequent cause of end-stage renal failure. The discovery of mouse models with VUR and with reflux nephropathy has provided new opportunities to understand the pathogenesis of these conditions and may provide insight on the genes and the associated phenotypes that need to be examined in human studies.
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12
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Darlow JM, Dobson MG, Darlay R, Molony CM, Hunziker M, Green AJ, Cordell HJ, Puri P, Barton DE. A new genome scan for primary nonsyndromic vesicoureteric reflux emphasizes high genetic heterogeneity and shows linkage and association with various genes already implicated in urinary tract development. Mol Genet Genomic Med 2013; 2:7-29. [PMID: 24498626 PMCID: PMC3907909 DOI: 10.1002/mgg3.22] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 05/21/2013] [Indexed: 12/18/2022] Open
Abstract
Primary vesicoureteric reflux (VUR), the retrograde flow of urine from the bladder toward the kidneys, results from a developmental anomaly of the vesicoureteric valve mechanism, and is often associated with other urinary tract anomalies. It is the most common urological problem in children, with an estimated prevalence of 1–2%, and is a major cause of hypertension in childhood and of renal failure in childhood or adult life. We present the results of a genetic linkage and association scan using 900,000 markers. Our linkage results show a large number of suggestive linkage peaks, with different results in two groups of families, suggesting that VUR is even more genetically heterogeneous than previously imagined. The only marker achieving P < 0.02 for linkage in both groups of families is 270 kb from EMX2. In three sibships, we found recessive linkage to KHDRBS3, previously reported in a Somali family. In another family we discovered sex-reversal associated with VUR, implicating PRKX, for which there was weak support for dominant linkage in the overall data set. Several other candidate genes are suggested by our linkage or association results, and four of our linkage peaks are within copy-number variants recently found to be associated with renal hypodysplasia. Undoubtedly there are many genes related to VUR. Our study gives support to some loci suggested by earlier studies as well as suggesting new ones, and provides numerous indications for further investigations.
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Affiliation(s)
- J M Darlow
- National Centre for Medical Genetics, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland ; National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland
| | - M G Dobson
- National Centre for Medical Genetics, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland ; National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland
| | - R Darlay
- Institute of Genetic Medicine, Newcastle University Newcastle upon Tyne, United Kingdom
| | - C M Molony
- Merck & Co. Inc 1 Merck Drive, Whitehouse Station, New Jersey, 08889
| | - M Hunziker
- National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland ; National Children's Hospital Tallaght, Dublin, 24, Ireland
| | - A J Green
- National Centre for Medical Genetics, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland ; University College Dublin UCD School of Medicine and Medical Sciences, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland
| | - H J Cordell
- Institute of Genetic Medicine, Newcastle University Newcastle upon Tyne, United Kingdom
| | - P Puri
- National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland ; National Children's Hospital Tallaght, Dublin, 24, Ireland
| | - D E Barton
- National Centre for Medical Genetics, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland ; University College Dublin UCD School of Medicine and Medical Sciences, Our Lady's Children's Hospital Crumlin, Dublin, 12, Ireland
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