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Cho SH, Jeong SH, Choi WH, Lee SY. Genomic Landscape of Branchio-Oto-Renal Syndrome through Whole-Genome Sequencing: A Single Rare Disease Center Experience in South Korea. Int J Mol Sci 2024; 25:8149. [PMID: 39125727 PMCID: PMC11311636 DOI: 10.3390/ijms25158149] [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: 07/03/2024] [Revised: 07/23/2024] [Accepted: 07/24/2024] [Indexed: 08/12/2024] Open
Abstract
Branchio-oto-renal (BOR) and branchio-otic (BO) syndromes are characterized by anomalies affecting the ears, often accompanied by hearing loss, as well as abnormalities in the branchial arches and renal system. These syndromes exhibit a broad spectrum of phenotypes and a complex genomic landscape, with significant contributions from the EYA1 gene and the SIX gene family, including SIX1 and SIX5. Due to their diverse phenotypic presentations, which can overlap with other genetic syndromes, molecular genetic confirmation is essential. As sequencing technologies advance, whole-genome sequencing (WGS) is increasingly used in rare disease diagnostics. We explored the genomic landscape of 23 unrelated Korean families with typical or atypical BOR/BO syndrome using a stepwise approach: targeted panel sequencing and exome sequencing (Step 1), multiplex ligation-dependent probe amplification (MLPA) with copy number variation screening (Step 2), and WGS (Step 3). Integrating WGS into our diagnostic pipeline detected structure variations, including cryptic inversion and complex genomic rearrangement, eventually enhancing the diagnostic yield to 91%. Our findings expand the genomic architecture of BOR/BO syndrome and highlight the need for WGS to address the genetic diagnosis of clinically heterogeneous rare diseases.
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Affiliation(s)
- Sung Ho Cho
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Republic of Korea; (S.H.C.); (S.H.J.); (W.H.C.)
| | - Sung Ho Jeong
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Republic of Korea; (S.H.C.); (S.H.J.); (W.H.C.)
| | - Won Hoon Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Republic of Korea; (S.H.C.); (S.H.J.); (W.H.C.)
| | - Sang-Yeon Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Republic of Korea; (S.H.C.); (S.H.J.); (W.H.C.)
- Department of Genomic Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
- Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul 03080, Republic of Korea
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2
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Yi H, Yun Y, Choi WH, Hwang HY, Cha JH, Seok H, Song JJ, Lee JH, Lee SY, Kim D. CRISPR-based editing strategies to rectify EYA1 complex genomic rearrangement linked to haploinsufficiency. MOLECULAR THERAPY. NUCLEIC ACIDS 2024; 35:102199. [PMID: 38766525 PMCID: PMC11101721 DOI: 10.1016/j.omtn.2024.102199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 04/21/2024] [Indexed: 05/22/2024]
Abstract
Pathogenic structure variations (SVs) are associated with various types of cancer and rare genetic diseases. Recent studies have used Cas9 nuclease with paired guide RNAs (gRNAs) to generate targeted chromosomal rearrangements, focusing on producing fusion proteins that cause cancer, whereas research on precision genome editing for rectifying SVs is limited. In this study, we identified a novel complex genomic rearrangement (CGR), specifically an EYA1 inversion with a deletion, implicated in branchio-oto-renal/branchio-oto syndrome. To address this, two CRISPR-based approaches were tested. First, we used Cas9 nuclease and paired gRNAs tailored to the patient's genome. The dual CRISPR-Cas9 system induced efficient correction of paracentric inversion in patient-derived fibroblast, and effectively restored the expression of EYA1 mRNA and protein, along with its transcriptional activity required to regulate the target gene expression. Additionally, we used CRISPR activation (CRISPRa), which leads to the upregulation of EYA1 mRNA expression in patient-derived fibroblasts. Moreover, CRISPRa significantly improved EYA1 protein expression and transcriptional activity essential for target gene expression. This suggests that CRISPRa-based gene therapies could offer substantial translational potential for approximately 70% of disease-causing EYA1 variants responsible for haploinsufficiency. Our findings demonstrate the potential of CRISPR-guided genome editing for correcting SVs, including those with EYA1 CGR linked to haploinsufficiency.
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Affiliation(s)
- Hwalin Yi
- Department of Precision Medicine, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Yejin Yun
- Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 03080, South Korea
| | - Won Hoon Choi
- Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 03080, South Korea
| | - Hye-Yeon Hwang
- Department of Precision Medicine, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Ju Hyuen Cha
- Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 03080, South Korea
| | - Heeyoung Seok
- Department of Transdisciplinary Research and Collaboration, Genomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, South Korea
| | - Jae-Jin Song
- Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Jun Ho Lee
- Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 03080, South Korea
| | - Sang-Yeon Lee
- Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 03080, South Korea
- Department of Genomic Medicine, Seoul National University Hospital, Seoul 03080, Republic of Korea
- Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul 03080, Republic of Korea
| | - Daesik Kim
- Department of Precision Medicine, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
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Chen A, Ling J, Peng X, Liu X, Mao S, Chen Y, Qin M, Zhang S, Bai Y, Song J, Feng Z, Ma L, He D, Mei L, He C, Feng Y. A Novel EYA1 Mutation Causing Alternative RNA Splicing in a Chinese Family With Branchio-Oto Syndrome: Implications for Molecular Diagnosis and Clinical Application. Clin Exp Otorhinolaryngol 2023; 16:342-358. [PMID: 37817567 DOI: 10.21053/ceo.2023.00668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 10/11/2023] [Indexed: 10/12/2023] Open
Abstract
OBJECTIVES Branchio-oto syndrome (BOS) primarily manifests as hearing loss, preauricular pits, and branchial defects. EYA1 is the most common pathogenic gene, and splicing mutations account for a substantial proportion of cases. However, few studies have addressed the structural changes in the protein caused by splicing mutations and potential pathogenic factors, and several studies have shown that middle-ear surgery has limited effectiveness in improving hearing in these patients. BOS has also been relatively infrequently reported in the Chinese population. This study explored the genetic etiology in the family of a proband with BOS and provided clinical treatment to improve the patient's hearing. METHODS We collected detailed clinical features and peripheral blood samples from the patients and unaffected individuals within the family. Pathogenic mutations were identified by whole-exome sequencing and cosegregation analysis and classified according to the American College of Medical Genetics and Genomics guidelines. Alternative splicing was verified through a minigene assay. The predicted three-dimensional protein structure and biochemical experiments were used to investigate the pathogenicity of the mutation. The proband underwent middle-ear surgery and was followed up at 1 month and 6 months postoperatively to monitor auditory improvement. RESULTS A novel heterozygous EYA1 splicing variant (c.1050+4 A>C) was identified and classified as pathogenic (PVS1(RNA), PM2, PP1). Skipping of exon 11 of the EYA1 pre-mRNA was confirmed using a minigene assay. This mutation may impair EYA1-SIX1 interactions, as shown by an immunoprecipitation assay. The EYA1-Mut protein exhibited cellular mislocalization and decreased protein expression in cytological experiments. Middle-ear surgery significantly improved hearing loss caused by bone-conduction abnormalities in the proband. CONCLUSION We reported a novel splicing variant of EYA1 in a Chinese family with BOS and revealed the potential molecular pathogenic mechanism. The significant hearing improvement observed in the proband after middle-ear surgery provides a reference for auditory rehabilitation in similar patients.
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Affiliation(s)
- Anhai Chen
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Jie Ling
- Medical Functional Experiment Center, School of Basic Medicine, Central South University, Changsha, China
| | - Xin Peng
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
- Department of Pathology, Xiangya Hospital, Central South University, Changsha, China
| | - Xianlin Liu
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Shuang Mao
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Yongjia Chen
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Mengyao Qin
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Shuai Zhang
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Yijiang Bai
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Jian Song
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Zhili Feng
- Department of Otorhinolaryngology, Head and Neck Surgery, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- MOE Key Lab of Rare Pediatric Diseases and Institute of Otorhinolaryngology, Head and Neck Surgery, University of South China, Changsha, China
| | - Lu Ma
- MOE Key Lab of Rare Pediatric Diseases and Institute of Otorhinolaryngology, Head and Neck Surgery, University of South China, Changsha, China
- The Hengyang Key Laboratory of Cellular Stress Biology, Institute of Cytology and Genetics, Hengyang Medical School, University of South China, Hengyang, China
| | - Dinghua He
- Department of Otorhinolaryngology, The Affiliated Maternal and Child Health Hospital of Hunan Province, Hengyang Medical School, University of South China, Changsha, China
| | - Lingyun Mei
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Chufeng He
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, China
- National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Yong Feng
- Department of Otorhinolaryngology, Xiangya Hospital, Central South University, Changsha, China
- Department of Otorhinolaryngology, Head and Neck Surgery, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- MOE Key Lab of Rare Pediatric Diseases and Institute of Otorhinolaryngology, Head and Neck Surgery, University of South China, Changsha, China
- Department of Otorhinolaryngology, The Affiliated Maternal and Child Health Hospital of Hunan Province, Hengyang Medical School, University of South China, Changsha, China
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4
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Cacciatori E, Aleo S, Scuvera G, Rigon C, Marchisio PG, Cassina M, Milani D. From clinical to molecular diagnosis: relevance of diagnostic strategy in two cases of branchio-oto-renal syndrome - case report. Ital J Pediatr 2022; 48:177. [PMID: 36183088 PMCID: PMC9526977 DOI: 10.1186/s13052-022-01369-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 09/09/2022] [Indexed: 12/02/2022] Open
Abstract
Background Branchio-oto-renal syndrome (BOR) is an autosomal dominant disorder characterized by deafness, branchiogenic malformations and renal abnormalities. Pathogenic variants in EYA1, SIX1 and SIX5 genes cause almost half of cases; copy number variants (CNV) and complex genomic rearrangements have been revealed in about 20% of patients, but they are not routinely and commonly included in the diagnostic work-up. Case presentation We report two unrelated patients with BOR syndrome clinical features, negative sequencing for BOR genes and the identification of a 2.65 Mb 8q13.2–13.3 microdeletion. Conclusions We highlight the value of CNV analyses in high level of suspicion for BOR syndrome but negative sequencing for BOR genes and we propose an innovative diagnostic flow-chart to increase current detection rate. Our report confirms a mechanism of non-allelic homologous recombination as causing this recurrent 8q13.2–13.3 microdeletion. Moreover, considering the role of PRDM14 and NCOA2 genes, both involved in regulation of fertility and deleted in our patients, we suggest the necessity of a longer follow-up to monitor fertility issues or additional clinical findings.
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Affiliation(s)
- Elena Cacciatori
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | | | - Giulietta Scuvera
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Chiara Rigon
- Clinical Genetics Unit, Department of Women's and Children's Health, University of Padova, Via Giustiniani, 3, 35128, Padova, Italy
| | - Paola Giovanna Marchisio
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Matteo Cassina
- Clinical Genetics Unit, Department of Women's and Children's Health, University of Padova, Via Giustiniani, 3, 35128, Padova, Italy.
| | - Donatella Milani
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
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5
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Xu J, Li J, Ramakrishnan A, Yan H, Shen L, Xu PX. Six1 and Six2 of the Sine Oculis Homeobox Subfamily are Not Functionally Interchangeable in Mouse Nephron Formation. Front Cell Dev Biol 2022; 10:815249. [PMID: 35178390 PMCID: PMC8844495 DOI: 10.3389/fcell.2022.815249] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/05/2022] [Indexed: 11/25/2022] Open
Abstract
The vertebrate Six1 and Six2 arose by gene duplication from the Drosophila sine oculis and have since diverged in their developmental expression patterns. Both genes are expressed in nephron progenitors of human fetal kidneys, and mutations in SIX1 or SIX2 cause branchio-oto-renal syndrome or renal hypodysplasia respectively. Since ∼80% of SIX1 target sites are shared by SIX2, it is speculated that SIX1 and SIX2 may be functionally interchangeable by targeting common downstream genes. In contrast, in mouse kidneys, Six1 expression in the metanephric mesenchyme lineage overlaps with Six2 only transiently, while Six2 expression is maintained in the nephron progenitors throughout development. This non-overlapping expression between Six1 and Six2 in mouse nephron progenitors promoted us to examine if Six1 can replace Six2. Surprisingly, forced expression of Six1 failed to rescue Six2-deficient kidney phenotype. We found that Six1 mediated Eya1 nuclear translocation and inhibited premature epithelialization of the progenitors but failed to rescue the proliferation defects and cell death caused by Six2-knockout. Genome-wide binding analyses showed that Six1 selectively occupied a small subset of Six2 target sites, but many Six2-bound loci crucial to the renewal and differentiation of nephron progenitors lacked Six1 occupancy. Altogether, these data indicate that Six1 cannot substitute Six2 to drive nephrogenesis in mouse kidneys, thus demonstrating that the difference in physiological roles of Six1 and Six2 in kidney development stems from both transcriptional regulations of the genes and divergent biochemical properties of the proteins.
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Affiliation(s)
- Jinshu Xu
- Department of Genetics and Genomic Sciences, New York, NY, United States
| | - Jun Li
- Department of Genetics and Genomic Sciences, New York, NY, United States
| | | | - Hanen Yan
- Department of Genetics and Genomic Sciences, New York, NY, United States
| | - Li Shen
- Department of Neurosciences, New York, NY, United States
| | - Pin-Xian Xu
- Department of Genetics and Genomic Sciences, New York, NY, United States.,Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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6
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Harris M, Schuh MP, McKinney D, Kaufman K, Erkan E. Whole Exome Sequencing in a Population With Severe Congenital Anomalies of Kidney and Urinary Tract. Front Pediatr 2022; 10:898773. [PMID: 35990004 PMCID: PMC9386178 DOI: 10.3389/fped.2022.898773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 06/01/2022] [Indexed: 11/25/2022] Open
Abstract
Fetal and neonatal interventions (e.g., amnioinfusions, amniotic shunting, and infant dialysis) have increased survival of infants with severe Congenital Anomalies of the Kidney and Urinary Tract (CAKUT), however, outcomes vary dramatically. Our aim was to perform Whole Exome Sequencing (WES) in a unique severe CAKUT population with the goal to identify new variants that will enhance prediction of postnatal outcomes. We performed trio WES on five infants with severe CAKUT (undergoing fetal interventions and/or those who initiated renal replacement therapy (RRT) within 1 month of life) and their parents as well as three singletons. We identified three potential candidate gene variants (NSUN7, MTMR3, CEP162) and validated two variants in known CAKUT genes (GATA3 and FRAS1) showing strong enrichment in this severe phenotype population. Based on our small pilot study of a unique severe CAKUT population, WES appears to be a potential tool to help predict the course of infants with severe CAKUT prenatally.
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Affiliation(s)
- Meredith Harris
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Division of Nephrology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States
| | - Meredith P Schuh
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - David McKinney
- University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Kenneth Kaufman
- Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Elif Erkan
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,University of Cincinnati College of Medicine, Cincinnati, OH, United States
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7
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The Eyes Absent proteins in development and in developmental disorders. Biochem Soc Trans 2021; 49:1397-1408. [PMID: 34196366 PMCID: PMC8286820 DOI: 10.1042/bst20201302] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/06/2021] [Accepted: 06/07/2021] [Indexed: 11/23/2022]
Abstract
The Eyes Absent (EYA) transactivator-phosphatase proteins are important contributors to cell-fate determination processes and to the development of multiple organs. The transcriptional regulatory activity as well as the protein tyrosine phosphatase activities of the EYA proteins can independently contribute to proliferation, differentiation, morphogenesis and tissue homeostasis in different contexts. Aberrant EYA levels or activity are associated with numerous syndromic and non-syndromic developmental disorders, as well as cancers. Commensurate with the multiplicity of biochemical activities carried out by the EYA proteins, they impact upon a range of cellular signaling pathways. Here, we provide a broad overview of the roles played by EYA proteins in development, and highlight the molecular signaling pathways known to be linked with EYA-associated organ development and developmental disorders.
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8
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Han R, Xia Y, Liu Z, Wu S, Ye E, Duan L, Ding J, La X. A mutation of EYA1 gene in a Chinese Han family with Branchio-Oto syndrome. Medicine (Baltimore) 2021; 100:e24691. [PMID: 34160378 PMCID: PMC8238333 DOI: 10.1097/md.0000000000024691] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 01/21/2021] [Indexed: 01/04/2023] Open
Abstract
Branchio-Oto (BO) syndrome is one of the common syndromic forms of hearing loss. In this study, we aimed to characterize the clinical and genetic features of BO syndrome in a Chinese deaf family.The proposita in this study was a 29-years-old Chinese female with hearing loss, microtia, anterior concave auricle, and right branchial fistula. The family members agreed to undergo clinical examination. We collected blood samples from 7 family members, including 4 affected by the syndrome. Genomic DNA was extracted and subjected to Sanger sequencing. In addition, bioinformatics software SWISS MODEL was used to predict the protein encoded by EYA transcriptional coactivator and phosphatase 1 (EYA1) gene.Intra-familial consistency can be observed in the clinical phenotypes of BO syndrome in this family. EYA1 c.1627C>T (p.Gln543Ter) mutation was identified as the pathogenic cause in this family.This study reports a mutation associated with BO syndrome in a Chinese Han family. We highlight the utility of genetic testing in the diagnosis of BO syndrome. Thus, we believe that this report would provide a basis for the diagnosis of similar diseases in the future.
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Affiliation(s)
- Rui Han
- Department of Prenatal Diagnosis, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University
- Department of Immunology, College of Basic Medicine
- State Key Laboratory of Pathogenesis, Prevention, Treatment of Central Asian High incidence Diseases, Xinjiang Medical University, Urumqi, Xinjiang, China
| | - Yan Xia
- Department of Prenatal Diagnosis, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University
| | - Zhijuan Liu
- Department of Prenatal Diagnosis, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University
| | - Shuang Wu
- Department of Prenatal Diagnosis, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University
| | - Erdengqieqieke Ye
- Department of Prenatal Diagnosis, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University
| | - Ling Duan
- Department of Prenatal Diagnosis, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University
| | - Jianbing Ding
- Department of Immunology, College of Basic Medicine
- State Key Laboratory of Pathogenesis, Prevention, Treatment of Central Asian High incidence Diseases, Xinjiang Medical University, Urumqi, Xinjiang, China
| | - Xiaolin La
- Department of Prenatal Diagnosis, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University
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9
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Chen A, Song J, Acke FRE, Mei L, Cai X, Feng Y, He C. Otological manifestations in branchiootorenal spectrum disorder: A systematic review and meta-analysis. Clin Genet 2021; 100:3-13. [PMID: 33624842 DOI: 10.1111/cge.13949] [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: 12/13/2020] [Revised: 02/09/2021] [Accepted: 02/20/2021] [Indexed: 11/30/2022]
Abstract
Branchiootorenal spectrum disorder (BORSD) is a group of rare autosomal dominant entities characterized by branchiogenic malformations, hearing loss (HL) and renal anomalies. It comprises branchiootorenal syndrome and branchiootic syndrome, distinguished by the presence or absence of renal abnormalities. Pathogenic variants have been discovered in the following genes: EYA1, SIX5, SIX1 and SALL1. As the otological phenotype in BORSD is inconsistently reported, we performed a systematic review to provide an up-to-date overview, correlated with the genotype. Forty publications were included, describing 295 individual patients. HL was diagnosed in 95%, usually bilateral and mixed-type, and differed among the different genes involved. Mixed moderate-to-severe HL was the predominant finding in patients with EYA1 involvement, regardless of the presence of renal abnormalities. The sensorineural HL of profound severity was more prevalent in patients with SIX1 mutations. No significant differences among different mutation types or location within the genes could be observed. Structural otological manifestations, ranging from periauricular to inner ear anomalies, were common in both genes. Especially periauricular anomalies were more common and more severe in EYA1. In summary, otological differences among the different genes involved in BORSD are observed, so the molecular analysis is strongly advised.
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Affiliation(s)
- Anhai Chen
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, Hunan, China.,Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, Hunan, China.,National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jian Song
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, Hunan, China.,Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, Hunan, China.,National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Frederic R E Acke
- Department of Otorhinolaryngology, Ghent University/Ghent University Hospital, Ghent, Belgium
| | - Lingyun Mei
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, Hunan, China.,Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, Hunan, China.,National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xinzhang Cai
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, Hunan, China.,Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, Hunan, China.,National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yong Feng
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, Hunan, China.,Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, Hunan, China.,Department of Otorhinolaryngology, Changsha Central Hospital, University of South China, Changsha, Hunan, China
| | - Chufeng He
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, Hunan, China.,Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, Hunan, China.,National Clinical Research Centre for Geriatric Disorders, Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan, China
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Klingbeil KD, Greenland CM, Arslan S, Paneque AL, Gurkan H, Ulusal SD, Maroofian R, Carrera-Gonzalez A, Montufar-Armendariz S, Paredes R, Elcioglu N, Menendez I, Behnam M, Foster J, Guo S, Escarfuller S, Cengiz FB, Duman D, Bademci G, Tekin M. Novel EYA1 variants causing Branchio-oto-renal syndrome. Int J Pediatr Otorhinolaryngol 2017; 98:59-63. [PMID: 28583505 PMCID: PMC5516569 DOI: 10.1016/j.ijporl.2017.04.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 04/16/2017] [Indexed: 01/19/2023]
Abstract
INTRODUCTION Branchio-oto-renal (BOR) syndrome is an autosomal dominant genetic disorder characterized by second branchial arch anomalies, hearing impairment, and renal malformations. Pathogenic mutations have been discovered in several genes such as EYA1, SIX5, and SIX1. However, nearly half of those affected reveal no pathogenic variant by traditional genetic testing. METHODS AND MATERIALS Whole Exome sequencing and/or Sanger sequencing performed in 10 unrelated families from Turkey, Iran, Ecuador, and USA with BOR syndrome in this study. RESULTS We identified causative DNA variants in six families including novel c.525delT, c.979T > C, and c.1768delG and a previously reported c.1779A > T variants in EYA1. Two large heterozygous deletions involving EYA1 were detected in additional two families. Whole exome sequencing did not reveal a causative variant in the remaining four families. CONCLUSIONS A variety of DNA changes including large deletions underlie BOR syndrome in different populations, which can be detected with comprehensive genetic testing.
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Affiliation(s)
- Kyle D. Klingbeil
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Christopher M. Greenland
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Selcuk Arslan
- Karadeniz Technical University, Faculty of medicine, Department of ENT, Trabzon, Turkey
| | | | - Hakan Gurkan
- Trakya University, School of Medicine, Department of medical Genetics, Edirne, Turkey
| | - Selma Demir Ulusal
- Trakya University, School of Medicine, Department of medical Genetics, Edirne, Turkey
| | - Reza Maroofian
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, RILD Wellcome Wolfson Centre, Exeter, UK
| | | | | | | | - Nursel Elcioglu
- Department of Pediatric Genetics, Marmara University Medical School, Istanbul, Turkey
| | - Ibis Menendez
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | | | - Joseph Foster
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Shengru Guo
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Sebastian Escarfuller
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Filiz Basak Cengiz
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Duygu Duman
- Division of Genetics, Department of Pediatrics, Ankara University School of Medicine, Ankara, Turkey
| | - Guney Bademci
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Mustafa Tekin
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA; Dr. John T. Macdonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL, USA.
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Genetic Effects on Sensorineural Hearing Loss and Evidence-based Treatment for Sensorineural Hearing Loss. ACTA ACUST UNITED AC 2016; 30:179-88. [PMID: 26564418 DOI: 10.1016/s1001-9294(15)30044-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In this article, the mechanism of inheritance behind inherited hearing loss and genetic susceptibility in noise-induced hearing loss are reviewed. Conventional treatments for sensorineural hearing loss (SNHL), i.e. hearing aid and cochlear implant, are effective for some cases, but not without limitations. For example, they provide little benefit for patients of profound SNHL or neural hearing loss, especially when the hearing loss is in poor dynamic range and with low frequency resolution. We emphasize the most recent evidence-based treatment in this field, which includes gene therapy and allotransplantation of stem cells. Their promising results have shown that they might be options of treatment for profound SNHL and neural hearing loss. Although some treatments are still at the experimental stage, it is helpful to be aware of the novel therapies and endeavour to explore the feasibility of their clinical application.
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dos Santos Junior ACS, de Miranda DM, Simões e Silva AC. Congenital anomalies of the kidney and urinary tract: An embryogenetic review. ACTA ACUST UNITED AC 2014; 102:374-81. [DOI: 10.1002/bdrc.21084] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 10/27/2014] [Indexed: 11/10/2022]
Affiliation(s)
| | - Debora Marques de Miranda
- National Institute of Science and Technology-Molecular Medicine (INCT-MM), Universidade Federal de Minas Gerais (UFMG); Brazil
- Faculty of Medicine; Department of Pediatrics; Unit of Pediatric Nephrology; Pediatric Branch of the Interdisciplinary Laboratory of Medical Investigation, UFMG; Brazil
| | - Ana Cristina Simões e Silva
- National Institute of Science and Technology-Molecular Medicine (INCT-MM), Universidade Federal de Minas Gerais (UFMG); Brazil
- Faculty of Medicine; Department of Pediatrics; Unit of Pediatric Nephrology; Pediatric Branch of the Interdisciplinary Laboratory of Medical Investigation, UFMG; Brazil
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Chen X, Wang J, Mitchell E, Guo J, Wang L, Zhang Y, Hodge JC, Shen Y. Recurrent 8q13.2-13.3 microdeletions associated with branchio-oto-renal syndrome are mediated by human endogenous retroviral (HERV) sequence blocks. BMC MEDICAL GENETICS 2014; 15:90. [PMID: 25135225 PMCID: PMC4152767 DOI: 10.1186/s12881-014-0090-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 07/18/2014] [Indexed: 01/18/2023]
Abstract
Background Human endogenous retroviral (HERV) sequences are the remnants of ancient retroviral infection and comprise approximately 8% of the human genome. The high abundance and interspersed nature of homologous HERV sequences make them ideal substrates for genomic rearrangements. A role for HERV sequences in mediating human disease-associated rearrangement has been reported but is likely currently underappreciated. Methods and Results In the present study, two independent de novo 8q13.2-13.3 microdeletion events were identified in patients with clinical features of Branchio-Oto-Renal (BOR) syndrome. Nucleotide-level mapping demonstrated the identical breakpoints, suggesting a recurrent microdeletion including multiple genes such as EYA1, SULF1, and SLCO5A1, which is mediated by HERV1 homologous sequences. Conclusions These findings raise the potential that HERV sequences may more commonly underlie recombination of dosage sensitive regions associated with recurrent syndromes.
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Lindau TA, Cardoso ACV, Rossi NF, Giacheti CM. Anatomical Changes and Audiological Profile in Branchio-oto-renal Syndrome: A Literature Review. Int Arch Otorhinolaryngol 2013; 18:68-76. [PMID: 25992067 PMCID: PMC4296951 DOI: 10.1055/s-0033-1358659] [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: 08/27/2013] [Accepted: 09/04/2013] [Indexed: 01/26/2023] Open
Abstract
Introduction Branchio-oto-renal (BOR) syndrome is an autosomal-dominant genetic condition with high penetrance and variable expressivity, with an estimated prevalence of 1 in 40,000. Approximately 40% of the patients with the syndrome have mutations in the gene EYA1, located at chromosomal region 8q13.3, and 5% have mutations in the gene SIX5 in chromosome region 19q13. The phenotype of this syndrome is characterized by preauricular fistulas; structural malformations of the external, middle, and inner ears; branchial fistulas; renal disorders; cleft palate; and variable type and degree of hearing loss. Aim Hearing loss is part of BOR syndrome phenotype. The aim of this study was to present a literature review on the anatomical aspects and audiological profile of BOR syndrome. Data Synthesis Thirty-four studies were selected for analysis. Some aspects when specifying the phenotype of BOR syndrome are controversial, especially those issues related to the audiological profile in which there was variability on auditory standard, hearing loss progression, and type and degree of the hearing loss. Mixed loss was the most common type of hearing loss among the studies; however, there was no consensus among studies regarding the degree of the hearing loss.
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Affiliation(s)
- Tâmara Andrade Lindau
- Department of Speech Pathology, Universidade Estadual Paulista - UNESP, Marília, São Paulo, Brazil
| | | | - Natalia Freitas Rossi
- Department of Speech Pathology, Universidade Estadual Paulista - UNESP, Marília, São Paulo, Brazil
| | - Célia Maria Giacheti
- Department of Speech Pathology, Universidade Estadual Paulista - UNESP, Marília, São Paulo, Brazil
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Schmidt T, Bierhals T, Kortüm F, Bartels I, Liehr T, Burfeind P, Shoukier M, Frank V, Bergmann C, Kutsche K. Branchio-Otic Syndrome Caused by a Genomic Rearrangement: Clinical Findings and Molecular Cytogenetic Studies in a Patient with a Pericentric Inversion of Chromosome 8. Cytogenet Genome Res 2013; 142:1-6. [DOI: 10.1159/000355436] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2013] [Indexed: 11/19/2022] Open
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Balancing cell numbers during organogenesis: Six1a differentially affects neurons and sensory hair cells in the inner ear. Dev Biol 2011; 357:191-201. [PMID: 21745464 DOI: 10.1016/j.ydbio.2011.06.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2011] [Revised: 05/31/2011] [Accepted: 06/14/2011] [Indexed: 11/20/2022]
Abstract
While genes involved in the differentiation of the mechanosensory hair cells and the neurons innervating them have been identified, genes involved in balancing their relative numbers remain unknown. Six1a plays a dual role by promoting hair cell fate while inhibiting neuronal fate in these two lineages. Genes homologous to six1a act as either transcriptional activators or repressors, depending on the partners with which they interact. By assaying the in vivo and in vitro effects of mutations in presumptive protein-protein interacting and DNA-binding domains of Six1a, we show that, in the developing zebrafish inner ear, Six1a promotes hair cell fate by acting as a transcriptional activator and inhibits neuronal fate by acting as a transcriptional repressor. We also identify several potential partners for Six1a that differ between these two lineages. The dual role of Six1a in the developing otocyst provides a mechanism for balancing the relative number of hair cells and neurons during organogenesis of the inner ear.
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17
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Sanchez-Valle A, Wang X, Potocki L, Xia Z, Kang SHL, Carlin ME, Michel D, Williams P, Cabrera-Meza G, Brundage EK, Eifert AL, Stankiewicz P, Cheung SW, Lalani SR. HERV-mediated genomic rearrangement of EYA1 in an individual with branchio-oto-renal syndrome. Am J Med Genet A 2011; 152A:2854-60. [PMID: 20979191 DOI: 10.1002/ajmg.a.33686] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Branchio-oto-renal syndrome is characterized by branchial defects, hearing loss, preauricular pits, and renal anomalies. Mutations in EYA1 are the most common cause of branchio-oto-renal and branchio-otic syndromes. Large chromosomal aberrations of 8q13, including complex rearrangements occur in about 20% of these individuals. However, submicroscopic deletions and the molecular characterization of genomic rearrangements involving the EYA1 gene have rarely been reported. Using the array-comparative genomic hybridization, we identified non-recurrent genomic deletions including the EYA1 gene in three patients with branchio-oto-renal syndrome, short stature, and developmental delay. One of these deletions was mediated by two human endogenous retroviral sequence blocks, analogous to the AZFa microdeletion on Yq11, responsible for male infertility. This report describes the expanded phenotype of individuals, resulting from contiguous gene deletion involving the EYA1 gene and provides a molecular description of the genomic rearrangements involving this gene in branchio-oto-renal syndrome.
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Affiliation(s)
- Amarilis Sanchez-Valle
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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18
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Morisada N, Rendtorff ND, Nozu K, Morishita T, Miyakawa T, Matsumoto T, Hisano S, Iijima K, Tranebjaerg L, Shirahata A, Matsuo M, Kusuhara K. Branchio-oto-renal syndrome caused by partial EYA1 deletion due to LINE-1 insertion. Pediatr Nephrol 2010; 25:1343-8. [PMID: 20130917 DOI: 10.1007/s00467-010-1445-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2009] [Revised: 12/14/2009] [Accepted: 12/16/2009] [Indexed: 01/15/2023]
Abstract
A 7-year-old Japanese girl with conductive deafness and preauricular fistulae developed proteinuria. She had renal insufficiency, and ultrasound revealed bilateral small kidneys. These findings indicated that she had branchio-oto-renal (BOR) syndrome. In the present patient, we identified, by using multiplex ligation-dependent probe amplification (MLPA) analysis, a heterozygous EYA1 gene deletion comprising at least exons 5 to 7. In her parents, we did not detect any deletion in EYA1 by MLPA, so the deletion was a de novo mutation. PCR analysis and sequencing of patient DNA revealed a heterozygous approximately 17 kb EYA1 deletion starting from the eight last bases of exon 4 and proceeding to base 1,217 of intron 7. Furthermore, in place of this deleted region was inserted a 3756-bp-long interspersed nuclear elements-1 (LINE-1, L1). Accordingly, RT-PCR showed that exons 4-7 were not present in EYA1 mRNA expressed from the mutated allele. Although there are reports of L1 element insertion occurring in various human diseases, this is the first report of a large EYA1 deletion in combination with L1 element insertion.
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Affiliation(s)
- Naoya Morisada
- Department of Pediatrics, Saiseikai Yahata General Hospital, 5-9-27, Haruno-machi, Yahatahigashi-ku, Kitakyushu, Fukuoka, 805-0050, Japan.
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Zhang F, Carvalho CMB, Lupski JR. Complex human chromosomal and genomic rearrangements. Trends Genet 2009; 25:298-307. [PMID: 19560228 DOI: 10.1016/j.tig.2009.05.005] [Citation(s) in RCA: 199] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Revised: 05/14/2009] [Accepted: 05/19/2009] [Indexed: 01/08/2023]
Abstract
Copy number variation (CNV) is a major source of genetic variation among humans. In addition to existing as benign polymorphisms, CNVs can also convey clinical phenotypes, including genomic disorders, sporadic diseases and complex human traits. CNV results from genomic rearrangements that can represent simple deletion or duplication of a genomic segment, or be more complex. Complex chromosomal rearrangements (CCRs) have been known for some time but their mechanisms have remained elusive. Recent technology advances and high-resolution human genome analyses have revealed that complex genomic rearrangements can account for a large fraction of non-recurrent rearrangements at a given locus. Various mechanisms, most of which are DNA-replication-based, for example fork stalling and template switching (FoSTeS) and microhomology-mediated break-induced replication (MMBIR), have been proposed for generating such complex genomic rearrangements and are probably responsible for CCR.
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Affiliation(s)
- Feng Zhang
- Department of Molecular and Human Genetics, Baylor College of Medicine, and Texas Children's Hospital, Houston, TX 77030, USA
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20
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Goodin K, Prucka S, Woolley AL, Kohlhase J, Smith RJ, Grant J, Robin NH. Familial transmission of oculoauriculovertebral spectrum (Goldenhar syndrome) is not due to mutations in either EYA1 or SALL1. Am J Med Genet A 2009; 149A:535-8. [DOI: 10.1002/ajmg.a.32673] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Garin I, Rica I, Estalella I, Oyarzabal M, Rodríguez-Rigual M, San Pedro JI, Pérez-Nanclares G, Fernández-Rebollo E, Busturia MA, Castaño L, Pérez de Nanclares G. Haploinsufficiency at GCK gene is not a frequent event in MODY2 patients. Clin Endocrinol (Oxf) 2008; 68:873-8. [PMID: 18248649 DOI: 10.1111/j.1365-2265.2008.03214.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of this study was to characterize glucokinase (GCK) alterations in maturity-onset diabetes of the young 2 (MODY2)-suspected patients and to investigate their clinical characteristics in relation to the parental origin of the mutation. PATIENTS AND METHODS We studied a group of 57 unrelated Spanish patients presenting with MODY2 phenotype. Patients without mutation in the coding region of the GCK gene were screened for rearrangements by Multiplex Ligation-dependent Probe Amplification (MLPA). After classification according to the parental origin of the mutation, clinical characteristics were compared between the groups. RESULTS We detected a point mutation or small deletion or insertion of the GCK gene in 47 patients (82.5%); 19 mutations were novel. In addition, we found a whole-gene deletion by MLPA. Patients carrying a GCK gene defect and those with MODY of unknown genetic origin shows similar phenotypes. Comparison of clinical parameters according to the origin of the mutation did not show any differences in the birth weight (BW) nor in age at diagnosis. Patients who inherited the mutation from the father had higher fasting glucose levels at diagnosis. CONCLUSION Although the presence of haploinsufficiency of GCK is not a common cause of MODY2, gene dose analysis should be performed when no mutation is found. Strict maternal euglycaemia can contribute to intrauterine growth restriction and low BW when the foetus has inherited the GCK mutation from the mother. As foetal genotype in generally is not known, serial foetal abdominal scans may act as a surrogate for this.
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Affiliation(s)
- Intza Garin
- Endocrinology and Diabetes Research Group, Hospital de Cruces, Barakaldo, Basque Country, Spain
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Orten DJ, Fischer SM, Sorensen JL, Radhakrishna U, Cremers CW, Marres HA, Van Camp G, Welch KO, Smith RJ, Kimberling WJ. Branchio-oto-renal syndrome (BOR): novel mutations in theEYA1gene, and a review of the mutational genetics of BOR. Hum Mutat 2008; 29:537-44. [DOI: 10.1002/humu.20691] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Abstract
Branchio-oto-renal syndrome, a phenotype consisting of hearing loss, auricular malformations, branchial arch remnants, and renal anomalies is now recognized as one of the more common forms of autosomal dominant syndromic hearing impairment. Three loci known to be associated with the BOR phenotype have been identified and two genes that act in a regulatory network have been cloned, EYA1 and SIX1. EYA1 and SIX1 are homologous to genes involved in Drosophila eye development, eyes absent gene (eya), and sine oculis (so), respectively. EYA1, a transcriptional co-activator has a conserved, 271-amino acid, C-terminal known as the Eya Domain (ED). SIX1 has two highly conserved domains; a homeodomain (HD) and a specific Six-domain (SD) whose products function as transcription factors with specific DNA-binding activity that are crucial for protein-protein interaction. To determine the molecular basis for the organ defects that occur in BOR syndrome, many studies have focused on the effects of mutations to EYA and effects of mutations of the EYA-SIX regulatory system. However, over 60% of BOR syndrome patients do not have known mutations in EYA1 and relatively little is known about mutations to SIX1. Further evaluation of SIX1 and its related target genes may provide a better understanding of the pathophysiology of BOR syndrome and offer greater clues to the disease mechanisms.
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Affiliation(s)
- Amit Kochhar
- Molecular Otolaryngology Research Laboratories, University of Iowa, Iowa City, Iowa 52242, USA
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Sanggaard KM, Rendtorff ND, Kjaer KW, Eiberg H, Johnsen T, Gimsing S, Dyrmose J, Nielsen KO, Lage K, Tranebjaerg L. Branchio-oto-renal syndrome: detection of EYA1 and SIX1 mutations in five out of six Danish families by combining linkage, MLPA and sequencing analyses. Eur J Hum Genet 2007; 15:1121-31. [PMID: 17637804 DOI: 10.1038/sj.ejhg.5201900] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The branchio-oto-renal (BOR) syndrome is an autosomal-dominant disorder characterized by hearing loss, branchial and renal anomalies. BOR is genetically heterogeneous and caused by mutations in EYA1 (8q13.3), SIX1 (14q23.1), SIX5 (19q13.3) and in an unidentified gene on 1q31. We examined six Danish families with BOR syndrome by assessing linkage to BOR loci, by performing EYA1 multiplex ligation-dependent probe amplification (MLPA) analysis for deletions and duplications and by sequencing of EYA1, SIX1 and SIX5. We identified four EYA1 mutations (c.920delG, IVS10-1G>A, IVS12+4A>G and p.Y591X) and one SIX1 mutation (p.W122R), providing a molecular diagnosis in five out of the six families (83%). The present, yet preliminary, observation that renal and temporal bone malformations are less frequent in SIX1-related disease suggests a slightly different clinical profile compared to EYA1-related disease. Unidentified mutations impairing mRNA expression or further genetic heterogeneity may explain the lack of mutation finding in one family despite LOD score indications of EYA1 involvement.
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Affiliation(s)
- Kirsten Marie Sanggaard
- Wilhelm Johannsen Centre for Functional Genome Research, Section of Genetics, Institute of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
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Hoskins BE, Cramer CH, Silvius D, Zou D, Raymond RM, Orten DJ, Kimberling WJ, Smith RJH, Weil D, Petit C, Otto EA, Xu PX, Hildebrandt F. Transcription factor SIX5 is mutated in patients with branchio-oto-renal syndrome. Am J Hum Genet 2007; 80:800-4. [PMID: 17357085 PMCID: PMC1852719 DOI: 10.1086/513322] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Accepted: 01/25/2007] [Indexed: 11/04/2022] Open
Abstract
Branchio-oto-renal syndrome (BOR) is an autosomal dominant developmental disorder characterized by the association of branchial arch defects, hearing loss, and renal anomalies. Mutations in EYA1 are known to cause BOR. More recently, mutations in SIX1, which interacts with EYA1, were identified as an additional cause of BOR. A second member of the SIX family of proteins, unc-39 (SIX5), has also been reported to directly interact with eya-1 in Caenorhabditis elegans. We hypothesized that this interaction would be conserved in humans and that interactors of EYA1 represent good candidate genes for BOR. We therefore screened a cohort of 95 patients with BOR for mutations in SIX5. Four different heterozygous missense mutations were identified in five individuals. Functional analyses of these mutations demonstrated that two mutations affect EYA1-SIX5 binding and the ability of SIX5 or the EYA1-SIX5 complex to activate gene transcription. We thereby identified heterozygous mutations in SIX5 as a novel cause of BOR.
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Clarke JC, Honey EM, Bekker E, Snyman LC, Raymond RM, Lord C, Brophy PD. A novel nonsense mutation in the EYA1 gene associated with branchio-oto-renal/branchiootic syndrome in an Afrikaner kindred. Clin Genet 2006; 70:63-7. [PMID: 16813606 DOI: 10.1111/j.1399-0004.2006.00642.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by the associations of hearing loss, branchial arch defects and renal anomalies. Branchiootic (BO) syndrome is a related disorder that presents without the highly variable characteristic renal anomalies of BOR syndrome. Dominant mutations in the human homologue of the Drosophila eyes absent gene (EYA1) are frequently the cause of both BOR and BO syndromes. We report a South African family of Afrikaner descent with affected individuals presenting with pre-auricular abnormalities and either hearing loss or bilateral absence of the kidneys. Genetic analysis of the pedigree detected a novel EYA1 heterozygous nonsense mutation in affected family members but not in unaffected family members or a random DNA panel. Through mutational analysis, we conclude that this particular mutation is the cause of BOR/BO syndrome in this family as a result of a truncation of the EYA1 protein that ablates the critical EYA homologous region. To the best of our knowledge, this is the first case of BOR/BO syndrome reported in Africa or in those of the Afrikaner descent.
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Affiliation(s)
- J C Clarke
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI 48109, USA.
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Fernandez P, Moolman-Smook J, Brink P, Corfield V. A gene locus for progressive familial heart block type II (PFHBII) maps to chromosome 1q32.2-q32.3. Hum Genet 2005; 118:133-7. [PMID: 16086176 DOI: 10.1007/s00439-005-0029-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2005] [Accepted: 06/27/2005] [Indexed: 01/04/2023]
Abstract
Cardiac conduction defects that are associated with dilated cardiomyopathy (DCM) are generally considered to be sporadic clinical entities, although familial forms of disorders with these clinical features have been identified in a number of families in different countries. An autosomal dominant cardiac disorder characterised by conduction abnormalities and DCM, termed progressive familial heart block type II (PFHBII) (OMIM 140400), has been described in a South African Caucasian family of Northern European descent. Known candidate loci for isolated conduction disorders, isolated DCM and conduction disorders complicated by DCM were excluded from disease causation in this family by linkage analysis, with the exception of the DCM-associated (CMD1D) locus on chromosome 1q32, where a maximum multipoint lod score of 3.7 in the interval between D1S3753 and D1S414, was generated. This region encompassed the troponin T gene (TNNT2), however, genetic fine mapping and haplotype analysis excluded TNNT2 as cause of PFHBII and placed the disease-causative gene within a 3.9 cM (2.85 Mb) interval, flanked by D1S70 and D1S505. Analysis of KCNH1, KIAA0205, LAMB3 and PPP2R5A, which map within the critical interval, indicated that the PFHBII-causative mutation does not lie within the coding regions or splice junctions of these plausible candidate genes. The data indicate the existence of a novel locus involved in the pathogenesis of cardiac conduction abnormalities and DCM.
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Affiliation(s)
- Pedro Fernandez
- US/MRC Centre for Molecular and Cellular Biology and Department of Medical Biochemistry, University of Stellenbosch Faculty of Health Sciences, PO Box 19063, Tygerberg, 7505, South Africa
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Boonen SE, Stahl D, Kreiborg S, Rosenberg T, Kalscheuer V, Larsen LA, Tommerup N, Brøndum-Nielsen K, Tümer Z. Delineation of an interstitial 9q22 deletion in basal cell nevus syndrome. Am J Med Genet A 2005; 132A:324-8. [PMID: 15690381 DOI: 10.1002/ajmg.a.30422] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Basal cell nevus syndrome (Gorlin syndrome) is an autosomal dominant disorder characterized by the presence of multiple basal cell carcinomas (BCC), odontogenic keratocysts, palmoplantar pits, and calcification in the falx cerebri caused by mutational inactivation of the PTCH gene. In few cases, the syndrome is due to a microdeletion at 9q22. Using high-resolution chromosome analysis we have identified a patient with the karyotype, 46,XY,del(9)(q21.3q31) de novo. He had typical clinical features consistent with basal cell nevus syndrome, but also additional features likely to be caused by loss of additional chromosomal material in this region. The deletion breakpoints were characterized with fluorescence in situ hybridization (FISH) analysis using BAC clones. The 15 Mb long deletion includes 87 RefSeq genes including PTCH. Hemizygosity of one or more genes might contribute to the additional symptoms observed in this patient.
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Affiliation(s)
- S E Boonen
- The John F. Kennedy Institute, Glostrup, Denmark
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29
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Henriksen AM, Tümer Z, Tommerup N, Tranebjaerg L, Larsen LA. Identification of a NovelEYA1Splice-Site Mutation in a Danish Branchio-Oto-Renal Syndrome Family. ACTA ACUST UNITED AC 2004; 8:404-6. [PMID: 15684871 DOI: 10.1089/gte.2004.8.404] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by variable clinical manifestations including branchial fistulae, preauricular pits, ear malformations, hearing impairment, and renal anomalies. BOR is caused by mutations in the genes EYA1 and SIX1. A Danish BOR family with five affected individuals in three generations was analyzed for mutations in all 17 exons of EYA1 using direct sequencing of polymerase chain reaction (PCR) amplified genomic DNA. A novel splice-site mutation (IVS9+1 G>C) was detected in all affected family members but not in unaffected family members or in 96 controls. We conclude that this mutation is causing BOR in the family, most likely as a result of haploinsufficiency or an abnormal protein product caused by aberrant splicing of EYA1 mRNA.
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Affiliation(s)
- Ann Marie Henriksen
- Willhelm Johansen Centre for Functional Genome Research, Department of Medical Biochemistry and Genetics, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
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Chang EH, Menezes M, Meyer NC, Cucci RA, Vervoort VS, Schwartz CE, Smith RJH. Branchio-oto-renal syndrome: the mutation spectrum in EYA1 and its phenotypic consequences. Hum Mutat 2004; 23:582-9. [PMID: 15146463 DOI: 10.1002/humu.20048] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
EYA1 mutations cause branchio-oto-renal (BOR) syndrome. These mutations include single nucleotide transitions and transversions, small duplications and deletions, and complex genomic rearrangements. The last cannot be detected by coding sequence analysis of EYA1. We sought to refine the clinical diagnosis of BOR syndrome by analyzing phenotypic data from families segregating EYA1 disease-causing mutations. Based on genotype-phenotype analyses, we propose new criteria for the clinical diagnosis of BOR syndrome. We found that in approximately 40% of persons meeting our criteria, EYA1 mutations were identified. Of these mutations, 80% were coding sequence variants identified by SSCP, and 20% were complex genomic rearrangements identified by a semiquantitative PCR-based screen. We conclude that genetic testing of EYA1 should include analysis of the coding sequence and a screen for complex rearrangements.
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Affiliation(s)
- Eugene H Chang
- Molecular Otolaryngology Research Labs, University of Iowa, Iowa City, Iowa 52242, USA
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31
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Martínez I, Rosa M, Arsuaga JL, Jarabo P, Quam R, Lorenzo C, Gracia A, Carretero JM, Bermúdez de Castro JM, Carbonell E. Auditory capacities in Middle Pleistocene humans from the Sierra de Atapuerca in Spain. Proc Natl Acad Sci U S A 2004; 101:9976-81. [PMID: 15213327 PMCID: PMC454200 DOI: 10.1073/pnas.0403595101] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human hearing differs from that of chimpanzees and most other anthropoids in maintaining a relatively high sensitivity from 2 kHz up to 4 kHz, a region that contains relevant acoustic information in spoken language. Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history. Here we use a comprehensive physical model to analyze the influence of skeletal structures on the acoustic filtering of the outer and middle ears in five fossil human specimens from the Middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca of Spain. Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5 kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range.
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Affiliation(s)
- I Martínez
- Departamento de Geología, Universidad de Alcalá, Edificio de Ciencias, Campus Universitario, 28871 Alcalá de Henares, Spain.
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32
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Ruf RG, Xu PX, Silvius D, Otto EA, Beekmann F, Muerb UT, Kumar S, Neuhaus TJ, Kemper MJ, Raymond RM, Brophy PD, Berkman J, Gattas M, Hyland V, Ruf EM, Schwartz C, Chang EH, Smith RJH, Stratakis CA, Weil D, Petit C, Hildebrandt F. SIX1 mutations cause branchio-oto-renal syndrome by disruption of EYA1-SIX1-DNA complexes. Proc Natl Acad Sci U S A 2004; 101:8090-5. [PMID: 15141091 PMCID: PMC419562 DOI: 10.1073/pnas.0308475101] [Citation(s) in RCA: 285] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Urinary tract malformations constitute the most frequent cause of chronic renal failure in the first two decades of life. Branchio-otic (BO) syndrome is an autosomal dominant developmental disorder characterized by hearing loss. In branchio-oto-renal (BOR) syndrome, malformations of the kidney or urinary tract are associated. Haploinsufficiency for the human gene EYA1, a homologue of the Drosophila gene eyes absent (eya), causes BOR and BO syndromes. We recently mapped a locus for BOR/BO syndrome (BOS3) to human chromosome 14q23.1. Within the 33-megabase critical genetic interval, we located the SIX1, SIX4, and SIX6 genes, which act within a genetic network of EYA and PAX genes to regulate organogenesis. These genes, therefore, represented excellent candidate genes for BOS3. By direct sequencing of exons, we identified three different SIX1 mutations in four BOR/BO kindreds, thus identifying SIX1 as a gene causing BOR and BO syndromes. To elucidate how these mutations cause disease, we analyzed the functional role of these SIX1 mutations with respect to protein-protein and protein-DNA interactions. We demonstrate that all three mutations are crucial for Eya1-Six1 interaction, and the two mutations within the homeodomain region are essential for specific Six1-DNA binding. Identification of SIX1 mutations as causing BOR/BO offers insights into the molecular basis of otic and renal developmental diseases in humans.
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Affiliation(s)
- Rainer G Ruf
- Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109, USA
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Scheinfeld NS, Silverberg NB, Weinberg JM, Nozad V. The preauricular sinus: a review of its clinical presentation, treatment, and associations. Pediatr Dermatol 2004; 21:191-6. [PMID: 15165194 DOI: 10.1111/j.0736-8046.2004.21301.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Preauricular sinuses (ear pits) are common congenital abnormalities. Usually asymptomatic, they manifest as small dells adjacent to the external ear near the anterior margin of the ascending limb of the helix, most frequently on the right side. Preauricular sinuses can be either inherited or sporadic. When inherited, they show an incomplete autosomal dominant pattern with reduced penetrance and variable expression. They may be bilateral, increasing the likelihood of being inherited, in 25-50% of cases. Preauricular sinuses are features of other conditions or syndromes in 3-10% of cases, primarily in association with deafness and branchio-oto-renal (BOR) syndrome. When other congenital anomalies coexist with these sinuses, auditory testing and renal ultrasound should be considered. Sinuses may become infected, most commonly with gram-positive bacteria, in which case their exudates should be cultured and appropriate antibiotics administered. Recurrent infection is a clear indication for complete excision and provides the only definitive cure. Recurrence rates after surgery range from 9% to 42%. Meticulous excision by an experienced head and neck surgeon minimizes the risk of recurrence.
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Affiliation(s)
- Noah S Scheinfeld
- Department of Dermatology, St. Luke's-Roosevelt Hospital Center and Beth Israel Medical Center, New York, New York, USA.
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34
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Vervoort VS, Holden KR, Ukadike KC, Collins JS, Saul RA, Srivastava AK. POMGnT1 gene alterations in a family with neurological abnormalities. Ann Neurol 2004; 56:143-8. [PMID: 15236414 DOI: 10.1002/ana.20172] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Muscle-eye-brain disease (MEB), is caused by mutations in the POMGnT1 gene. We describe a white family with two siblings affected with congenital hypotonia early-onset glaucoma, and psychomotor delays. Brain magnetic resonance images (MRIs) showed hydrocephalus, bilateral frontal polymicrogyria, abnormal cerebellum, and characteristic flattened dystrophic pons. We identified novel POMGnT1 gene alterations in this family. Both affected siblings were found to be compound hetrozygotes and carried two missense changes inherited from their mother and one missense change (p.R442C) inherited from their father. Our findings further define the phenotypic spectrum of MEB and its occurrence in the US population.
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Affiliation(s)
- Virginie S Vervoort
- J. C. Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, SC 29646, USA
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