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Masano Y, Saegusa C, Ishikawa M, Matsunaga T, Okano H, Fujioka M. Generation of an induced pluripotent stem cell line (KEIUi008-A) from a hearing loss patient with an A1555G mutation in mitochondrial DNA. Stem Cell Res 2024; 78:103452. [PMID: 38815527 DOI: 10.1016/j.scr.2024.103452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/13/2024] [Accepted: 05/24/2024] [Indexed: 06/01/2024] Open
Abstract
We report the establishment of a human induced pluripotent stem cell (iPSC) line from a 54-year-old male patient with an A1555G mutation in the mitochondrial 12S ribosomal RNA gene (MTRNR1), associated with sensorineural hearing loss. The established iPSC line expressed stemness markers or undifferentiated state markers. We also demonstrated the capacity of the cells to differentiate into the three germ layers, suggesting its pluripotency and utility in the pathological study of sensorineural hearing loss and drug screening for ear disorders.
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Affiliation(s)
- Yusuke Masano
- Department of Molecular Genetics, Kitasato University School of Medicine, Kanagawa, Japan
| | - Chika Saegusa
- Department of Molecular Genetics, Kitasato University School of Medicine, Kanagawa, Japan; Molecular Genetics Unit, Kitasato University Graduate School of Medical Science, Kanagawa, Japan; Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Mitsuru Ishikawa
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan; Division of CNS Regeneration and Drug Discovery, International Center for Brain Science, Fujita Health University, Aichi, Japan
| | - Tatsuo Matsunaga
- Division of Hearing and Balance Research, National Institute of Sensory Organs, NHO Tokyo Medical Center, Tokyo, Japan; Medical Genetics Center, NHO Tokyo Medical Center, Tokyo, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan; Division of CNS Regeneration and Drug Discovery, International Center for Brain Science, Fujita Health University, Aichi, Japan; Keio University Regenerative Medicine Research Center, Kanagawa, Japan
| | - Masato Fujioka
- Department of Molecular Genetics, Kitasato University School of Medicine, Kanagawa, Japan; Molecular Genetics Unit, Kitasato University Graduate School of Medical Science, Kanagawa, Japan; Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan; Clinical and Translational Research Center, Keio University Hospital, Tokyo, Japan
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2
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Leach M, Newman WG, McDermott JH. Rapid point of care testing: the next frontier in pharmacogenomics. Pharmacogenomics 2024; 25:289-291. [PMID: 39041736 PMCID: PMC11404691 DOI: 10.1080/14622416.2024.2366691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2024] [Accepted: 06/04/2024] [Indexed: 07/24/2024] Open
Affiliation(s)
- Marc Leach
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester, M13 9WL, UK
- Division of Evolution, Infection & Genomics, School of Biological Sciences, The University of Manchester, Manchester, M13 9PL, UK
| | - William G Newman
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester, M13 9WL, UK
- Division of Evolution, Infection & Genomics, School of Biological Sciences, The University of Manchester, Manchester, M13 9PL, UK
| | - John H McDermott
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester, M13 9WL, UK
- Division of Evolution, Infection & Genomics, School of Biological Sciences, The University of Manchester, Manchester, M13 9PL, UK
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Borisova TV, Cherdonova AM, Pshennikova VG, Teryutin FM, Morozov IV, Bondar AA, Baturina OA, Kabilov MR, Romanov GP, Solovyev AV, Fedorova SA, Barashkov NA. High prevalence of m.1555A > G in patients with hearing loss in the Baikal Lake region of Russia as a result of founder effect. Sci Rep 2024; 14:15342. [PMID: 38961196 PMCID: PMC11222474 DOI: 10.1038/s41598-024-66254-z] [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: 03/25/2024] [Accepted: 07/01/2024] [Indexed: 07/05/2024] Open
Abstract
Mitochondrial forms account approximately 1-2% of all nonsyndromic cases of hearing loss (HL). One of the most common causative variants of mtDNA is the m.1555A > G variant of the MT-RNR1 gene (OMIM 561000). Currently the detection of the m.1555A > G variant of the MT-RNR1 gene is not included in all research protocols. In this study this variant was screened among 165 patients with HL from the Republic of Buryatia, located in the Baikal Lake region of Russia. In our study, the total contribution of the m.1555A > G variant to the etiology of HL was 12.7% (21/165), while the update global prevalence of this variant is 1.8% (863/47,328). The m.1555A > G variant was notably more prevalent in Buryat (20.2%) than in Russian patients (1.3%). Mitogenome analysis in 14 unrelated Buryat families carrying the m.1555A > G variant revealed a predominant lineage: in 13 families, a cluster affiliated with sub-haplogroup A5b (92.9%) was identified, while one family had the D5a2a1 lineage (7.1%). In a Russian family with the m.1555A > G variant the lineage affiliated with sub-haplogroup F1a1d was found. Considering that more than 90% of Buryat families with the m.1555A > G variant belong to the single maternal lineage cluster we conclude that high prevalence of this variant in patients with HL in the Baikal Lake region can be attributed to a founder effect.
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Affiliation(s)
- Tuyara V Borisova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Aleksandra M Cherdonova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Vera G Pshennikova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia
| | - Fedor M Teryutin
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia
| | - Igor V Morozov
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
- Novosibirsk State University, 630090, Novosibirsk, Russia
| | - Alexander A Bondar
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
| | - Olga A Baturina
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
| | - Marsel R Kabilov
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
| | - Georgii P Romanov
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Aisen V Solovyev
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Sardana A Fedorova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia
| | - Nikolay A Barashkov
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia.
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia.
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Joo SY, Jang SH, Kim JA, Kim SJ, Kim B, Kim HY, Choi JY, Gee HY, Jung J. Prevalence and Clinical Characteristics of Mitochondrial DNA Mutations in Korean Patients With Sensorineural Hearing Loss. J Korean Med Sci 2023; 38:e355. [PMID: 38084023 PMCID: PMC10713439 DOI: 10.3346/jkms.2023.38.e355] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 09/12/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Mutations in mitochondrial DNA (mtDNA) are associated with several genetic disorders, including sensorineural hearing loss. However, the prevalence of mtDNA mutations in a large cohort of Korean patients with hearing loss has not yet been investigated. Thus, this study aimed to investigate the frequency of mtDNA mutations in a cohort of with pre- or post-lingual hearing loss of varying severity. METHODS A total of 711 Korean families involving 1,099 individuals were evaluated. Six mitochondrial variants associated with deafness (MTRNR1 m.1555A>G, MTTL1 m.3243A>G, MTCO1 m.7444G>A and m.7445A>G, and MTTS1 m.7471dupC and m.7511T>C) were screened using restriction fragment length polymorphism. The prevalence of the six variants was also analyzed in a large control dataset using whole-genome sequencing data from 4,534 Korean individuals with unknown hearing phenotype. RESULTS Overall, 12 of the 711 (1.7%) patients with hearing loss had mtDNA variants, with 10 patients from independent families positive for the MTRNR1 m.1555A>G mutation and 2 patients positive for the MTCO1 m.7444G>A mutation. The clinical characteristics of patients with the mtDNA variants were characterized by post-lingual progressive hearing loss due to the m.1555A>G variant (9 of 472; 1.9%). In addition, 18/4,534 (0.4%) of the Korean population have mitochondrial variants associated with hearing loss, predominantly the m.1555A>G variant. CONCLUSION A significant proportion of Korean patients with hearing loss is affected by the mtDNA variants, with the m.1555A>G variant being the most prevalent. These results clarify the genetic basis of hearing loss in the Korean population and emphasize the need for genetic testing for mtDNA variants.
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Affiliation(s)
- Sun Young Joo
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Korea
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea
| | - Seung Hyun Jang
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Korea
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea
| | - Jung Ah Kim
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Korea
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea
| | - Se Jin Kim
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Korea
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea
| | - Bonggi Kim
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Korea
| | - Hye-Youn Kim
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Korea
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea
| | - Jae Young Choi
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Korea
| | - Heon Yung Gee
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Korea
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea.
| | - Jinsei Jung
- Won-Sang Lee Institute for Hearing Loss, Seoul, Korea
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Korea.
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Rivetti S, Romano A, Mastrangelo S, Attinà G, Maurizi P, Ruggiero A. Aminoglycosides-Related Ototoxicity: Mechanisms, Risk Factors, and Prevention in Pediatric Patients. Pharmaceuticals (Basel) 2023; 16:1353. [PMID: 37895824 PMCID: PMC10610175 DOI: 10.3390/ph16101353] [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: 07/08/2023] [Revised: 09/17/2023] [Accepted: 09/21/2023] [Indexed: 10/29/2023] Open
Abstract
Aminoglycosides are broad-spectrum antibiotics largely used in children, but they have potential toxic side effects, including ototoxicity. Ototoxicity from aminoglycosides is permanent and is a consequence of its action on the inner ear cells via multiple mechanisms. Both uncontrollable risk factors and controllable risk factors are involved in the pathogenesis of aminoglycoside-related ototoxicity and, because of the irreversibility of ototoxicity, an important undertaking for preventing ototoxicity includes antibiotic stewardship to limit the use of aminoglycosides. Aminoglycosides are fundamental in the treatment of numerous infectious conditions at neonatal and pediatric age. In childhood, normal auditory function ensures adequate neurocognitive and social development. Hearing damage from aminoglycosides can therefore strongly affect the normal growth of the child. This review describes the molecular mechanisms of aminoglycoside-related ototoxicity and analyzes the risk factors and the potential otoprotective strategies in pediatric patients.
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Affiliation(s)
- Serena Rivetti
- Pediatric Oncology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (S.R.); (A.R.); (S.M.); (G.A.); (P.M.)
| | - Alberto Romano
- Pediatric Oncology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (S.R.); (A.R.); (S.M.); (G.A.); (P.M.)
| | - Stefano Mastrangelo
- Pediatric Oncology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (S.R.); (A.R.); (S.M.); (G.A.); (P.M.)
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Giorgio Attinà
- Pediatric Oncology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (S.R.); (A.R.); (S.M.); (G.A.); (P.M.)
| | - Palma Maurizi
- Pediatric Oncology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (S.R.); (A.R.); (S.M.); (G.A.); (P.M.)
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Antonio Ruggiero
- Pediatric Oncology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (S.R.); (A.R.); (S.M.); (G.A.); (P.M.)
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
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Lopes J, Vidal-Folch N, Lundquist P, Schimmenti LA, Demirel N, Dean V, Olson J, Auth T, Butz M, Reed K, Wylam M, Balcom J, Boczek NJ, Hasadsri L. Aminoglycoside induced ototoxicity risk in the cystic fibrosis population: The utility of large-scale screening. Pediatr Pulmonol 2023; 58:819-824. [PMID: 36437230 DOI: 10.1002/ppul.26259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 10/24/2022] [Accepted: 11/25/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND MT-RNR1 variants are a well-known cause of aminoglycoside-induced hearing loss (AIHL). Individuals with cystic fibrosis (CF) routinely receive aminoglycosides and are at high risk of AIHL. However, genetic testing before treatment is not routinely performed due to perceived rarity of risk, and cost ineffectiveness with traditional technologies. AIM Assess the utility of large-scale screening for AIHL risk in the CF population, using digital droplet polymerase chain reaction (ddPCR), a novel and scalable low-cost molecular technique. METHODS Using a clinically validated ddPCR assay, we performed retrospective testing on 122 and prospective testing on 32 individuals with CF for the two most common pathogenic variants associated with AIHL, MT-RNR1 m.1555 A > G and m.1494 C > T. Our study screened the largest known cohort of pediatric cases of CF (94/154) for these specific alterations. RESULTS We identified two individuals positive for MT-RNR1 m.1555 A > G and no positives for m.1494 C > T. Of 32 prospective cases, 17 had aminoglycoside exposure. The positive case in our prospective group recently began inhaled tobramycin and denied hearing issues. The clinician adjusted to care for both the patient and sibling with CF (not included in cohort) who is presumed positive for m.1555 A > G due to the nature of mitochondrial inheritance. CONCLUSION Our findings demonstrate the utility of pretreatment screening in the cystic fibrosis population for AIHL risk using ddPCR, a scalable and robust testing methodology at a fraction of the cost as compared to other sequencing-based methods. Therefore, the use of large-scale screening for AIHL risk in the cystic fibrosis community should be re-visited.
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Affiliation(s)
- Jaime Lopes
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Noemi Vidal-Folch
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Patrick Lundquist
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Lisa A Schimmenti
- Department of Clinical Genomics, Mayo Clinic, Rochester, Minnesota, USA
| | - Nadir Demirel
- Department of Pediatrics, Mayo Clinic, Rochester, Minnesota, USA
| | - Vicki Dean
- Department of Pediatrics, Mayo Clinic, Rochester, Minnesota, USA
| | - Janelle Olson
- Department of Pediatrics, Mayo Clinic, Rochester, Minnesota, USA
| | - Tom Auth
- Department of Research Services, Mayo Clinic, Rochester, Minnesota, USA
| | - Malinda Butz
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Katelyn Reed
- Department of Research Services, Mayo Clinic, Rochester, Minnesota, USA
| | - Mark Wylam
- Division of Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Jessica Balcom
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Nicole J Boczek
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Linda Hasadsri
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
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Huang Q, Liu Y, Lei W, Liang J, Wang Y, Zheng M, Huang X, Liu Y, Huang K, Huang M. Detecting mitochondrial mutations associated with aminoglycoside ototoxicity by noninvasive prenatal testing. J Clin Lab Anal 2022; 37:e24827. [PMID: 36579624 PMCID: PMC9833975 DOI: 10.1002/jcla.24827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 12/11/2022] [Accepted: 12/18/2022] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVES Numerous diseases and disorders are associated with mitochondrial DNA (mtDNA) mutations, among which m.1555A > G and m.1494C > T mutations in the 12 S ribosomal RNA gene contribute to aminoglycoside-induced and nonsyndromic hearing loss worldwide. METHODS A total of 76,842 qualified non-invasive prenatal (NIPT) samples were subjected to mtDNA mutation and haplogroup analysis. RESULTS We detected 181 m.1555A > G and m.1494C > T mutations, 151 of which were subsequently sequenced for full-length mitochondrial genome verification. The positive predictive values for the m.1555A > G and m.1494C > T mutations were 90.78% and 90.00%, respectively, a performance comparable to that attained with newborn hearing screening. Furthermore, mitochondrial haplogroup analysis revealed that the 12 S rRNA 1555A > G mutation was enriched in sub-haplotype D5[p = 0, OR = 4.6706(2.81-7.78)]. CONCLUSIONS Our findings indicate that the non-invasive prenatal testing of cell-free DNA obtained from maternal plasma can successfully detect m.1555A > G and m.1494C > T mutations.
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Affiliation(s)
- Quanfei Huang
- Institute of Clinical Pharmacology, School of Pharmaceutical SciencesSun Yat‐Sen UniversityGuangzhouChina
| | - Yanhui Liu
- Dongguan Maternal and Child Health HospitalDongguanChina,Dongguan maternal and Child Health Hospital Affiliated to Southern Medical UniversityDongguanChina
| | - Wei Lei
- CapitalBio Genomics Co., Ltd.DongguanChina,CapitalBio Technology Co., Ltd.BeijingChina
| | - Jiajie Liang
- Dongguan Maternal and Child Health HospitalDongguanChina,Dongguan maternal and Child Health Hospital Affiliated to Southern Medical UniversityDongguanChina
| | - Yang Wang
- CapitalBio Genomics Co., Ltd.DongguanChina,CapitalBio Technology Co., Ltd.BeijingChina
| | - Minhua Zheng
- Dongguan Maternal and Child Health HospitalDongguanChina,Dongguan maternal and Child Health Hospital Affiliated to Southern Medical UniversityDongguanChina
| | - Xiaoyan Huang
- CapitalBio Genomics Co., Ltd.DongguanChina,CapitalBio Technology Co., Ltd.BeijingChina
| | - Yuanru Liu
- CapitalBio Technology Co., Ltd.BeijingChina,Guangdong CapitalBio Medical LaboratoryDongguanChina
| | - Kaisheng Huang
- CapitalBio Technology Co., Ltd.BeijingChina,Guangdong CapitalBio Medical LaboratoryDongguanChina
| | - Min Huang
- Institute of Clinical Pharmacology, School of Pharmaceutical SciencesSun Yat‐Sen UniversityGuangzhouChina
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Lysakowski A, Govindaraju AC, Raphael RM. Structural and functional diversity of mitochondria in vestibular/cochlear hair cells and vestibular calyx afferents. Hear Res 2022; 426:108612. [PMID: 36223702 DOI: 10.1016/j.heares.2022.108612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 07/21/2022] [Accepted: 09/19/2022] [Indexed: 11/30/2022]
Abstract
Mitochondria supply energy in the form of ATP to drive a plethora of cellular processes. In heart and liver cells, mitochondria occupy over 20% of the cellular volume and the major need for ATP is easily identifiable - i.e., to drive cross-bridge recycling in cardiac cells or biosynthetic machinery in liver cells. In vestibular and cochlear hair cells the overall cellular mitochondrial volume is much less, and mitochondria structure varies dramatically in different regions of the cell. The regional demands for ATP and cellular forces that govern mitochondrial structure and localization are not well understood. Below we review our current understanding of the heterogeneity of form and function in hair cell mitochondria. A particular focus of this review will be on regional specialization in vestibular hair cells, where large mitochondria are found beneath the cuticular plate in close association with the striated organelle. Recent findings on the role of mitochondria in hair cell death and aging are covered along with potential therapeutic approaches. Potential avenues for future research are discussed, including the need for integrated computational modeling of mitochondrial function in hair cells and the vestibular afferent calyx.
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Affiliation(s)
- Anna Lysakowski
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St., M/C 512, Chicago, IL 60605, USA.
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Huang X, Wu D, Zhu L, Wang W, Yang R, Yang J, He Q, Zhu B, You Y, Xiao R, Zhao Z. Application of a next-generation sequencing (NGS) panel in newborn screening efficiently identifies inborn disorders of neonates. Orphanet J Rare Dis 2022; 17:66. [PMID: 35193651 PMCID: PMC8862216 DOI: 10.1186/s13023-022-02231-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 02/06/2022] [Indexed: 11/10/2022] Open
Abstract
Background Newborn screening (NBS) has been implemented for neonatal inborn disorders using various technology platforms, but false-positive and false-negative results are still common. In addition, target diseases of NBS are limited by suitable biomarkers. Here we sought to assess the feasibility of further improving the screening using next-generation sequencing technology. Methods We designed a newborn genetic sequencing (NBGS) panel based on multiplex PCR and next generation sequencing to analyze 134 genes of 74 inborn disorders, that were validated in 287 samples with previously known mutations. A retrospective cohort of 4986 newborns was analyzed and compared with the biochemical results to evaluate the performance of this panel. Results The accuracy of the panel was 99.65% with all samples, and 154 mutations from 287 samples were 100% detected. In 4986 newborns, a total of 113 newborns were detected with biallelic or hemizygous mutations, of which 36 newborns were positive for the same disorder by both NBGS and conventional NBS (C-NBS) and 77 individuals were NBGS positive/C-NBS negative. Importantly, 4 of the 77 newborns were diagnosed currently including 1 newborn with methylmalonic acidemia, 1 newborn with primary systemic carnitine deficiency and 2 newborns with Wilson’s disease. A total of 1326 newborns were found to be carriers with an overall carrier rate of 26.6%. Conclusion Analysis based on next generation sequencing could effectively identify neonates affected with more congenital disorders. Combined with C-NBS, this approach may improve the early and accurate identification of neonates with inborn disorders. Our study lays the foundation for prospective studies and for implementing NGS-based analysis in NBS. Supplementary Information The online version contains supplementary material available at 10.1186/s13023-022-02231-x.
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Affiliation(s)
- Xinwen Huang
- Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, People's Republic of China
| | - Dingwen Wu
- Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, People's Republic of China.,Zhejiang Neonatal Screening Center, Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Lin Zhu
- Hangzhou Biosan Clinical Laboratory Co. Ltd, 859 Shixiang West Road, Hangzhou, Zhejiang Province, People's Republic of China
| | - Wenjun Wang
- Hangzhou Biosan Clinical Laboratory Co. Ltd, 859 Shixiang West Road, Hangzhou, Zhejiang Province, People's Republic of China
| | - Rulai Yang
- Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, People's Republic of China
| | - Jianbin Yang
- Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, People's Republic of China
| | - Qunyan He
- Zhejiang Biosan Biochemical Technologies Co. Ltd, 859 Shixiang West Rd, Hangzhou, 310007, Zhejiang Province, People's Republic of China
| | - Bingquan Zhu
- Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, People's Republic of China.,Department of Child Healthcare, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, People's Republic of China
| | - Ying You
- Zhejiang Biosan Biochemical Technologies Co. Ltd, 859 Shixiang West Rd, Hangzhou, 310007, Zhejiang Province, People's Republic of China
| | - Rui Xiao
- Zhejiang Biosan Biochemical Technologies Co. Ltd, 859 Shixiang West Rd, Hangzhou, 310007, Zhejiang Province, People's Republic of China.
| | - Zhengyan Zhao
- Department of Genetics and Metabolism, Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, People's Republic of China. .,Department of PediatricsChildren's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, 3333 Binsheng Rd, Hangzhou, 310052, Zhejiang Province, People's Republic of China.
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10
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McDermott JH, Wolf J, Hoshitsuki K, Huddart R, Caudle KE, Whirl-Carrillo M, Steyger PS, Smith RJH, Cody N, Rodriguez-Antona C, Klein TE, Newman WG. Clinical Pharmacogenetics Implementation Consortium Guideline for the Use of Aminoglycosides Based on MT-RNR1 Genotype. Clin Pharmacol Ther 2022; 111:366-372. [PMID: 34032273 PMCID: PMC8613315 DOI: 10.1002/cpt.2309] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/17/2021] [Indexed: 02/03/2023]
Abstract
Aminoglycosides are widely used antibiotics with notable side effects, such as nephrotoxicity, vestibulotoxicity, and sensorineural hearing loss (cochleotoxicity). MT-RNR1 is a gene that encodes the 12s rRNA subunit and is the mitochondrial homologue of the prokaryotic 16s rRNA. Some MT-RNR1 variants (i.e., m.1095T>C; m.1494C>T; m.1555A>G) more closely resemble the bacterial 16s rRNA subunit and result in increased risk of aminoglycoside-induced hearing loss. Use of aminoglycosides should be avoided in individuals with an MT-RNR1 variant associated with an increased risk of aminoglycoside-induced hearing loss unless the high risk of permanent hearing loss is outweighed by the severity of infection and safe or effective alternative therapies are not available. We summarize evidence from the literature supporting this association and provide therapeutic recommendations for the use of aminoglycosides based on MT-RNR1 genotype (updates at https://cpicpgx.org/guidelines/ and www.pharmgkb.org).
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Affiliation(s)
- John Henry McDermott
- Manchester Centre for Genomic Medicine, St. Mary’s Hospital, Manchester University NHS Foundation Trust, Manchester, UK
- Division of Evolution and Genomic Sciences, School of Biological Sciences, University of Manchester, Manchester, UK
| | - Joshua Wolf
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Keito Hoshitsuki
- School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Rachel Huddart
- Department of Biomedical Data Science, Stanford University, Stanford, California, USA
| | - Kelly E. Caudle
- Department of Pharmaceutical Sciences, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | | | - Peter S. Steyger
- Translational Hearing Center, Biomedical Sciences, Creighton University, National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, Oregon, USA
| | - Richard J. H. Smith
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Internal Medicine (Nephrology), Pediatrics and Molecular Physiology & Biophysics, University of Iowa, Iowa City, Iowa, USA
| | - Neal Cody
- Department of Genetics and Genomic Sciences, Ichan School of Medicine at Mount Sinai, New York, New York, USA
- Sema4, Stamford, Connecticut, USA
| | - Cristina Rodriguez-Antona
- Hereditary Endocrine Cancer Group, Human Cancer Genetics Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Teri E. Klein
- Department of Biomedical Data Science, Stanford University, Stanford, California, USA
- Department of Medicine, Stanford University, Stanford, California, USA
| | - William G. Newman
- Manchester Centre for Genomic Medicine, St. Mary’s Hospital, Manchester University NHS Foundation Trust, Manchester, UK
- Division of Evolution and Genomic Sciences, School of Biological Sciences, University of Manchester, Manchester, UK
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11
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Phenotype-genotype correlation in patients with typical and atypical branchio-oto-renal syndrome. Sci Rep 2022; 12:969. [PMID: 35046468 PMCID: PMC8770796 DOI: 10.1038/s41598-022-04885-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 12/29/2021] [Indexed: 12/31/2022] Open
Abstract
Some patients have an atypical form of branchio-oto-renal (BOR) syndrome, which does not satisfy the diagnostic criteria, despite carrying a pathogenic variant (P variant) or a likely pathogenic variant (LP variant) of a causative gene. P/LP variants phenotypic indices have yet to be determined in patients with typical and atypical BOR syndrome. We hypothesized that determining phenotypic and genetic differences between patients with typical and atypical BOR syndrome could inform such indices. Subjects were selected from among patients who underwent genetic testing to identify the cause of hearing loss. Patients were considered atypical when they had two major BOR diagnostic criteria, or two major criteria and one minor criterion; 22 typical and 16 atypical patients from 35 families were included. Genetic analysis of EYA1, SIX1, and SIX5 was conducted by direct sequencing and multiplex ligation-dependent probe amplification. EYA1 P/LP variants were detected in 25% and 86% of atypical and typical patients, respectively. Four EYA1 P/LP variants were novel. Branchial anomaly, inner ear anomaly, and mixed hearing loss were correlated with P/LP variants. Development of refined diagnostic criteria and phenotypic indices for atypical BOR syndrome will assist in effective detection of patients with P/LP variants among those with suspected BOR syndrome.
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12
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Li S, Gai X, Myint SS, Arroyo K, Morimoto L, Metayer C, de Smith AJ, Walsh KM, Wiemels JL. Mitochondrial 1555 G>A variant as a potential risk factor for childhood glioblastoma. Neurooncol Adv 2022; 4:vdac045. [PMID: 35571988 PMCID: PMC9092641 DOI: 10.1093/noajnl/vdac045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Background Childhood glioblastoma multiforme (GBM) is a highly aggressive disease with low survival, and its etiology, especially concerning germline genetic risk, is poorly understood. Mitochondria play a key role in putative tumorigenic processes relating to cellular oxidative metabolism, and mitochondrial DNA variants were not previously assessed for association with pediatric brain tumor risk. Methods We conducted an analysis of 675 mitochondrial DNA variants in 90 childhood GBM cases and 2789 controls to identify enrichment of mitochondrial variant associated with GBM risk. We also performed this analysis for other glioma subtypes including pilocytic astrocytoma. Nuclear-encoded mitochondrial gene variants were also analyzed. Results We identified m1555 A>G was significantly associated with GBM risk (adjusted OR 29.30, 95% CI 5.25-163.4, P-value 9.5 X 10-4). No association was detected for other subtypes. Haplotype analysis further supported the independent risk contributed by m1555 G>A, instead of a haplogroup joint effect. Nuclear-encoded mitochondrial gene variants identified significant associations in European (rs62036057 in WWOX, adjusted OR = 2.99, 95% CI 1.88-4.75, P-value = 3.42 X 10-6) and Hispanic (rs111709726 in EFHD1, adjusted OR = 3.57, 95% CI 1.99-6.40, P-value = 1.41 X 10-6) populations in ethnicity-stratified analyses. Conclusion We report for the first time a potential role played by a functional mitochondrial ribosomal RNA variant in childhood GBM risk, and a potential role for both mitochondrial and nuclear-mitochondrial DNA polymorphisms in GBM tumorigenesis. These data implicate cellular oxidative metabolic capacity as a contributor to the etiology of pediatric glioblastoma.
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Affiliation(s)
- Shaobo Li
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, USA
| | - Xiaowu Gai
- Center for Personalized Medicine, Children’s Hospital of Los Angeles, Los Angeles, California, USA
| | - Swe Swe Myint
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, USA
| | - Katti Arroyo
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, USA
| | - Libby Morimoto
- School of Public Health, University of California Berkeley, Berkeley, California, USA
| | - Catherine Metayer
- School of Public Health, University of California Berkeley, Berkeley, California, USA
| | - Adam J de Smith
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, USA
| | - Kyle M Walsh
- Division of Neuro-epidemiology, Department of Neurosurgery, Duke University, Durham, North Carolina, USA
| | - Joseph L Wiemels
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, University of Southern California, Los Angeles, California, USA
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13
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Dai Q, Dai W, Wang D, Liu X, Zou L, Chen J, Zheng H, Duan M. Molecular screening of patients with profound hearing loss from Chengdu, China. Acta Otolaryngol 2022; 142:57-60. [PMID: 34936523 DOI: 10.1080/00016489.2021.2014564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND The rate of genetic deafness in Chengdu is still underestimated. OBJECTIVE To investigate patients' molecular etiology with profound hearing loss and facilitate genetic counseling for their families, we screened deafness-related genes of profound hearing loss in the population. METHODS A total of 1427 unrelated patients with profound hearing loss containing all age groups in the administrative area of City Chengdu (Sichuan, China) were enrolled in this study, and the average examination rate is 81.13%. Nine loci of four deaf-associated genes (GJB2, GJB3, SLC26A4, and mitochondrial 12SrRNA gene) were analyzed. Then we examined all the deaf-associated mutations and compared them between groups. RESULTS The average age of all subjects is 48.537 ± 19.077 years, peak range in 41-70 years (985/1427, 69.03%). The positive mutation rates of patients in GJB2, SLC26A4, and 12S rRNA are respectively 8.90%, 4.84%, and 5.96%, and GJB3 none. In group A the GJB2 and SLC26A4 mutation rate is 14.17% (36/254), which is remarkably higher than group B (6.14%, 72/1173). The frequency of 12SrRNA mutations is 3.15% (8/254) in group A, which is significantly different (χ2 = 4.34, p < .05) from that of group B (6.56%, 77/1173). CONCLUSIONS AND SIGNIFICANCE The mutation rate of mtDNA 12SrRNA is higher than SLC26A4 gene in our study, which is different from other parts of China. And the deaf-related gene mutation spectrums have a distinct age difference.
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Affiliation(s)
- Qingqing Dai
- Department of Otolaryngology, West China Hospital, Sichuan University, Chengdu, China
- Department of Otolaryngology Head and Neck & Audiology and Neurotology, Department of Clinical Science, Intervention and Technology, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden
| | - Wei Dai
- Department of Otolaryngology, West China Hospital, Sichuan University, Chengdu, China
| | - Dan Wang
- Department of Otolaryngology, West China Hospital, Sichuan University, Chengdu, China
| | - Xia Liu
- Sichuan Hearing and Language Rehabilitation Center, Chengdu, China
| | - Ling Zou
- Chengdu Women’s and Children’s Central Hospital, Chengdu, China
| | - Jiani Chen
- Department of Otolaryngology, West China Hospital, Sichuan University, Chengdu, China
| | - Hong Zheng
- Department of Otolaryngology, West China Hospital, Sichuan University, Chengdu, China
| | - Maoli Duan
- Department of Otolaryngology Head and Neck & Audiology and Neurotology, Department of Clinical Science, Intervention and Technology, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden
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14
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Investigating the importance of individual mitochondrial genotype in susceptibility to drug-induced toxicity. Biochem Soc Trans 2021; 48:787-797. [PMID: 32453388 PMCID: PMC7329340 DOI: 10.1042/bst20190233] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 12/13/2022]
Abstract
The mitochondrion is an essential organelle responsible for generating cellular energy. Additionally, mitochondria are a source of inter-individual variation as they contain their own genome. Evidence has revealed that mitochondrial DNA (mtDNA) variation can confer differences in mitochondrial function and importantly, these differences may be a factor underlying the idiosyncrasies associated with unpredictable drug-induced toxicities. Thus far, preclinical and clinical data are limited but have revealed evidence in support of an association between mitochondrial haplogroup and susceptibility to specific adverse drug reactions. In particular, clinical studies have reported associations between mitochondrial haplogroup and antiretroviral therapy, chemotherapy and antibiotic-induced toxicity, although study limitations and conflicting findings mean that the importance of mtDNA variation to toxicity remains unclear. Several studies have used transmitochondrial cybrid cells as personalised models with which to study the impact of mitochondrial genetic variation. Cybrids allow the effects of mtDNA to be assessed against a stable nuclear background and thus the in vitro elucidation of the fundamental mechanistic basis of such differences. Overall, the current evidence supports the tenet that mitochondrial genetics represent an exciting area within the field of personalised medicine and drug toxicity. However, further research effort is required to confirm its importance. In particular, efforts should focus upon translational research to connect preclinical and clinical data that can inform whether mitochondrial genetics can be useful to identify at risk individuals or inform risk assessment during drug development.
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15
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Isaka Y, Nishio SY, Hishinuma E, Hiratsuka M, Usami SI. Improvement of a Rapid and Highly Sensitive Method for the Diagnosis of the Mitochondrial m.1555A>G Mutation Based on a Single-Stranded Tag Hybridization Chromatographic Printed-Array Strip. Genet Test Mol Biomarkers 2021; 25:79-83. [PMID: 33372830 PMCID: PMC7821431 DOI: 10.1089/gtmb.2020.0105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Aims: Pathogenic variants in mitochondrial DNA are known to be associated with sensorineural hearing loss (SNHL) and aminoglycoside-induced HL. Among them, the m.1555A>G mutation is the most common. Thus, a rapid and easy companion diagnostic method for this mutation would be desirable to prevent HL caused by aminoglycoside therapy. In this study, we report an improved protocol for the single-stranded tag hybridization chromatographic printed-array strip (STH-PAS) method for identifying the m.1555A>G mutation. Methods: To evaluate the accuracy of a novel diagnostic for the m.1555A>G mutation we analyzed 378 DNA samples with or without the m.1555A>G mutation, as determined by Invader assay, and calculated the sensitivity, specificity, and false negative and false positive ratios of this new method. Results: The newly developed protocol was robust; we, obtained the same results using multiple DNA concentrations, differing annealing temperatures, and different polymerase chain reaction thermal cyclers. The diagnostic sensitivity based on the STH-PAS method was 0.99, and the specificity was 1.00. The false negative and false positive ratios were 0 and 0.01, respectively. Conclusion: We improved the genotyping method for m.1555A>G mutations. This assays will be useful as a rapid companion diagnostic before aminoglycoside use.
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Affiliation(s)
- Yuichi Isaka
- Department of Hearing Implant Sciences and Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-ya Nishio
- Department of Hearing Implant Sciences and Shinshu University School of Medicine, Matsumoto, Japan
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Eiji Hishinuma
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
- Advanced Research Center for Innovations in Next-Generation Medicine and Tohoku University, Sendai, Japan
- Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Masahiro Hiratsuka
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
- Advanced Research Center for Innovations in Next-Generation Medicine and Tohoku University, Sendai, Japan
- Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Shin-ichi Usami
- Department of Hearing Implant Sciences and Shinshu University School of Medicine, Matsumoto, Japan
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
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16
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The use of a MITO-Porter to deliver exogenous therapeutic RNA to a mitochondrial disease's cell with a A1555G mutation in the mitochondrial 12S rRNA gene results in an increase in mitochondrial respiratory activity. Mitochondrion 2020; 55:134-144. [PMID: 33035688 DOI: 10.1016/j.mito.2020.09.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 09/01/2020] [Accepted: 09/28/2020] [Indexed: 01/02/2023]
Abstract
We report on validating a mitochondrial gene therapeutic strategy using fibroblasts derived from patients with an A1555G point mutation in mitochondrial DNA coding 12S ribosomal RNA (rRNA (12S)). Wild-type rRNA (12S) as a therapeutic RNA was encapsulated in a mitochondrial targeting liposome, a MITO-Porter (rRNA-MITO-Porter), and an attempt was made to deliver the MITO-Porter to mitochondria of the diseased cells. It was confirmed that the rRNA-MITO-Porter treatment significantly decreased the ratio of the mutant rRNA content. Moreover, it was shown that the mitochondrial respiratory activities of the diseased cells were improved as the result of the mitochondrial transfection of the rRNA-MITO-Porter.
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17
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Maeda Y, Sasaki A, Kasai S, Goto S, Nishio SY, Sawada K, Tokuda I, Itoh K, Usami SI, Matsubara A. Prevalence of the mitochondrial 1555 A>G and 1494 C>T mutations in a community-dwelling population in Japan. Hum Genome Var 2020; 7:27. [PMID: 33014404 PMCID: PMC7501278 DOI: 10.1038/s41439-020-00115-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/07/2020] [Accepted: 08/13/2020] [Indexed: 02/04/2023] Open
Abstract
Single nucleotide polymorphisms in mitochondrial DNA, such as mitochondrial 1555 A>G (m.1555 A>G) and mitochondrial 1494 C>T (m.1494 C>T), are known to be causative mutations of nonsyndromic hearing loss following exposure to aminoglycoside antibiotics. The prevalence of the m.1555 A>G and m.1494 C>T mutations has not been reported for the general population in Japan. The purpose of this study was to investigate the prevalence of m.1555 A>G and m.1494 C>T mutations in a community-dwelling population in Japan in order to prevent aminoglycoside-induced hearing loss. We recruited participants older than 20 years of age to the Iwaki Health Promotion Project in 2014, 2015, and 2016, resulting in the recruitment of 1,683 participants. For each participant, we performed a hearing test and a genetic test for the m.1555 A>G and m.1494 C>T mutations using the TaqMan genotyping method. The m.1555 A>G mutation was detected in only 1 of the 1,683 participants (0.06%). This carrier of the m.1555 A>G mutation was a 69-year-old male with bilateral, symmetric, and high-frequency hearing loss. We provided genetic counseling and distributed a drug card advising him to avoid the administration of aminoglycoside antibiotics. In contrast, the m.1494 C>T mutation was not detected in this study population.
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Affiliation(s)
- Yasunori Maeda
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Akira Sasaki
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shuya Kasai
- Department of Stress Response Science, Center for Advanced Medical Research, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shinichi Goto
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Kaori Sawada
- Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan
| | - Itoyo Tokuda
- Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan
| | - Ken Itoh
- Department of Stress Response Science, Center for Advanced Medical Research, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Atsushi Matsubara
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
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Zheng J, Bai X, Xiao Y, Ji Y, Meng F, Aishanjiang M, Gao Y, Wang H, Fu Y, Guan MX. Mitochondrial tRNA mutations in 887 Chinese subjects with hearing loss. Mitochondrion 2020; 52:163-172. [PMID: 32169613 DOI: 10.1016/j.mito.2020.03.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/13/2020] [Accepted: 03/09/2020] [Indexed: 01/24/2023]
Abstract
Mutations in the mitochondrial tRNAs have been reported to be the important cause of hearing loss. However, only a few cases have been identified thus far and the prevalence of mitochondrial tRNA mutations in hearing-impaired patients remain unclear. Here we performed the mutational analysis of 22 mitochondrial tRNA genes in a large cohort of 887 Han Chinese subjects with hearing loss by Sanger sequencing. The systemic evaluation of putative pathogenic variants was further carried out by frequency in controls (<1%), phylogenetic analysis, structural analysisandfunctionalprediction. As a result, a total of 147 variants on 22 tRNA genes were identified. Among these, 39 tRNA mutations (10 pathogenic and 29 likely pathogenic) which absent or present <1% in 773 Chinese controls, localized at highly conserved nucleotides, or changed the modified nucleotides, could have potential structural alterations and functional significance, thereby considered to be deafness-associated mutations. Furthermore, 44 subjects carried one of these 39 pathogenic/likely pathogenic tRNA mutations with a total prevalence of 4.96%. However, the phenotypic variability and incomplete penetrance of hearing loss in pedigrees carrying these tRNA mutations indicate the involvement of modifier factors, such as nuclear encoded genes associated with mitochondrion biogenesis, mitochondrial haplotypes, epigenetic and environmental factors. Thus, our data provide the evidence that mitochondrial tRNA mutations are the important causes of hearing loss among Chinese population. These findings further increase our knowledge on the clinical relevance of tRNA mutations in the mitochondrial genome, and should be helpful to elucidate the pathogenesis of maternal hearing loss.
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Affiliation(s)
- Jing Zheng
- Division of Medical Genetics and Genomics, and Department of Genetic and Metabolic Diseases, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Xiaohui Bai
- Department of Otorhinolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong 250022, China
| | - Yun Xiao
- Division of Medical Genetics and Genomics, and Department of Genetic and Metabolic Diseases, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China; Department of Otorhinolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong 250022, China
| | - Yanchun Ji
- Division of Medical Genetics and Genomics, and Department of Genetic and Metabolic Diseases, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Feilong Meng
- Division of Medical Genetics and Genomics, and Department of Genetic and Metabolic Diseases, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Maerhaba Aishanjiang
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Yinglong Gao
- Division of Medical Genetics and Genomics, and Department of Genetic and Metabolic Diseases, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Haibo Wang
- Department of Otorhinolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong 250022, China.
| | - Yong Fu
- Division of Medical Genetics and Genomics, and Department of Genetic and Metabolic Diseases, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China; Department of Otorhinolaryngology Head and Neck Surgery, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China.
| | - Min-Xin Guan
- Division of Medical Genetics and Genomics, and Department of Genetic and Metabolic Diseases, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
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Favrelière S, Delaunay P, Lebreton JP, Rouby F, Atzenhoffer M, Lafay-Chebassier C, Pérault-Pochat MC. Drug-induced hearing loss: a case/non-case study in the French pharmacovigilance database. Fundam Clin Pharmacol 2020; 34:397-407. [PMID: 31912913 DOI: 10.1111/fcp.12533] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 12/06/2019] [Accepted: 01/06/2020] [Indexed: 11/29/2022]
Abstract
Hearing loss is defined as a decrease in the ability to perceive sounds which can occur suddenly or gradually and affects one ear or both. It is related to various etiologies, in particular drugs. The identification of all drugs that could be associated with hearing loss is essential for the patients' life quality. The objective of our study was to identify signals of hearing loss involving drugs approved in the last 20 years. The occurrence in association with drugs known for their ototoxicity was also analyzed. We used a case/non-case method in the French Pharmacovigilance Database (FPVD). The cases were reports of hearing loss in the FPVD between January 2007 and August 2017. Non-cases were all reports over the same period. We calculated the reporting odds ratio (ROR) with 95% confidence intervals. Among the 555 reports of hearing loss, significant RORs were found for 68 drugs. The main therapeutic classes implicated were antineoplastic agents (n = 240), systemic anti-infective agents (n = 182), immunosuppressants (n = 42) loop diuretics (n = 26), and salicylate analgesics (n = 26). We found signals of hearing loss with azacitidine, vaccines and nevirapine, immunosuppressants such as leflunomide, and biotherapies such as panitumumab and vandetanib. Prescribers should be informed about the potential associations with all these drugs. The role of the pathology itself and the known ototoxic drugs that can be associated do not allow to conclude definitively. Audiograms for the early detection of hearing loss induced by drugs known to be ototoxic are rarely carried out. Preventive treatments exist and must be considered.
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Affiliation(s)
- Sylvie Favrelière
- Department of Clinical Pharmacology and Pharmacovigilance, University Hospital of Poitiers, 2 rue de la Milètrie, BP 577, 86021, Poitiers Cedex, France
| | - Paul Delaunay
- Department of Clinical Pharmacology and Pharmacovigilance, University Hospital of Poitiers, 2 rue de la Milètrie, BP 577, 86021, Poitiers Cedex, France
| | - Jean-Pascal Lebreton
- Department of Otorhinolaryngology - Head & Neck Surgery, University Hospital of Poitiers, 2, rue de la Milètrie, BP 577, 86021, Poitiers Cedex, France
| | - Franck Rouby
- Department of Clinical Pharmacology and Pharmacovigilance, University Hospital of Marseille, 270 Boulevard Sainte Marguerite, 13009, Marseille, France
| | - Martine Atzenhoffer
- Department of Clinical Pharmacology and Pharmacovigilance, Hospices civils de Lyon, 69424, Lyon, France
| | - Claire Lafay-Chebassier
- Department of Clinical Pharmacology and Pharmacovigilance, University Hospital of Poitiers, 2 rue de la Milètrie, BP 577, 86021, Poitiers Cedex, France.,INSERM, U1084, Laboratoire de Neurosciences Expérimentales et Cliniques - LNEC, Université de Poitiers, Batiment B36, 1 rue Georges Bonnet, BP633, 86022, Poitiers Cedex, France
| | - Marie Christine Pérault-Pochat
- Department of Clinical Pharmacology and Pharmacovigilance, University Hospital of Poitiers, 2 rue de la Milètrie, BP 577, 86021, Poitiers Cedex, France.,INSERM, U1084, Laboratoire de Neurosciences Expérimentales et Cliniques - LNEC, Université de Poitiers, Batiment B36, 1 rue Georges Bonnet, BP633, 86022, Poitiers Cedex, France
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Usami SI, Nishio SY, Moteki H, Miyagawa M, Yoshimura H. Cochlear Implantation From the Perspective of Genetic Background. Anat Rec (Hoboken) 2020; 303:563-593. [PMID: 32027099 PMCID: PMC7064903 DOI: 10.1002/ar.24360] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 12/13/2019] [Indexed: 12/18/2022]
Abstract
While cochlear implantation (CI) technology has greatly improved over the past 40 years, one aspect of CI that continues to pose difficulties is the variability of outcomes due to numerous factors involved in postimplantation performance. The electric acoustic stimulation (EAS) system has expanded indications for CI to include patients with residual hearing, and is currently becoming a standard therapy for these patients. Genetic disorders are known to be the most common cause of congenital/early-onset sensorineural hearing loss, and are also involved in a considerable proportion of cases of late-onset hearing loss. There has been a great deal of progress in the identification of deafness genes over the last two decades. Currently, more than 100 genes have been reported to be associated with non-syndromic hearing loss. Patients possessing a variety of deafness gene mutations have achieved satisfactory auditory performance after CI/EAS, suggesting that identification of the genetic background facilitates prediction of post-CI/EAS performance. When the intra-cochlear etiology is associated with a specific genetic background, there is a potential for good CI performance. Thus, it is essential to determine which region of the cochlea is affected by identifying the responsible genes. This review summarizes the genetic background of the patients receiving CI/EAS, and introduces detailed clinical data and CI/EAS outcomes in representative examples. Anat Rec, 303:563-593, 2020. © 2020 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Hideaki Moteki
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Maiko Miyagawa
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Hidekane Yoshimura
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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21
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Xiang YB, Tang SH, Li HZ, Xu CY, Chen C, Xu YZ, Ding LR, Xu XQ. Mutation analysis of common deafness-causing genes among 506 patients with nonsyndromic hearing loss from Wenzhou city, China. Int J Pediatr Otorhinolaryngol 2019; 122:185-190. [PMID: 31035178 DOI: 10.1016/j.ijporl.2019.04.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/16/2019] [Accepted: 04/16/2019] [Indexed: 12/17/2022]
Abstract
OBJECTIVES The frequency and spectrum of mutations in deafness-causing genes differs significantly according to the ethnic population and region under investigation. The molecular etiology of nonsyndromic hearing loss (NSHL) in Wenzhou, China, has not yet been systematically elucidated. To provide accurate genetic testing and counseling in this area, we investigated the molecular etiology of NSHL in a deaf population from Wenzhou. METHODS A total 506 unrelated patients with NSHL were enrolled in this study. Nine hotspot mutations in four major deafness genes were investigated by sequencing (Group I: 187 patients enrolled between 2011 and 2015) or allele-specific PCR-based universal array (Group II: 319 patients enrolled between 2016 and 2017). The investigated genes included GJB2 (c.35delG, c.176_191del16, c.235delC, c.299-300delAT), SLC26A4 (c.2168A > G, c.919-2A > G), mtDNA 12SrRNA (m.1555A > G, m.1494C > T), and GJB3 (c.538C > T). Furthermore, whole coding region sequencing or improved multiplex ligation detection reaction (IMLDR) were performed for patients who carried mono-allelic variants of GJB2 and SLC26A4, in order to detect other mutations among these patients. RESULTS GJB2 mutations were detected in 22.92% (116/506) of the entire cohort and SLC26A4 mutations were found in 6.52% (33/506) of the cohort. GJB3 mutations were detected in 0.79% (4/506) of the cohort. The mutation rate of mitochondrial DNA 12SrRNA in our patients was 17.40% (88/506), including 17.00% (86/506) with the m.1555A > G mutation and 0.40% (2/506) with the m.1494C > T mutation. The allelic frequency of the c.235delC mutation was 14.62% (148/1012), which is significantly higher than that of c.109G > A (33/1012, 3.26%), c.299_300delAT (13/1012, 1.28%), and c.176_191del16 (6/1012, 0.59%). The most common pathogenic mutation of SLC26A4 was the c.919-2A > G mutation (37/1012, 3.66%), followed by c.2168A > G (6/1012, 0.59%), and c.1229C > T (4/1012, 0.40%). Moreover, five rare pathogenic variants of GJB2 and eight rare pathogenic variants of SLC26A4 were identified. CONCLUSION GJB2 is the primary deafness-causing gene in deaf patients from Wenzhou, China; this is consistent with what is observed in most Chinese populations. However, the surprisingly high rate of the m.1555A > G mutation (17.00%) in patients from Wenzhou was significantly higher than in other populations in China. These findings highlight the specificity of the common deafness-causing gene mutation spectrum in the Wenzhou area. This information may be of benefit for genetic counseling and risk assessment for deaf patients from this area.
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Affiliation(s)
- Yan-Bao Xiang
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China.
| | - Shao-Hua Tang
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China; Key Laboratory of Medical Genetic, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China.
| | - Huan-Zheng Li
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China.
| | - Chen-Yang Xu
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China.
| | - Chong Chen
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China.
| | - Yun-Zhi Xu
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China.
| | - Li-Rong Ding
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China; Key Laboratory of Medical Genetic, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China.
| | - Xue-Qin Xu
- Key Laboratory of Birth Defects, Department of Genetics, Wenzhou Central Hospital, Wenzhou, China.
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22
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Zhang M, Han Y, Zhang F, Bai X, Wang H. Mutation spectrum and hotspots of the common deafness genes in 314 patients with nonsyndromic hearing loss in Heze area, China. Acta Otolaryngol 2019; 139:612-617. [PMID: 31107121 DOI: 10.1080/00016489.2019.1609699] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Background: Although, half of the childhood deafness is genetically related, the molecular etiology of hearing impairment has not been demonstrated explicitly. In addition, the mutation spectrums of deafness genes vary among different areas and ethnics. Objectives: To know more about the mutation spectrums of deafness genes in China, we tested the mutations of three common deafness genes (GJB2, SLC26A4, and mtDNA12SrRNA) in a particular deafness population from Heze area. Materials and methods: SNPscan technology was utilized to perform mutation screening for these three common deafness genes in 314 nonsyndromic deaf patients from Heze area. Results: 38.21% (120/314) of these 314 patients with nonsyndromic hearing loss from Heze area were related to the genetic defects in these three deafness genes, including 20.06% (63/314) for GJB2, 15.29% (48/314) for SLC26A4, and 2.87% (9/314) for mtDNA12SrRNA. Furthermore, the mutation hotspots in three deaf genes were GJB2 235delC, SLC26A4 c.919-2A > G, and mtDNA12SrRNA 1555A > G, respectively, distinct from hotspots reported in other regions worldwide. Conclusion: Our results disclosed a special and unique mutation spectrum of these three common deaf genes in Heze deaf population.
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Affiliation(s)
- Meng Zhang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong Provincial ENT Hospital Affiliated to Shandong University, Jinan, P.R. China
- Key Laboratory of Otorhinolaryngology, National Health Commission (Shandong University), Jinan, P.R. China
- Shandong Provincial Key Laboratory of Otology, Jinan, P.R. China
- Shandong Institute of Otolaryngology, Jinan, P.R. China
| | - Yuechen Han
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong Provincial ENT Hospital Affiliated to Shandong University, Jinan, P.R. China
- Key Laboratory of Otorhinolaryngology, National Health Commission (Shandong University), Jinan, P.R. China
- Shandong Provincial Key Laboratory of Otology, Jinan, P.R. China
- Shandong Institute of Otolaryngology, Jinan, P.R. China
| | - Fengguo Zhang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong Provincial ENT Hospital Affiliated to Shandong University, Jinan, P.R. China
- Key Laboratory of Otorhinolaryngology, National Health Commission (Shandong University), Jinan, P.R. China
- Shandong Provincial Key Laboratory of Otology, Jinan, P.R. China
- Shandong Institute of Otolaryngology, Jinan, P.R. China
| | - Xiaohui Bai
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong Provincial ENT Hospital Affiliated to Shandong University, Jinan, P.R. China
- Key Laboratory of Otorhinolaryngology, National Health Commission (Shandong University), Jinan, P.R. China
- Shandong Provincial Key Laboratory of Otology, Jinan, P.R. China
- Shandong Institute of Otolaryngology, Jinan, P.R. China
| | - Haibo Wang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong Provincial ENT Hospital Affiliated to Shandong University, Jinan, P.R. China
- Key Laboratory of Otorhinolaryngology, National Health Commission (Shandong University), Jinan, P.R. China
- Shandong Provincial Key Laboratory of Otology, Jinan, P.R. China
- Shandong Institute of Otolaryngology, Jinan, P.R. China
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23
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Lesus J, Arias K, Kulaga J, Sobkiv S, Patel A, Babu V, Kambalyal A, Patel M, Padron F, Mozaffari P, Jayakumar A, Ghatalah L, Laban N, Bahari R, Perkins G, Lysakowski A. Why study inner ear hair cell mitochondria? HNO 2019; 67:429-433. [PMID: 30969353 DOI: 10.1007/s00106-019-0662-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
In several systems of the body (muscle, liver, nerves), new studies have examined the internal structure of mitochondria and brought to light striking new findings about how mitochondria are constructed and how their structure affects cell function. In the inner ear field, however, we have little structural knowledge about hair cell and supporting cell mitochondria, and virtually none about mitochondrial subtypes or how they function in health and disease. The need for such knowledge is discussed in this short review.
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Affiliation(s)
- J Lesus
- Dept. of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St., M/C 512, 60612, Chicago, IL, USA
| | - K Arias
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - J Kulaga
- Dept. of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St., M/C 512, 60612, Chicago, IL, USA
| | - S Sobkiv
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - A Patel
- Dept. of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St., M/C 512, 60612, Chicago, IL, USA
| | - V Babu
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - A Kambalyal
- Dept. of Economics, University of Illinois at Chicago, Chicago, IL, USA
| | - M Patel
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - F Padron
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - P Mozaffari
- Dept. of Economics, University of Illinois at Chicago, Chicago, IL, USA
| | - A Jayakumar
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - L Ghatalah
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - N Laban
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - R Bahari
- Dept. of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - G Perkins
- National Center for Microscopy and Imaging Research (NCMIR), University of California, San Diego, La Jolla, CA, USA
| | - A Lysakowski
- Dept. of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St., M/C 512, 60612, Chicago, IL, USA. .,Dept. of Otolaryngology, University of Illinois at Chicago, Chicago, IL, USA.
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24
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Nguyen T, Jeyakumar A. Genetic susceptibility to aminoglycoside ototoxicity. Int J Pediatr Otorhinolaryngol 2019; 120:15-19. [PMID: 30743189 DOI: 10.1016/j.ijporl.2019.02.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 12/27/2018] [Accepted: 02/01/2019] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Aminoglycosides are a well-known clinically relevant antibiotic family used to treat bacterial infections in humans and animals and can produce toxic side effects. Aminoglycoside-induced hearing loss (HL) has been shown to have a genetic susceptibility. Mitochondrial DNA mutations have been implicated in inherited and acquired hearing impairment. OBJECTIVE Literature review of genetic mutations associated with aminoglycoside-induced ototoxicity. METHODS PubMed was accessed from 1993 to 2017 using the search terms "aminoglycoside, genetic, ototoxicity, hearing loss". Exclusion criteria consisted of a literature in a language other than English, uncompleted or ongoing studies, literature with non-hearing related diseases, literature on ototoxicity due to cisplatin/carboplatin based chemotherapy, literature on ototoxicity from loop diuretics, animal studies, literature studying oto-protective agents, and literature without documented aminoglycoside exposure. RESULTS 108 articles were originally identified, and 25 articles were included in our review. Mitochondrial 12S rRNA mutations were identified in all 25 studies in a total of 220 patients. Eight studies identified A1555G mutation as primary genetic factor underlying HL in cases of aminoglycoside-induced ototoxicity. The next most common mutation identified was C1494T. DISCUSSION Mitochondrial 12s rRNA mutation A1555G was present in American, Chinese, Arab-Israeli, Spanish and Mongolian ethnicities. All mutations leading to aminoglycoside ototoxicity were mitochondrial mutations. CONCLUSIONS Consideration of preexisting genetic defects may be valuable in treatments involving aminoglycosides. In particular populations such as those of Chinese origin, clinicians should continue to consider the increased susceptibility to aminoglycosides.
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Affiliation(s)
- Tien Nguyen
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
| | - Anita Jeyakumar
- Division of Otolaryngology, Department of Surgery, Akron Childrens Hospital, Akron, OH, 44308, USA.
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25
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Deterioration in Distortion Product Otoacoustic Emissions in Auditory Neuropathy Patients With Distinct Clinical and Genetic Backgrounds. Ear Hear 2019; 40:184-191. [PMID: 29688962 DOI: 10.1097/aud.0000000000000586] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVES Auditory neuropathy (AN) is a clinical disorder characterized by the absence of auditory brainstem response and presence of otoacoustic emissions. A gradual loss of otoacoustic emissions has been reported for some cases of AN. Such cases could be diagnosed as cochlear hearing loss and lead to misunderstanding of the pathology when patients first visit clinics after the loss of otoacoustic emissions. The purpose of this study was to investigate the time course of changes in distortion product otoacoustic emissions (DPOAEs) in association with patients' genetic and clinical backgrounds, including the use of hearing aids. DESIGN DPOAE measurements from 31 patients with AN were assessed. Genetic analyses for GJB2, OTOF, and mitochondrial m.1555A> G and m.3243A> G mutations were conducted for all cases, and the analyses for CDH23 and OPA1 were conducted for the selected cases. Patients who were younger than 10 years of age at the time of AN diagnosis were designated as the pediatric AN group (22 cases), and those who were 18 years of age or older were designated as the adult AN group (9 cases). DPOAE was measured at least twice in all patients. The response rate for DPOAEs was defined and analyzed. RESULTS The pediatric AN group comprised 10 patients with OTOF mutations, 1 with GJB2 mutations, 1 with OPA1 mutation, and 10 with indefinite causes. Twelve ears (27%) showed no change in DPOAE, 20 ears (46%) showed a decrease in DPOAE, and 12 ears (27%) lost DPOAE. Loss of DPOAE occurred in one ear (2%) at 0 years of age and four ears (9%) at 1 year of age. The time courses of DPOAEs in patients with OTOF mutations were divided into those with early loss and those with no change, indicating that the mechanism for deterioration of DPOAEs includes not only the OTOF mutations but also other common modifier factors. Most, but not all, AN patients who used hearing aids showed deterioration of DPOAEs after the start of using hearing aids. A few AN patients also showed deterioration of DPOAEs before using hearing aids. The adult AN group comprised 2 patients with OPA1 mutations, 2 with OTOF mutations, and 5 with indefinite causes. Four ears (22%) showed no change in DPOAE, 13 ears (72%) showed a decrease, and one ear (6%) showed a loss of DPOAE. Although the ratio of DPOAE decrease was higher in the adult AN group than in the pediatric AN group, the ratio of DPOAE loss was lower in the adult AN group. DPOAE was not lost in all four ears with OPA1 mutations and in all four ears with OTOF mutations in the adult group. CONCLUSIONS DPOAE was decreased or lost in approximately 70% of pediatric and about 80% of adult AN patients. Eleven percent of pediatric AN patients lost DPOAEs by 1 year of age. Genetic factors were thought to have influenced the time course of DPOAEs in the pediatric AN group. In most adult AN patients, DPOAE was rarely lost regardless of the genetic cause.
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Igumnova V, Veidemane L, Vīksna A, Capligina V, Zole E, Ranka R. The prevalence of mitochondrial mutations associated with aminoglycoside-induced deafness in ethnic Latvian population: the appraisal of the evidence. J Hum Genet 2018; 64:199-206. [PMID: 30523288 DOI: 10.1038/s10038-018-0544-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 11/02/2018] [Accepted: 11/02/2018] [Indexed: 11/09/2022]
Abstract
Aminoglycosides are potent antibiotics which are used to treat severe gram-negative infections, neonatal sepsis, and multidrug-resistant tuberculosis. Ototoxicity is a well-known side effect of aminoglycosides, and a rapid, profound, and irreversible hearing loss can occur in predisposed individuals. MT-RNR1 gene encoding the mitochondrial ribosomal 12S subunit is a hot spot for aminoglycoside-induced hearing loss mutations, however, a variability in the nature and frequency of genetic changes in different populations exists. The objective of this study was to analyze MT-RNR1 gene mutations in a Baltic-speaking Latvian population, and to estimate the prevalence of such genetic changes in the population-specific mitochondrial haplogroups. In the cohort of 191 ethnic non-related Latvians, the presence of two deafness-associated mutations, m.1555A>G and m.827A>G, three potentially pathogenic variations, m.961insC(n), m.961T>G and m.951G>A, and one unknown substitution, m961T>A was detected, and the aggregate frequency of all variants was 7.3%. All genetic changes were detected in samples belonged to the haplogroups H, U, T, and J. The presence of several aminoglycoside ototoxicity-related MT-RNR1 gene mutations in Baltic-speaking Latvian population indicates the necessity to include ototoxicity-related mutation analysis in the future studies in order to determine the feasibility of DNA screening for patients before administration of aminoglycoside therapy.
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Affiliation(s)
- Viktorija Igumnova
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia.,Department of Pharmaceutical Chemistry, Rīga Stradinš University, Dzirciema Str. 16, Riga, LV-1007, Latvia
| | - Lauma Veidemane
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia
| | - Anda Vīksna
- Centre of Tuberculosis and Lung Diseases, Riga East University Hospital, Stopiņi region, Upeslejas, LV-2118, Latvia
| | - Valentina Capligina
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia
| | - Egija Zole
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia
| | - Renate Ranka
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia. .,Department of Pharmaceutical Chemistry, Rīga Stradinš University, Dzirciema Str. 16, Riga, LV-1007, Latvia.
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Moassass F, Al-Halabi B, Nweder MS, Al-Achkar W. Investigation of the mtDNA mutations in Syrian families with non-syndromic sensorineural hearing loss. Int J Pediatr Otorhinolaryngol 2018; 113:110-114. [PMID: 30173967 DOI: 10.1016/j.ijporl.2018.07.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 07/16/2018] [Accepted: 07/17/2018] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Hearing loss is a common sensory disorder, and at least 50% of cases are due to a genetic etiology. Several mitochondrial DNA mutations (mtDNA) have been reported to be associated with nonsyndromic hearing loss (NSHL) in different population. However, There is no previous available data about the frequency of mtDNA mutations as etiology for deafness in Syrian. The aim of present study is to investigate the incidence of common mt DNA mutations in our families with congenital hearing loss and not related to the ototoxicity or aminoglycosides. METHODS A total of 50 deaf families were enrolled in the present study. Direct sequencing and PCR-RFLP methods were employed to detect seven mt DNA mutations, including A1555G, A3243G, C1494T, G3316A, T7510C, A7445G, and 7472insC. RESULTS Our results revealed a high prevalence of mt DNA mutation (10%) in deaf families (5/50). In surprising, the unexpected mutations were observed. The G3316A mutation was found in 2 families as homoplasmic genotype. Also, we found the homoplasmic and heteroplasmic genotype for the C1494T mutation in two families. In one family the heteroplasmic genotype for T7510C mutation was observed; this family harbor 35delG mutation in GJB2 gene. None of the common mtDNA mutations (A1555G, A3243G) and other mutations (A7445G, 7472insC) were detected here. CONCLUSION Our findings indicate to significant contribution of the mt DNA mutations in our families with NSHL. The presented data is the first report about mt DNA and it will improve the genetic counseling of hearing impaired in Syrian families.
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Affiliation(s)
- Faten Moassass
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria
| | - Bassel Al-Halabi
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria
| | - Mohamad Sayah Nweder
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria
| | - Walid Al-Achkar
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria.
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28
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Zhao P, Lin L, Lan L. Analysis of mutation spectrum of common deafness-causing genes in Hakka newborns in southern China by semiconductor sequencing. Medicine (Baltimore) 2018; 97:e12285. [PMID: 30235673 PMCID: PMC6160144 DOI: 10.1097/md.0000000000012285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 08/15/2018] [Indexed: 11/27/2022] Open
Abstract
Hearing loss is a common neurosensory disorder, approximately half of the cases are caused by genetic factors, and approximately 70% of hereditary hearing impairments are nonsyndromic hearing loss (NSHL). The mutations of GJB2 (gap junction beta-2 protein), GJB3 (gap junction beta-3 protein), SLC26A4 (solute carrier family 26 member 4), and MT-RNR1 (mitochondrially encoded 12S RNA) are the most common inherited causes of NSHL. Because of different genetic backgrounds, the mutation spectrum of these common deafness-causing genes varies among different regions in China. Because no data are known on these mutations among the Hakka population of Southern China, we aim to investigate the mutation spectrum to add these to neonatal screening and genetic counseling. A total of 1252 blood samples from newborns have been detected by semiconductor sequencing for 100 mutations loci of 18 deafness-causing genes. Of the participants, 95 subjects carried deafness-causing genes mutations with the carrier rate of 7.59%. The mutation frequencies of GJB2, SLC26A4, GJB3, and mitochondrial genes were 3.04%, 3.51%, 0.16%, and 0.88%, respectively. We followed up subjects with single-gene homozygous or compound heterozygous mutations. Our study firstly analyzed deafness-causing genes mutation spectrum in Hakka population, providing evidence for future neonatal screening and genetic counseling in this area.
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Affiliation(s)
- Pingsen Zhao
- Clinical Core Laboratory
- Center for Precision Medicine, Meizhou People's Hospital (Huangtang Hospital), Meizhou Hospital Affiliated to Sun Yat-sen University
- Guangdong Provincial Engineering and Technology Research Center for Molecular Diagnostics of Cardiovascular Diseases
- Meizhou Municipal Engineering and Technology Research Center for Molecular Diagnostics of Cardiovascular Diseases
- Meizhou Municipal Engineering and Technology Research Center for Molecular Diagnostics of Major Genetic Disorders
- Prenatal Diagnosis Center, Meizhou People's Hospital (Huangtang Hospital), Meizhou Hospital Affiliated to Sun Yat-sen University, Meizhou, P. R. China
| | - Lifang Lin
- Clinical Core Laboratory
- Center for Precision Medicine, Meizhou People's Hospital (Huangtang Hospital), Meizhou Hospital Affiliated to Sun Yat-sen University
- Guangdong Provincial Engineering and Technology Research Center for Molecular Diagnostics of Cardiovascular Diseases
- Meizhou Municipal Engineering and Technology Research Center for Molecular Diagnostics of Cardiovascular Diseases
- Meizhou Municipal Engineering and Technology Research Center for Molecular Diagnostics of Major Genetic Disorders
- Prenatal Diagnosis Center, Meizhou People's Hospital (Huangtang Hospital), Meizhou Hospital Affiliated to Sun Yat-sen University, Meizhou, P. R. China
| | - Liubing Lan
- Prenatal Diagnosis Center, Meizhou People's Hospital (Huangtang Hospital), Meizhou Hospital Affiliated to Sun Yat-sen University, Meizhou, P. R. China
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Wu L, Li R, Chen J, Chen Y, Yang M, Wu Q. Analysis of mitochondrial A1555G mutation in infants with hearing impairment. Exp Ther Med 2018; 15:5307-5313. [PMID: 29805548 PMCID: PMC5958681 DOI: 10.3892/etm.2018.6078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 02/23/2018] [Indexed: 11/06/2022] Open
Abstract
Mutations in the mitochondrial 12S ribosomal RNA gene have been identified to be associated with deafness. Among these, the A to G transition at position 1555 is one of the most common pathogenic mutations associated with hearing loss. In order to evaluate the allele frequency of this mutation in infants with hearing loss, the A1555G mutation was screened in 300 deaf children and 100 age- and sex-matched healthy subjects. Consequently, 5 patients with this mutation were identified, whereas the mutation was absent in healthy controls. Among the patients with the mutation, only one had an obvious family history of hearing impairment. Notably, this pedigree manifested a high penetrance of deafness. In particular, the penetrance of deafness was 80 and 40%, when the aminoglycoside antibiotics (AmAn) was included or excluded, respectively. Clinical evaluation of this family exhibited a wide degree of hearing loss. Furthermore, screening for the complete mitochondrial genes revealed the occurrence of A1555G and transfer (t)RNAThr T15943C mutations, together with other genetic variations belonging to East Asian haplogroup C. Notably, the T15943C mutation, located at the T arm of tRNAThr, could disrupt the 63T-55A base-pairing and impair tRNA metabolism. Therefore, it was hypothesized that the combination of A1555G and T15943C mutations may result in mitochondrial dysfunction that is responsible for deafness. Screening for A1555G, as well as other potential pathogenic mutations in the mitochondrial genome, is critical for clinical diagnosis and prevention of hearing impairment.
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Affiliation(s)
- Lihua Wu
- Department of Otolaryngology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou, Fujian 350001, P.R. China
| | - Ruiyu Li
- Department of Otolaryngology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou, Fujian 350001, P.R. China
| | - Juan Chen
- Department of Otolaryngology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou, Fujian 350001, P.R. China
| | - Yanping Chen
- Department of Obstetrics, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou, Fujian 350001, P.R. China
| | - Meijun Yang
- Department of Neonatology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou, Fujian 350001, P.R. China
| | - Qing Wu
- Department of Neonatology, Fujian Provincial Maternal and Child Health Care Hospital, Fuzhou, Fujian 350001, P.R. China
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Huang B, Han M, Wang G, Huang S, Zeng J, Yuan Y, Dai P. Genetic mutations in non-syndromic deafness patients in Hainan Province have a different mutational spectrum compared to patients from Mainland China. Int J Pediatr Otorhinolaryngol 2018; 108:49-54. [PMID: 29605365 DOI: 10.1016/j.ijporl.2018.02.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/18/2018] [Accepted: 02/11/2018] [Indexed: 10/18/2022]
Abstract
OBJECTIVES To provide appropriate genetic testing and counseling for non-syndromic hearing impairment patients in Hainan Province, an island in the South China Sea. METHODS 299 unrelated students with non-syndromic hearing loss who attended a special education school in Hainan Province were enrolled in this study. Three prominent deafness-related genes (GJB2, SLC26A4, and mtDNA 12S rRNA) were analyzed using Sanger sequencing. RESULTS GJB2 mutations were detected in 32.78% (98/299) of the entire cohort; however, only 5.69% (17/299) had two confirmed pathogenic mutations. The most common mutation observed in this population was c.109G > A in the GJB2 gene, with an allelic frequency of 15.05% (90/598), which is significantly higher than that reported in previous cohorts. A total of 16 patients had two confirmed pathogenic SLC26A4 gene mutations, and 16 patients had one. The IVS7-2A > G mutation was the most commonly observed, with an allelic frequency of 3.51% (21/598). Three patients had a m.1555A > G mutation in the mtDNA 12S rRNA gene. CONCLUSIONS These results reveal that genetic etiology occurred in 11.71% (35/299) of patients, suggesting that Hainan province have a different mutational spectrum compare to Mainland China in non-syndromic deafness patients, which provide useful information to genetic counseling in Hainan province.
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Affiliation(s)
- Bangqing Huang
- Department of Otorhinolaryngology, Hainan Branch of PLA General Hospital, Sanya 572013, PR China
| | - Mingyu Han
- Department of Otorhinolaryngology, Hainan Branch of PLA General Hospital, Sanya 572013, PR China; Department of Otolaryngology and Genetic Testing Center for Deafness, Chinese PLA General Hospital, Beijing 100853, PR China
| | - Guojian Wang
- Department of Otolaryngology and Genetic Testing Center for Deafness, Chinese PLA General Hospital, Beijing 100853, PR China
| | - ShaSha Huang
- Department of Otolaryngology and Genetic Testing Center for Deafness, Chinese PLA General Hospital, Beijing 100853, PR China
| | - Jialing Zeng
- Department of Otorhinolaryngology, Hainan Branch of PLA General Hospital, Sanya 572013, PR China
| | - Yongyi Yuan
- Department of Otolaryngology and Genetic Testing Center for Deafness, Chinese PLA General Hospital, Beijing 100853, PR China.
| | - Pu Dai
- Department of Otolaryngology and Genetic Testing Center for Deafness, Chinese PLA General Hospital, Beijing 100853, PR China.
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32
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Lanvers-Kaminsky C, Ciarimboli G. Pharmacogenetics of drug-induced ototoxicity caused by aminoglycosides and cisplatin. Pharmacogenomics 2017; 18:1683-1695. [PMID: 29173064 DOI: 10.2217/pgs-2017-0125] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aminoglycosides and the anticancer drug cisplatin can cause permanent hearing loss, which impacts patients' quality of life and results in considerable subsequent costs. Since patients' individual susceptibility to aminoglycoside- and cisplatin-induced ototoxicity varies considerably, strategies are needed to identify patients at risk, who may require alternative treatments or specific protection strategies. For both drugs, various genetic variants were linked to an increased or decreased risk for ototoxicity. Except for the association between the A1555G mitochondrial DNA mutation and aminoglycoside ototoxicity, their evidence is considered low because study cohorts were often small and replication studies either missing or contradictory. This review summarizes the pharmacogenetic markers linked to aminoglycoside- or cisplatin-induced ototoxicity and discusses reasons for replication failure and future perspective.
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Affiliation(s)
- Claudia Lanvers-Kaminsky
- Department of Pediatric Hematology & Oncology, University Children's Hospital of Muenster, Muenster, Germany
| | - Giuliano Ciarimboli
- Experimental Nephrology, Department of Internal Medicine D, University Hospital of Muenster, Muenster, Germany
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33
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Nishio SY, Usami SI. Outcomes of cochlear implantation for the patients with specific genetic etiologies: a systematic literature review. Acta Otolaryngol 2017; 137:730-742. [PMID: 28498079 DOI: 10.1080/00016489.2016.1276303] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
CONCLUSION Most of the cases with gene mutations of intra-cochlear etiology showed relatively good CI outcomes. To progress toward more solid evidence-based CI intervention, a greater number of reports including CI outcomes for specific gene mutations are desired. BACKGROUND Cochlear implantation (CI) is the most important and effective treatment for patients with profound sensorineural hearing loss. However, the outcomes of CI vary among patients. One of the reasons of this heterogeneous outcome for cochlear implantation is thought to be the heterogeneous nature of hearing loss. Indeed, genetic factors, the most common etiology in severe-to-profound hearing loss, might be one of the key determinants of outcomes for CI and electric acoustic stimulation (EAS). Patients with genetic causes involving an 'intra-cochlear' etiology show good CI/EAS outcomes. REVIEW This review article aimed to summarize the reports on CI/EAS outcomes in patients with special genetic causes as well as to assist in future clinical decision-making. Most of the cases were suspected of an intra-cochlear etiology, such as those with GJB2, SLC26A4, and OTOF mutations, which showed relatively good CI outcomes. However, there have only been a limited number of reports on patients with other gene mutations.
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Affiliation(s)
- Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Nagano, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Nagano, Japan
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34
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Subathra M, Ramesh A, Selvakumari M, Karthikeyen NP, Srisailapathy CRS. Genetic Epidemiology of Mitochondrial Pathogenic Variants Causing Nonsyndromic Hearing Loss in a Large Cohort of South Indian Hearing Impaired Individuals. Ann Hum Genet 2017; 80:257-73. [PMID: 27530448 DOI: 10.1111/ahg.12161] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 05/16/2016] [Indexed: 01/28/2023]
Abstract
Mitochondria play a critical role in the generation of metabolic energy in the form of ATP. Tissues and organs that are highly dependent on aerobic metabolism are involved in mitochondrial disorders including nonsyndromic hearing loss (NSHL). Seven pathogenic variants leading to NSHL have so far been reported on two mitochondrial genes: MT-RNR1 encoding 12SrRNA and MT-TS1 encoding tRNA for Ser((UCN)) . We screened 729 prelingual NSHL subjects to determine the prevalence of MT-RNR1 variants at position m.961, m.1555A>G and m.1494C>T, and MT-TS1 m.7445A>G, m.7472insC m.7510T>C and m.7511T>C variants. Mitochondrial pathogenic variants were found in eight probands (1.1%). Five of them were found to have the m.1555A>G variant, two others had m.7472insC and one proband had m.7444G>A. The extended relatives of these probands showed variable degrees of hearing loss and age at onset. This study shows that mitochondrial pathogenic alleles contribute to about 1% prelingual hearing loss. This study will henceforth provide the reference for the prevalence of mitochondrial pathogenic alleles in the South Indian population, which to date has not been estimated. The m.1555A>G variant is a primary predisposing genetic factor for the development of hearing loss. Our study strongly suggests that mitochondrial genotyping should be considered for all hearing impaired individuals and particularly in families where transmission is compatible with maternal inheritance, after ruling out the most common variants.
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Affiliation(s)
- Mahalingam Subathra
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
| | - Arabandi Ramesh
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
| | - Mathiyalagan Selvakumari
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
| | - N P Karthikeyen
- DOAST (Doctrine Oriented Art of Symbiotic Treatment) Hearing Care Center and Integrated Therapy Center for Autism, Anna Nagar West, Chennai, India
| | - C R Srikumari Srisailapathy
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
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35
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Wang Y, Smith C, Parboosingh JS, Khan A, Innes M, Hekimi S. Pathogenicity of two COQ7 mutations and responses to 2,4-dihydroxybenzoate bypass treatment. J Cell Mol Med 2017; 21:2329-2343. [PMID: 28409910 PMCID: PMC5618687 DOI: 10.1111/jcmm.13154] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 02/10/2017] [Indexed: 01/22/2023] Open
Abstract
Primary ubiquinone (co‐enzyme Q) deficiency results in a wide range of clinical features due to mitochondrial dysfunction. Here, we analyse and characterize two mutations in the ubiquinone biosynthetic gene COQ7. One mutation from the only previously identified patient (V141E), and one (L111P) from a 6‐year‐old girl who presents with spasticity and bilateral sensorineural hearing loss. We used patient fibroblast cell lines and a heterologous expression system to show that both mutations lead to loss of protein stability and decreased levels of ubiquinone that correlate with the severity of mitochondrial dysfunction. The severity of L111P is enhanced by the particular COQ7 polymorphism (T103M) that the patient carries, but not by a mitochondrial DNA mutation (A1555G) that is also present in the patient and that has been linked to aminoglycoside‐dependent hearing loss. We analysed treatment with the unnatural biosynthesis precursor 2,4‐dihydroxybenzoate (DHB), which can restore ubiquinone synthesis in cells completely lacking the enzymatic activity of COQ7. We find that the treatment is not beneficial for every COQ7 mutation and its outcome depends on the extent of enzyme activity loss.
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Affiliation(s)
- Ying Wang
- Department of Biology, McGill University, Montréal, Quebec, Canada
| | - Christopher Smith
- Department of Medical Genetics, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Jillian S Parboosingh
- Department of Medical Genetics, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital, Research Institute for Child and Maternal Health, University of Calgary, Calgary, Alberta, Canada
| | - Aneal Khan
- Metabolic Diseases Clinic, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Micheil Innes
- Department of Medical Genetics, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital, Research Institute for Child and Maternal Health, University of Calgary, Calgary, Alberta, Canada
| | - Siegfried Hekimi
- Department of Biology, McGill University, Montréal, Quebec, Canada
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36
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Mutai H, Watabe T, Kosaki K, Ogawa K, Matsunaga T. Mitochondrial mutations in maternally inherited hearing loss. BMC MEDICAL GENETICS 2017; 18:32. [PMID: 28320335 PMCID: PMC5359870 DOI: 10.1186/s12881-017-0389-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 03/02/2017] [Indexed: 11/18/2022]
Abstract
Background Although the mitochondrial DNA (mtDNA) mutations m.1555A > G and m.3243A > G are the primary causes of maternally inherited sensorineural hearing loss (SNHL), several other mtDNA mutations are also reported to be associated with SNHL. Methods Screening of m.1555A > G and m.3243A > G mutations was performed for 145 probands. Nine probands fulfilled the following criteria: 1) bilateral and symmetric SNHL, 2) ≥ 4 family members with SNHL with a maternal trait of inheritance in ≥ 2 generations, 3) onset of SNHL before the age of 40 years, 4) high-frequency SNHL, and 5) no record of environmental factors related to SNHL. Sequencing of additional mtDNA regions was performed for five subjects meeting the clinical criteria, but the screening results were negative. Results Among the nine cases meeting the five clinical criteria detailed above, three had the m.1555A > G mutation in MTRNR1, one had a m.3243A > G mutation in MTTL1, and one case had a m.7511T > C mutation in MTTS1. In the family with the m.7511T > C mutation, penetrance of SNHL among maternally related subjects was 9/17 (53%). The age at onset varied from birth (congenital) to adulthood. Hearing levels varied from normal to moderately impaired, unlike previously reported subjects with this mutation, where some maternal family members presented with profound SNHL. Family members with the m.7511T > C mutation and SNHL did not exhibit any specific clinical characteristics distinct from those of other individuals with SNHL and different mtDNA mutations. Among the 136 probands who did not meet the criteria detailed above, one case had the m.1555A > G mutation, and three cases had the m.3243A > G mutation. Conclusions Since five of nine probands with the clinical criteria used in this study had mtDNA mutations, these criteria may be helpful for identification of candidate patients likely to have mtDNA mutations. Electronic supplementary material The online version of this article (doi:10.1186/s12881-017-0389-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hideki Mutai
- Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro, Tokyo, 152-8902, Japan
| | - Takahisa Watabe
- Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Kenjiro Kosaki
- Center for Medical Genetics, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Kaoru Ogawa
- Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan
| | - Tatsuo Matsunaga
- Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro, Tokyo, 152-8902, Japan.
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37
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Kasakura-Kimura N, Masuda M, Mutai H, Masuda S, Morimoto N, Ogahara N, Misawa H, Sakamoto H, Saito K, Matsunaga T. WFS1andGJB2mutations in patients with bilateral low-frequency sensorineural hearing loss. Laryngoscope 2017; 127:E324-E329. [DOI: 10.1002/lary.26528] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/20/2016] [Accepted: 01/10/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Natsuko Kasakura-Kimura
- Division of Hearing and Balance Research; National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center; Tokyo Japan
- Department of Otolaryngology; School of Medicine, Kyorin University; Tokyo Japan
| | - Masatsugu Masuda
- Division of Hearing and Balance Research; National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center; Tokyo Japan
- Department of Otolaryngology; School of Medicine, Kyorin University; Tokyo Japan
| | - Hideki Mutai
- Division of Hearing and Balance Research; National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center; Tokyo Japan
| | - Sawako Masuda
- Department of Otolaryngology; National Mie Hospital; Mie Japan
| | - Noriko Morimoto
- Division of Otolaryngology; National Center for Child Health and Development; Tokyo Japan
| | - Noboru Ogahara
- Department of Otolaryngology; Kanagawa Children's Medical Center; Kanagawa Japan
| | - Hayato Misawa
- Department of Otolaryngology; National Hospital Organization Nagoya Medical Center; Aichi Japan
| | - Hirokazu Sakamoto
- Department of Otolaryngology; Hyogo Prefectural Kobe Children's Hospital; Hyogo Japan
| | - Koichiro Saito
- Department of Otolaryngology; School of Medicine, Kyorin University; Tokyo Japan
| | - Tatsuo Matsunaga
- Division of Hearing and Balance Research; National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center; Tokyo Japan
- Medical Genetics Center; National Hospital Organization Tokyo Medical Center; Tokyo Japan
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38
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Gao Z, Chen Y, Guan MX. Mitochondrial DNA mutations associated with aminoglycoside induced ototoxicity. J Otol 2017; 12:1-8. [PMID: 29937831 PMCID: PMC6011804 DOI: 10.1016/j.joto.2017.02.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/07/2017] [Accepted: 02/08/2017] [Indexed: 11/25/2022] Open
Abstract
Aminoglycosides (AmAn) are widely used for their great efficiency against gram-negative bacterial infections. However, they can also induce ototoxic hearing loss, which has affected millions of people around the world. As previously reported, individuals bearing mitochondrial DNA mutations in the 12S rRNA gene, such as m.1555A>G and m.1494C>T, are more prone to AmAn-induced ototoxicity. These mutations cause human mitochondrial ribosomes to more closely resemble bacterial ribosomes and enable a stronger aminoglycoside interaction. Consequently, exposure to AmAn can induce or worsen hearing loss in these individuals. Furthermore, a wide range of severity and penetrance of hearing loss was observed among families carrying these mutations. Studies have revealed that these mitochondria mutations are the primary molecular mechanism of genetic susceptibility to AmAn ototoxicity, though nuclear modifier genes and mitochondrial haplotypes are known to modulate the phenotypic manifestation.
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Affiliation(s)
- Zewen Gao
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Ye Chen
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Min-Xin Guan
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
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39
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Lanvers-Kaminsky C, Zehnhoff-Dinnesen AA, Parfitt R, Ciarimboli G. Drug-induced ototoxicity: Mechanisms, Pharmacogenetics, and protective strategies. Clin Pharmacol Ther 2017; 101:491-500. [PMID: 28002638 DOI: 10.1002/cpt.603] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 11/21/2016] [Accepted: 12/08/2016] [Indexed: 01/08/2023]
Abstract
Drug ototoxicity limits the quality of life of patients after treatment, having serious consequences, especially for psychosocial development of children. Although the ototoxicity of many drugs resolves after treatment discontinuation, the use of platinum derivatives and aminoglycosides is associated with permanent hearing loss. In this review, we have listed ototoxic drugs and the mechanisms by which they damage the ears. Moreover, possible protective strategies and important methods for early detection of ototoxic effects are discussed.
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Affiliation(s)
- C Lanvers-Kaminsky
- Department of Pediatric Hematology and Oncology, University Children's Hospital of Muenster, Muenster, Germany
| | - Ag Am Zehnhoff-Dinnesen
- Department of Phoniatrics and Pedaudiology, University Hospital of Muenster, Muenster, Germany
| | - R Parfitt
- Department of Phoniatrics and Pedaudiology, University Hospital of Muenster, Muenster, Germany
| | - G Ciarimboli
- Experimental Nephrology, Department of Internal Medicine D, University Hospital of Muenster, Muenster, Germany
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40
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Patel M, Agarwal K, Arshad Q, Hariri M, Rea P, Seemungal BM, Golding JF, Harcourt JP, Bronstein AM. Intratympanic methylprednisolone versus gentamicin in patients with unilateral Ménière's disease: a randomised, double-blind, comparative effectiveness trial. Lancet 2016; 388:2753-2762. [PMID: 27865535 DOI: 10.1016/s0140-6736(16)31461-1] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 08/12/2016] [Accepted: 08/16/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND Ménière's disease is characterised by severe vertigo attacks and hearing loss. Intratympanic gentamicin, the standard treatment for refractory Ménière's disease, reduces vertigo, but damages vestibular function and can worsen hearing. We aimed to assess whether intratympanic administration of the corticosteroid methylprednisolone reduces vertigo compared with gentamicin. METHODS In this double-blind comparative effectiveness trial, patients aged 18-70 years with refractory unilateral Ménière's disease were enrolled at Charing Cross Hospital (London, UK) and Leicester Royal Infirmary (Leicester, UK). Patients were randomly assigned (1:1) by a block design to two intratympanic methylprednisolone (62·5 mg/mL) or gentamicin (40 mg/mL) injections given 2 weeks apart, and were followed up for 2 years. All investigators and patients were masked to treatment allocation. The primary outcome was vertigo frequency over the final 6 months (18-24 months after injection) compared with the 6 months before the first injection. Analyses were done in the intention-to-treat population, and then per protocol. This trial is registered with ClinicalTrials.gov, number NCT00802529. FINDINGS Between June 19, 2009, and April 15, 2013, 256 patients with Ménière's disease were screened, 60 of whom were enrolled and randomly assigned: 30 to gentamicin and 30 to methylprednisolone. In the intention-to-treat analysis (ie, all 60 patients), the mean number of vertigo attacks in the final 6 months compared with the 6 months before the first injection (primary outcome) decreased from 19·9 (SD 16·7) to 2·5 (5·8) in the gentamicin group (87% reduction) and from 16·4 (12·5) to 1·6 (3·4) in the methylprednisolone group (90% reduction; mean difference -0·9, 95% CI -3·4 to 1·6). Patients whose vertigo did not improve after injection (ie, non-responders) after being assessed by an unmasked clinician were eligible for additional injections given by a masked clinician (eight patients in the gentamicin group vs 15 in the methylprednisolone group). Two non-responders switched from methylprednisolone to gentamicin. Both drugs were well tolerated with no safety concerns. Six patients reported one adverse event each: three in the gentamicin group and three in the methylprednisolone group. The most common adverse event was minor ear infections, which was experienced by one patient in the gentamicin group and two in the methylprednisolone group. INTERPRETATION Methylprednisolone injections are a non-ablative, effective treatment for refractory Ménière's disease. The choice between methylprednisolone and gentamicin should be made based on clinical knowledge and patient circumstances. FUNDING Ménière's Society and National Institute for Health Research Imperial Biomedical Research Centre.
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Affiliation(s)
- Mitesh Patel
- Neuro-otology Unit, Division of Brain Sciences, Charing Cross Hospital Campus, Imperial College London, London, UK
| | - Kiran Agarwal
- Neuro-otology Unit, Division of Brain Sciences, Charing Cross Hospital Campus, Imperial College London, London, UK
| | - Qadeer Arshad
- Neuro-otology Unit, Division of Brain Sciences, Charing Cross Hospital Campus, Imperial College London, London, UK
| | - Mohamed Hariri
- Ear, Nose and Throat Department, Charing Cross Hospital, London, UK
| | - Peter Rea
- Ear, Nose and Throat Department, Leicester Royal Infirmary, Leicester University Hospitals, Leicester, UK
| | - Barry M Seemungal
- Neuro-otology Unit, Division of Brain Sciences, Charing Cross Hospital Campus, Imperial College London, London, UK
| | - John F Golding
- Neuro-otology Unit, Division of Brain Sciences, Charing Cross Hospital Campus, Imperial College London, London, UK; Department of Psychology, University of Westminster, London, UK
| | - Jonny P Harcourt
- Ear, Nose and Throat Department, Charing Cross Hospital, London, UK
| | - Adolfo M Bronstein
- Neuro-otology Unit, Division of Brain Sciences, Charing Cross Hospital Campus, Imperial College London, London, UK.
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41
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Han KH, Kim AR, Kim MY, Ahn S, Oh SH, Song JH, Choi BY. Establishment of a Flexible Real-Time Polymerase Chain Reaction-Based Platform for Detecting Prevalent Deafness Mutations Associated with Variable Degree of Sensorineural Hearing Loss in Koreans. PLoS One 2016; 11:e0161756. [PMID: 27583405 PMCID: PMC5008798 DOI: 10.1371/journal.pone.0161756] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 08/11/2016] [Indexed: 11/19/2022] Open
Abstract
Many cutting-edge technologies based on next-generation sequencing (NGS) have been employed to identify candidate variants responsible for sensorineural hearing loss (SNHL). However, these methods have limitations preventing their wide clinical use for primary screening, in that they remain costly and it is not always suitable to analyze massive amounts of data. Several different DNA chips have been developed for screening prevalent mutations at a lower cost. However, most of these platforms do not offer the flexibility to add or remove target mutations, thereby limiting their wider use in a field that requires frequent updates. Therefore, we aimed to establish a simpler and more flexible molecular diagnostic platform based on ethnicity-specific mutation spectrums of SNHL, which would enable bypassing unnecessary filtering steps in a substantial portion of cases. In addition, we expanded the screening platform to cover varying degrees of SNHL. With this aim, we selected 11 variants of 5 genes (GJB2, SLC26A4, MTRNR1, TMPRSS3, and CDH23) showing high prevalence with varying degrees in Koreans and developed the U-TOP™ HL Genotyping Kit, a real-time PCR-based method using the MeltingArray technique and peptide nucleic acid probes. The results of 271 DNA samples with wild type sequences or mutations in homo- or heterozygote form were compared between the U-TOP™ HL Genotyping Kit and Sanger sequencing. The positive and negative predictive values were 100%, and this method showed perfect agreement with Sanger sequencing, with a Kappa value of 1.00. The U-TOP™ HL Genotyping Kit showed excellent performance in detecting varying degrees and phenotypes of SNHL mutations in both homozygote and heterozygote forms, which are highly prevalent in the Korean population. This platform will serve as a useful and cost-effective first-line screening tool for varying degrees of genetic SNHL and facilitate genome-based personalized hearing rehabilitation for the Korean population.
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Affiliation(s)
- Kyu-Hee Han
- Department of Otorhinolaryngology-Head and Neck Surgery, National Medical Center, Seoul, Korea
| | - Ah Reum Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Min Young Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Soyeon Ahn
- Medical Research Collaborating Center, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Seung-Ha Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Ju Hun Song
- Department of Otorhinolaryngology-Head and Neck Surgery, National Medical Center, Seoul, Korea
| | - Byung Yoon Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
- Wide River Institute of Immunology, Seoul National University College of Medicine, Hongcheon, Korea
- * E-mail:
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Kanno A, Mutai H, Namba K, Morita N, Nakano A, Ogahara N, Sugiuchi T, Ogawa K, Matsunaga T. Frequency and specific characteristics of the incomplete partition type III anomaly in children. Laryngoscope 2016; 127:1663-1669. [DOI: 10.1002/lary.26245] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 07/11/2016] [Accepted: 07/14/2016] [Indexed: 11/05/2022]
Affiliation(s)
- Ayako Kanno
- Division of Hearing and Balance Research; National Institute of Sensory Organs; National Hospital Organization Tokyo Medical Center; Tokyo Japan
- Department of Otolaryngology; Inagi Municipal Hospital; Tokyo Japan
- Department of Otolaryngology; Keio University School of Medicine; Tokyo Japan
| | - Hideki Mutai
- Division of Hearing and Balance Research; National Institute of Sensory Organs; National Hospital Organization Tokyo Medical Center; Tokyo Japan
| | - Kazunori Namba
- Division of Hearing and Balance Research; National Institute of Sensory Organs; National Hospital Organization Tokyo Medical Center; Tokyo Japan
| | - Noriko Morita
- Department of Otolaryngology; Kobari General Hospital; Chiba Japan
| | - Atsuko Nakano
- Division of Otolaryngology; Chiba Children's Hospital; Chiba Japan
| | - Noboru Ogahara
- Department of Otorhinolaryngology; Kanagawa Children's Medical Center; Kanagawa Japan
| | - Tomoko Sugiuchi
- Department of Otolaryngology; Kanto Rosai Hospital; Kanagawa Japan
| | - Kaoru Ogawa
- Department of Otolaryngology; Keio University School of Medicine; Tokyo Japan
| | - Tatsuo Matsunaga
- Division of Hearing and Balance Research; National Institute of Sensory Organs; National Hospital Organization Tokyo Medical Center; Tokyo Japan
- Medical Genetics Center; National Hospital Organization Tokyo Medical Center; Tokyo Japan
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Angeli SI, Yan D, Telischi F, Balkany TJ, Ouyang XM, Du LL, Eshraghi A, Goodwin L, Liu XZ. Etiologic diagnosis of sensorineural hearing loss in adults. Otolaryngol Head Neck Surg 2016; 132:890-5. [PMID: 15944560 DOI: 10.1016/j.otohns.2005.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE: To determine the etiology of adult-onset sensorineural hearing loss. STUDY DESIGN AND SETTING: This is a prospective cohort study of 60 adult subjects with bilateral sensorineural hearing loss of no obvious etiology by medical history and physical examination. These patients were evaluated at an academic medical center and underwent evaluation by high-resolution computed tomography of the temporal bone, autoimmune panel, and DNA testing for mutations of both the GJB2 gene and the mitochondrial DNA (1555A>G and 7445A>G). RESULTS: An etiologic diagnosis was achieved in 6 patients: cochlear otosclerosis, 1 case; dilated vestibular aqueduct, 1 case; a mitochondrial DNA 7445A>G mutation, 3 cases; and a mitochondrial DNA 1555A>G mutation, 1 case. CONCLUSION: This result underscores the importance of a search for the etiology of a hearing deficit in adult patients. There are specific interventions now available for the management of hearing-impaired patients with cochlear otosclerosis and mitochondrial DNA mutations.
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Affiliation(s)
- Simon I Angeli
- Department of Otolaryngology, University of Miami School of Medicine, Florida 33101, USA.
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Li H, Wang B, Liu D, Wang T, Li Q, Wang W, Li H. SNPscan as a high-performance screening tool for mutation hotspots of hearing loss-associated genes. Genomics 2015; 106:83-7. [DOI: 10.1016/j.ygeno.2015.05.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 05/15/2015] [Accepted: 05/17/2015] [Indexed: 11/16/2022]
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Zhu J, Cao Q, Zhang N, Ge J, Sun D, Feng Q. A study of deafness-related genetic mutations as a basis for strategies to prevent hereditary hearing loss in Hebei, China. Intractable Rare Dis Res 2015; 4:131-8. [PMID: 26361564 PMCID: PMC4561242 DOI: 10.5582/irdr.2015.01018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 07/26/2015] [Accepted: 08/05/2015] [Indexed: 11/05/2022] Open
Abstract
Hearing loss is the most common sensory disorder, and at least 50% of cases are due to a genetic etiology. Two-thirds of individuals with congenital deafness are nonsyndromic. Among the nonsyndromic forms, the large majority are monogenic autosomal recessive traits. The current work summarizes mutations in the GJB2, SLC26A4, 12SrRNA, and GJB3 and their prevalence in 318 students with autosomal recessive nonsyndromic hearing loss at schools for the deaf or special needs schools in 9 cities in Hebei Province, China. Deafness gene mutations were identified in 137 students via a gene chip, time-of-flight mass spectrometry, fluorescence quantitative PCR, and gene sequencing. Mutations were detected at a rate of 43.08%. A homozygous mutation of the GJB2 gene was found in 16 students (5.03%), a heterozygous mutation of that gene was found in 38 (11.95%), a homozygous mutation of the SLC26A4 gene was found in 22 (6.92%), a heterozygous mutation of that gene was found in 59 (18.55%), and a heterozygous mutation of the mitochondrial 12SrRNA gene was found in 2 (0.63%). In addition, there were 15 families in which a student's parents had normal hearing. Compound heterozygous mutations of the GJB2 gene were found in 3 families (20%) and mutations of the SLC26A4 gene were found in 9 (60%). Thus, this study has provided a molecular diagnostic basis for the causes of deafness, and this study has also provided a scientific basis for the early prevention of and intervention in deafness.
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Affiliation(s)
- Junzhen Zhu
- Center for Exceptional Care in 3 Areas, The People's Hospital of Hebei Province, Shijiazhuang, Hebei Province, China
| | - Qinying Cao
- The Fourth Hospital of Shijiazhuang, Shijiazhuang, Hebei Province, China
| | - Ning Zhang
- Center for Exceptional Care in 3 Areas, The People's Hospital of Hebei Province, Shijiazhuang, Hebei Province, China
| | - Jun Ge
- The Fourth Hospital of Shijiazhuang, Shijiazhuang, Hebei Province, China
| | - Donglan Sun
- The Fourth Hospital of Shijiazhuang, Shijiazhuang, Hebei Province, China
| | - Qingqi Feng
- Xinji Maternal and Child Health Hospital, Xinji, Hebei Province, China
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Mizutari K, Mutai H, Namba K, Miyanaga Y, Nakano A, Arimoto Y, Masuda S, Morimoto N, Sakamoto H, Kaga K, Matsunaga T. High prevalence of CDH23 mutations in patients with congenital high-frequency sporadic or recessively inherited hearing loss. Orphanet J Rare Dis 2015; 10:60. [PMID: 25963016 PMCID: PMC4451718 DOI: 10.1186/s13023-015-0276-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 04/28/2015] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Mutations in CDH23 are responsible for Usher syndrome 1D and recessive non-syndromic hearing loss. In this study, we revealed the prevalence of CDH23 mutations among patients with specific clinical characteristics. METHODS After excluding patients with GJB2 mutations and mitochondrial m.1555A > G and m.3243A > G mutations, subjects for CDH23 mutation analysis were selected according to the following criteria: 1) Sporadic or recessively inherited hearing loss 2) bilateral non-syndromic congenital hearing loss, 3) no cochlear malformation, 4) a poorer hearing level at high frequencies than at low frequencies, and 5) severe or profound hearing loss at higher frequencies. RESULTS Seventy-two subjects were selected from 621 consecutive probands who did not have environmental causes for their hearing loss. After direct sequencing, 13 of the 72 probands (18.1%) had homozygous or compound heterozygous CDH23 mutations. In total, we identified 16 CDH23 mutations, including five novel mutations. The 16 mutations included 12 missense, two frameshift, and two splice-site mutations. CONCLUSIONS These results revealed that CDH23 mutations are highly prevalent in patients with congenital high-frequency sporadic or recessively inherited hearing loss and that the mutation spectrum was diverse, indicating that patients with these clinical features merit genetic analysis.
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Affiliation(s)
- Kunio Mizutari
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan. .,Department of Otolaryngology-Head and Neck Surgery, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 160-8582, Japan.
| | - Hideki Mutai
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan.
| | - Kazunori Namba
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan.
| | - Yuko Miyanaga
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan.
| | - Atsuko Nakano
- Division of Otorhinolaryngology, Chiba Children's Hospital, 579-1 Hetacho, Midori-ku, Chiba, Chiba, 266-0007, Japan.
| | - Yukiko Arimoto
- Division of Otorhinolaryngology, Chiba Children's Hospital, 579-1 Hetacho, Midori-ku, Chiba, Chiba, 266-0007, Japan.
| | - Sawako Masuda
- Department of Otorhinolaryngology, National Mie Hospital, 357 Osato-Kubota, Tsu, Mie, 514-0125, Japan.
| | - Noriko Morimoto
- Division of Otolaryngology, National Center for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo, 157-8535, Japan.
| | - Hirokazu Sakamoto
- Department of Otorhinolaryngology, Hyogo Prefectural Kobe Children's Hospital, 1-1-1 Takakuradai, Suma-ku, Kobe, Hyogo, 654-0081, Japan.
| | - Kimitaka Kaga
- National Institute of Sensory Organs, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan.
| | - Tatsuo Matsunaga
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan. .,Medical Genetics Center, National Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan.
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Tang X, Zheng J, Ying Z, Cai Z, Gao Y, He Z, Yu H, Yao J, Yang Y, Wang H, Chen Y, Guan MX. Mitochondrial tRNA(Ser(UCN)) variants in 2651 Han Chinese subjects with hearing loss. Mitochondrion 2015; 23:17-24. [PMID: 25968158 DOI: 10.1016/j.mito.2015.05.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 04/14/2015] [Accepted: 05/04/2015] [Indexed: 12/17/2022]
Abstract
Mutations in the mitochondrial DNA have been associated with hearing loss. However, the prevalence and spectrum of mitochondrial tRNA mutations in hearing-impaired subjects are poorly understood. In this report, we have investigated the prevalence and spectrum of mitochondrial tRNA(Ser(UCN)) mutations in a large cohort of 2651 Han Chinese subjects with hearing loss. The clinical evaluation showed that 744 subjects (432 males and 312 females) had a history of exposure to aminoglycosides and other probands exhibited nonsyndromic hearing loss. Mutational analysis of tRNA(Ser(UCN)) gene identified 9 (8 known and 1 novel) variants. The prevalence of the known deafness-associated 7511T>C, 7505T>C and 7445A>C mutations was 0.04%, 0.04% and 0.04%, respectively. Other variants were evaluated by the evolutionary conservation, allelic frequency of Chinese controls, potential structural and functional alterations and pedigree analysis. Three variants were polymorphisms, while the 7444G>A, 7471DelG and 7496A>G variants were putative deafness-associated mutations. These putative deafness-associated variants accounted for 0.68% cases of hearing-impaired subjects in this cohort. The low penetrance of hearing loss in pedigrees carrying one of these putative deafness-associated mutations indicated that the mutation(s) is necessary but itself insufficient to produce a clinical phenotype. Other genetic or environmental factor(s) may influence the phenotypic manifestation of these tRNA(Ser(UCN)) mutations. Moreover, mtDNAs in 20 probands carrying one of the putative deafness-associated mutations were widely dispersed among 8 Eastern Asian haplogroups. In particular, the occurrences of haplogroups D4a, M22, and H2 in patients carrying the deafness-associated variants were higher than those in Chinese controls. These data further support that the mitochondrial tRNA(Ser(UCN)) gene is the hot spot for mutations associated with hearing loss. Thus, our findings may provide valuable information for the further understanding of pathophysiology and management of hearing loss.
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Affiliation(s)
- Xiaowen Tang
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jing Zheng
- Institute of Genetics, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhengbiao Ying
- Department of Otolaryngology, Wenling People's Hospital, Wenzhou Medical University, Wenling, Zhejiang, China
| | - Zhaoyang Cai
- Department of Otolaryngology, Wenling People's Hospital, Wenzhou Medical University, Wenling, Zhejiang, China
| | - Yinglong Gao
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zheyun He
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Han Yu
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Juan Yao
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yaling Yang
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Hui Wang
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ye Chen
- Institute of Genetics, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Min-Xin Guan
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China; Institute of Genetics, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
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Mutations in the two ribosomal RNA genes in mitochondrial DNA among Finnish children with hearing impairment. BMC MEDICAL GENETICS 2015; 16:3. [PMID: 25650108 PMCID: PMC4410458 DOI: 10.1186/s12881-015-0145-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 01/17/2015] [Indexed: 01/31/2023]
Abstract
Background Mutations in the two MT-RNR genes in mitochondrial DNA can cause hearing impairment that presents with variable severity and age of onset. In order to study the prevalence of mutations in MT-RNR1 and MT-RNR2 genes among Finnish children, we studied a ten-year cohort of hearing impaired children born in Northern Finland. Methods We studied children, who had been born in Northern Finland in 1993–2002 and who had been ascertained to have hearing impairment by 31 December 2007. Samples from 103 children were sequenced in order to find mutations in the MT-RNR1 and MT-RNR2 genes. Results One child harboured the pathogenic m.1555A > G mutation in MT-RNR1 suggesting a frequency of 4.4/100,000 in the Finnish paediatric population. In addition, eight rare variants and 13 polymorphisms were found in MT-RNR1 and MT-RNR2 genes. Five of the rare variants were deemed to be haplogroup-specific polymorphisms rather than putative pathogenic mutations, while the remaining three variants have been reported in various haplogroups. Among them m.990 T > C occurs at a conserved site. Conclusions The presence of m.990 T > C variant in various haplogroups and the rather high degree of conservation at this site suggest that this transition is a pathogenic rather than homoplasic neutral variant. Identification of further patients with m.990 T > C and segregation analysis in their families should help in determining the pathogenic potential of this variant.
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Fassad MR, Desouky LM, Asal S, Abdalla EM. Screening for the mitochondrial A1555G mutation among Egyptian patients with non-syndromic, sensorineural hearing loss. INTERNATIONAL JOURNAL OF MOLECULAR EPIDEMIOLOGY AND GENETICS 2014; 5:200-204. [PMID: 25755848 PMCID: PMC4348701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Accepted: 12/30/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND & AIM Hearing loss is the most frequent form of neurosensory deficit in humans. Although the majority of hereditary hearing loss is due to nuclear gene mutations, it has become clear the significant contribution of mitochondrial genes. The first mitochondrial mutation shown to cause non-syndromic hearing loss in humans was the A1555G mutation in the small ribosomal RNA gene (12S rRNA). It has been detected in hundreds of families of different ethnic backgrounds, making it one of the prevalent genetic causes of hearing loss currently identified. However, there are major differences between ethnic groups regarding the frequency of this mutation. Few studies have been made in Arab countries, especially in Egypt. Here we report the prevalence of the mitochondrial mutation A1555G among patients with non-syndromic hearing loss (NSHL) and in healthy individuals with normal hearing in the Egyptian population. SUBJECTS & METHODS The study was conducted on 97 patients with SNHL and 300 unrelated healthy Egyptian individuals, with normal hearing, as normal control subjects. Polymerase chain reaction followed by restriction enzyme digestion was used to screen the DNA samples of all subjects for the A1555G mutation. RESULTS Participants included 97 cases with SNHL, 46 males and 51 females. Their ages ranged from 1 month to 65 years with the mean age 6.2 years (SD ± 8.2). Paternal consanguinity was reported in 46% (35/76) of the studied families. The A1555G mutation was found in one of the 97 patients (1.3%), while it has not been detected in the 300 control samples. CONCLUSION Our findings indicate that, even in absence of exposure to aminoglycosides, the mitochondrial A1555G mutation is one of the potential causes of non-syndromic SNHL in the Egyptian population.
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Affiliation(s)
- Mahmoud R Fassad
- Department of Human Genetics, Medical Research Institute, Alexandria UniversityEgypt
| | - Lubna M Desouky
- Department of Human Genetics, Medical Research Institute, Alexandria UniversityEgypt
| | - Samir Asal
- Department of Audiology, Alexandria Faculty of MedicineEgypt
| | - Ebtesam M Abdalla
- Department of Human Genetics, Medical Research Institute, Alexandria UniversityEgypt
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