1
|
Jing P, Mei X, Zhang YY, Zheng FJ, Luo XM, Liu LJ, Yu HH, Zhang XB. Major depressive disorder is correlated with the mitochondrial ND1 T3394C mutation in two Han Chinese families: Two case reports. World J Psychiatry 2023; 13:75-83. [PMID: 36925947 PMCID: PMC10011944 DOI: 10.5498/wjp.v13.i2.75] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/09/2022] [Accepted: 01/16/2023] [Indexed: 02/17/2023] Open
Abstract
BACKGROUND Major depressive disorder (MDD) is the most frequent reason of disabled people in the world, as reported by the World Health Organization. However, the diagnosis of MDD is mainly based on clinical symptoms.
CASE SUMMARY The clinical, genetic, and molecular characteristics of two Chinese families with MDD are described in this study. There were variable ages of onset and severity in depression among the families. Both Chinese families had a very low pre-valence of MDD. The mitochondrial genomes of these pedigrees were sequenced and indicated a homoplasmic T3394C (Y30H) mutation, with the polymorphism located at a highly conserved tyrosine at position 30 of ND1. The analysis also revealed unique sets of mitochondrial DNA (mtDNA) polymorphisms orig-inating from haplogroups M9a3 and M9a.
CONCLUSION This finding of the T3394C mutation in two unrelated depressed patients provides strong evidence that this mutation may have a part in the etiology of MDD. However, In these two Chinese families having the T3394C mutation, no functional mtDNA mutation was observed. Therefore, T3394C mutations are related with MDD, and the phenotypic manifestation of these mutations may be affected by changes in nuclear genes or environmental factors.
Collapse
Affiliation(s)
- Pan Jing
- Department of Psychiatric, Ningbo Kangning Hospital, Ningbo 315201, Zhejiang Province, China
| | - Xi Mei
- Department of Psychiatric, Ningbo Kangning Hospital, Ningbo 315201, Zhejiang Province, China
| | - Yuan-Yuan Zhang
- Department of Psychiatric, Ningbo Kangning Hospital, Ningbo 315201, Zhejiang Province, China
| | - Fei-Jie Zheng
- Department of Psychiatric, Ningbo Kangning Hospital, Ningbo 315201, Zhejiang Province, China
| | - Xiao-Min Luo
- Department of Psychiatric, Ningbo Kangning Hospital, Ningbo 315201, Zhejiang Province, China
| | - Ling-Jiang Liu
- Department of Psychiatric, Ningbo Kangning Hospital, Ningbo 315201, Zhejiang Province, China
| | - Hai-Hang Yu
- Department of Psychiatric, Ningbo Kangning Hospital, Ningbo 315201, Zhejiang Province, China
| | - Xiao-Bin Zhang
- Department of Psychiatry, Suzhou Guangji Hospital, Suzhou 215003, Jiangsu Province, China
| |
Collapse
|
2
|
Carelli V, Newman NJ, Yu-Wai-Man P, Biousse V, Moster ML, Subramanian PS, Vignal-Clermont C, Wang AG, Donahue SP, Leroy BP, Sergott RC, Klopstock T, Sadun AA, Rebolleda Fernández G, Chwalisz BK, Banik R, Girmens JF, La Morgia C, DeBusk AA, Jurkute N, Priglinger C, Karanjia R, Josse C, Salzmann J, Montestruc F, Roux M, Taiel M, Sahel JA. Indirect Comparison of Lenadogene Nolparvovec Gene Therapy Versus Natural History in Patients with Leber Hereditary Optic Neuropathy Carrying the m.11778G>A MT-ND4 Mutation. Ophthalmol Ther 2023; 12:401-429. [PMID: 36449262 PMCID: PMC9834474 DOI: 10.1007/s40123-022-00611-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/28/2022] [Indexed: 12/05/2022] Open
Abstract
INTRODUCTION Lenadogene nolparvovec is a promising novel gene therapy for patients with Leber hereditary optic neuropathy (LHON) carrying the m.11778G>A ND4 mutation (MT-ND4). A previous pooled analysis of phase 3 studies showed an improvement in visual acuity of patients injected with lenadogene nolparvovec compared to natural history. Here, we report updated results by incorporating data from the latest phase 3 trial REFLECT in the pool, increasing the number of treated patients from 76 to 174. METHODS The visual acuity of 174 MT-ND4-carrying patients with LHON injected in one or both eyes with lenadogene nolparvovec from four pooled phase 3 studies (REVERSE, RESCUE and their long-term extension trial RESTORE; and REFLECT trial) was compared to the spontaneous evolution of an external control group of 208 matched patients from 11 natural history studies. RESULTS Treated patients showed a clinically relevant and sustained improvement in their visual acuity when compared to natural history. Mean improvement versus natural history was - 0.30 logMAR (+ 15 ETDRS letters equivalent) at last observation (P < 0.01) with a maximal follow-up of 3.9 years after injection. Most treated eyes were on-chart as compared to less than half of natural history eyes at 48 months after vision loss (89.6% versus 48.1%; P < 0.01) and at last observation (76.1% versus 44.4%; P < 0.01). When we adjusted for covariates of interest (gender, age of onset, ethnicity, and duration of follow-up), the estimated mean gain was - 0.43 logMAR (+ 21.5 ETDRS letters equivalent) versus natural history at last observation (P < 0.0001). Treatment effect was consistent across all phase 3 clinical trials. Analyses from REFLECT suggest a larger treatment effect in patients receiving bilateral injection compared to unilateral injection. CONCLUSION The efficacy of lenadogene nolparvovec in improving visual acuity in MT-ND4 LHON was confirmed in a large cohort of patients, compared to the spontaneous natural history decline. Bilateral injection of gene therapy may offer added benefits over unilateral injection. TRIAL REGISTRATION NUMBERS NCT02652780 (REVERSE); NCT02652767 (RESCUE); NCT03406104 (RESTORE); NCT03293524 (REFLECT); NCT03295071 (REALITY).
Collapse
Affiliation(s)
- Valerio Carelli
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto delle Scienze Neurologiche di Bologna, Programma di Neurogenetica, Via Altura, 3, 40139, Bologna, BO, Italy.
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy.
| | - Nancy J Newman
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurological Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Patrick Yu-Wai-Man
- Department of Clinical Neurosciences, Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK
- Moorfields Eye Hospital, NHS Foundation Trust, London, UK
- Institute of Ophthalmology, University College London, London, UK
| | - Valerie Biousse
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurological Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Mark L Moster
- Department of Neurology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
- Department of Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
| | - Prem S Subramanian
- Sue Anschutz-Rodgers University of Colorado Eye Center, University of Colorado School of Medicine, Aurora, CO, USA
| | - Catherine Vignal-Clermont
- Department of Neuro Ophthalmology and Emergencies, Rothschild Foundation Hospital, Paris, France
- Centre d'Investigation Clinique, Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, Paris, France
| | - An-Guor Wang
- Department of Ophthalmology, Taipei Veterans General Hospital, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Sean P Donahue
- Department of Ophthalmology, Neurology, and Pediatrics, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Vanderbilt University, Nashville, TN, USA
| | - Bart P Leroy
- Department of Ophthalmology and Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
- Department of Head & Skin, Ghent University, Ghent, Belgium
| | - Robert C Sergott
- Department of Neurology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
- Department of Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Alfredo A Sadun
- David Geffen, Doheny Eye Institute, School of Medicine, University of California, Los Angeles, CA, USA
| | | | - Bart K Chwalisz
- Department of Ophthalmology, Massachusetts Eye & Ear, Harvard Medical School, Boston, MA, USA
| | - Rudrani Banik
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jean François Girmens
- Centre d'Investigation Clinique, Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, Paris, France
| | - Chiara La Morgia
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto delle Scienze Neurologiche di Bologna, Programma di Neurogenetica, Via Altura, 3, 40139, Bologna, BO, Italy
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
| | - Adam A DeBusk
- Department of Neurology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
- Department of Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
| | - Neringa Jurkute
- Moorfields Eye Hospital, NHS Foundation Trust, London, UK
- Institute of Ophthalmology, University College London, London, UK
- Department of Neuro-Ophthalmology, The National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, UK
| | - Claudia Priglinger
- Department of Ophthalmology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Rustum Karanjia
- David Geffen, Doheny Eye Institute, School of Medicine, University of California, Los Angeles, CA, USA
- Department of Ophthalmology, University of Ottawa Eye, Ottawa, ON, Canada
| | - Constant Josse
- eXYSTAT, Data Management and Statistic, Malakoff, France
| | | | | | | | | | - José-Alain Sahel
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
- Rothschild Foundation Hospital, Paris, France
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Institut Hospitalo-Universitaire FOReSIGHT, INSERM-DGOS CIC 1423, Paris, France
| |
Collapse
|
3
|
Tagliani S, Malaventura C, Ceccato C, Parmeggiani F, Suppiej A. Leber Mitochondrial Optic Neuropathy in Pediatric Females With Focus on Very Early Onset Cases. J Child Neurol 2023; 38:5-15. [PMID: 36659874 DOI: 10.1177/08830738221149962] [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] [Indexed: 01/21/2023]
Abstract
The aim of this study was to describe the phenotype of Leber hereditary optic neuropathy occurring in pediatric females. This disease generally affects young adult males, but it can occur also in females, and research data in this population is lacking. The very early onset can challenge the diagnosis and delay treatment. We searched PubMed through February 2021 and identified 226 pediatric females with genetically confirmed Leber hereditary optic neuropathy and added a new case of a 3-year-old female. The male-female ratio was 1.8:1; the mean onset age in females was 11 years with the onset at 3 years of age occurring in 3 females only. Acute onset with mild visual impairment was the most common presentation, associated with optic disc edema in 16%. Differential diagnoses are pseudotumor cerebri, optic nerve drusen and optic neuritis. The outcome is poor with partial recovery in 50%, despite some receiving Idebenone therapy.
Collapse
Affiliation(s)
- Sara Tagliani
- Department of Medical Sciences, Pediatric Section, University Hospital of Ferrara, Ferrara, Italy
| | - Cristina Malaventura
- Department of Medical Sciences, Pediatric Section, University Hospital of Ferrara, Ferrara, Italy
| | | | - Francesco Parmeggiani
- Department of Translational Medicine and for Romagna, 9299University of Ferrara, Ferrara, Italy.,ERN-EYE Network - Center for Retinitis Pigmentosa of Veneto Region, 196013Camposampiero Hospital, Padova, Italy
| | - Agnese Suppiej
- Department of Medical Sciences, Pediatric Section, University Hospital of Ferrara, Ferrara, Italy.,87812Robert Hollman Foundation, Padova, Italy.,ERN-EYE Network - Center for Retinitis Pigmentosa of Veneto Region, 196013Camposampiero Hospital, Padova, Italy
| |
Collapse
|
4
|
Ji Y, Zhang J, Liang M, Meng F, Zhang M, Mo JQ, Wang M, Guan MX. Mitochondrial tRNA variants in 811 Chinese probands with Leber's hereditary optic neuropathy. Mitochondrion 2022; 65:56-66. [PMID: 35623556 DOI: 10.1016/j.mito.2022.05.003] [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: 03/08/2022] [Revised: 04/26/2022] [Accepted: 05/22/2022] [Indexed: 11/27/2022]
Abstract
Leber's hereditary optic neuropathy (LHON) is the maternal inheritance of eye disorder. LHON-linked mitochondrial DNA (mtDNA) mutations affect the ND1, ND4 or ND6 genes encoding essential subunits of complex I. However, the role of mitochondrial tRNA defects in the pathogenesis of LHON is poorly understood. In this report, Sanger sequence analysis of 22 mitochondrial tRNA genes identified 139 variants in a cohort of 811 Han Chinese probands and 485 control Chinese subjects. Among these, 32 (4 known and 28 novel/putative) tRNA variants in 69 probands may contribute to pathogenesis of LHON, as these exhibited (1) present in <1% of controls; (2) evolutionary conservation; (3) potential and significance of structural and functional modifications. Such variants may have potentially compromised structural and functional aspects in the processing of tRNAs, structure stability, tRNA charging, or codon-anticodon interactions during translation. These 32 variants presented either singly or with multiple mutations, with the primary LHON-linked ND1 3640G>A, ND4 11778G>A or ND6 14484T>C mutations in the probands. The thirty-eight pedigrees carrying only one of tRNA variants exhibited relatively low penetrances of LHON, ranging from 5.7% to 42.9%, with an average of 19%. Strikingly, the average penetrances of optic neuropathy among 33 Chinese families carrying both a known/putative tRNA variant and a primary LHON-associated mtDNA mutation were 40.1%. These findings suggested that mitochondrial tRNA variants represent a significant causative factor for LHON, accounting for 8.75% cases in this cohort. These new insights may lead to beneficial applications in the pathophysiology, disease management, and genetic counseling of LHON.
Collapse
Affiliation(s)
- Yanchun Ji
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310058, China; Institute of Genetics, Zhejiang University, School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Juanjuan Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Min Liang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Feilong Meng
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310058, China; Institute of Genetics, Zhejiang University, School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Minglian Zhang
- Department of Ophthalmology, Hebei Provincial Eye Hospital, Xingtai, Hebei 051730, China
| | - Jun Q Mo
- Department of Pathology, Rady Children's Hospital, University of California at San Diego School of Medicine, San Diego, California 92123, USA
| | - Meng Wang
- Institute of Genetics, Zhejiang University, School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Min-Xin Guan
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310058, China; Institute of Genetics, Zhejiang University, School of Medicine, Hangzhou, Zhejiang 310058, China; Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Zhejiang University, Hangzhou, Zhejiang 310058, China; Division of Mitochondrial Biomedicine, Joint Institute of Genetics and Genome Medicine between Zhejiang University and University of Toronto, Hangzhou, Zhejiang, China.
| |
Collapse
|
5
|
Establishing risk of vision loss in Leber hereditary optic neuropathy. Am J Hum Genet 2021; 108:2159-2170. [PMID: 34670133 PMCID: PMC8595929 DOI: 10.1016/j.ajhg.2021.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 09/27/2021] [Indexed: 11/24/2022] Open
Abstract
We conducted an updated epidemiological study of Leber hereditary optic neuropathy (LHON) in Australia by using registry data to establish the risk of vision loss among different LHON mutations, sex, age at onset, and mitochondrial haplogroup. We identified 96 genetically unrelated LHON pedigrees, including 56 unpublished pedigrees, and updated 40 previously known pedigrees, comprising 620 affected individuals and 4,948 asymptomatic carriers. The minimum prevalence of vision loss due to LHON in Australia in 2020 was one in 68,403 individuals. Although our data confirm some well-established features of LHON, the overall risk of vision loss among those with a LHON mutation was lower than reported previously-17.5% for males and 5.4% for females. Our findings confirm that women, older adults, and younger children are also at risk. Furthermore, we observed a higher incidence of vision loss in children of affected mothers as well as in children of unaffected women with at least one affected brother. Finally, we confirmed our previous report showing a generational fall in prevalence of vision loss among Australian men. Higher reported rates of vision loss in males with a LHON mutation are not supported by our work and other epidemiologic studies. Accurate knowledge of risk is essential for genetic counseling of individuals with LHON mutations. This knowledge could also inform the detection and validation of potential biomarkers and has implications for clinical trials of treatments aimed at preventing vision loss in LHON because an overestimated risk may lead to an underpowered study or a false claim of efficacy.
Collapse
|
6
|
Newman NJ, Yu-Wai-Man P, Carelli V, Biousse V, Moster ML, Vignal-Clermont C, Sergott RC, Klopstock T, Sadun AA, Girmens JF, La Morgia C, DeBusk AA, Jurkute N, Priglinger C, Karanjia R, Josse C, Salzmann J, Montestruc F, Roux M, Taiel M, Sahel JA. Intravitreal Gene Therapy vs. Natural History in Patients With Leber Hereditary Optic Neuropathy Carrying the m.11778G>A ND4 Mutation: Systematic Review and Indirect Comparison. Front Neurol 2021; 12:662838. [PMID: 34108929 PMCID: PMC8181419 DOI: 10.3389/fneur.2021.662838] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 03/25/2021] [Indexed: 01/22/2023] Open
Abstract
Objective: This work aimed to compare the evolution of visual outcomes in Leber hereditary optic neuropathy (LHON) patients treated with intravitreal gene therapy to the spontaneous evolution in prior natural history (NH) studies. Design: A combined analysis of two phase three randomized, double-masked, sham-controlled studies (REVERSE and RESCUE) and their joint long-term extension trial (CLIN06) evaluated the efficacy of rAAV2/2-ND4 vs. 11 pooled NH studies used as an external control. Subjects: The LHON subjects carried the m.11778G>A ND4 mutation and were aged ≥15 years at onset of vision loss. Methods: A total of 76 subjects received a single intravitreal rAAV2/2-ND4 injection in one eye and sham injection in the fellow eye within 1 year after vision loss in REVERSE and RESCUE. Both eyes were considered as treated due to the rAAV2/2-ND4 treatment efficacy observed in the contralateral eyes. Best corrected visual acuity (BCVA) from REVERSE, RESCUE, and CLIN06 up to 4.3 years after vision loss was compared to the visual acuity of 208 NH subjects matched for age and ND4 genotype. The NH subjects were from a LHON registry (REALITY) and from 10 NH studies. A locally estimated scatterplot smoothing (LOESS), non-parametric, local regression model was used to modelize visual acuity curves over time, and linear mixed model was used for statistical inferences. Main Outcome Measures: The main outcome measure was evolution of visual acuity from 12 months after vision loss, when REVERSE and RESCUE patients had been treated with rAAV2/2-ND4. Results: The LOESS curves showed that the BCVA of the treated patients progressively improved from month 12 to 52 after vision loss. At month 48, there was a statistically and clinically relevant difference in visual acuity of -0.33 logarithm of the minimal angle of resolution (LogMAR) (16.5 ETDRS letters equivalent) in favor of treated eyes vs. NH eyes (p < 0.01). Most treated eyes (88.7%) were on-chart at month 48 as compared to 48.1% of the NH eyes (p < 0.01). The treatment effect at last observation remained statistically and clinically significant when adjusted for age and duration of follow-up (-0.32 LogMAR, p < 0.0001). Conclusions: The m.11778G>A LHON patients treated with rAAV2/2-ND4 exhibited an improvement of visual acuity over more than 4 years after vision loss to a degree not demonstrated in NH studies. Clinical Trial Registration: NCT02652767, NCT02652780, NCT03406104, and NCT03295071.
Collapse
Affiliation(s)
- Nancy J. Newman
- Departments of Ophthalmology, Neurology and Neurological Surgery, Emory University School of Medicine, Atlanta, GA, United States
- *Correspondence: Nancy J. Newman
| | - Patrick Yu-Wai-Man
- Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom
- Moorfields Eye Hospital National Health Service Foundation Trust, London, United Kingdom
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Valerio Carelli
- Istituto di Ricovero e Cura a Carattere Scientifico Istituto delle Scienze Neurologiche di Bologna, Unitá Operativa Compless Clinica Neurologica, Bologna, Italy
- Unit of Neurology, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Valerie Biousse
- Departments of Ophthalmology, Neurology and Neurological Surgery, Emory University School of Medicine, Atlanta, GA, United States
| | - Mark L. Moster
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, United States
| | - Catherine Vignal-Clermont
- Department of Neuro Ophthalmology and Emergencies, A. de Rothschild Foundation Hospital, Paris, France
- Centre d'investigation Clinique, Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, Paris, France
| | - Robert C. Sergott
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, United States
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
- German Center for Neurodegenerative Diseases, Munich, Germany
- Munich Cluster for Systems Neurology, Munich, Germany
| | - Alfredo A. Sadun
- Doheny Eye Institute, School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Jean-François Girmens
- Centre d'investigation Clinique, Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, Paris, France
| | - Chiara La Morgia
- Istituto di Ricovero e Cura a Carattere Scientifico Istituto delle Scienze Neurologiche di Bologna, Unitá Operativa Compless Clinica Neurologica, Bologna, Italy
| | - Adam A. DeBusk
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, United States
| | - Neringa Jurkute
- Moorfields Eye Hospital National Health Service Foundation Trust, London, United Kingdom
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Claudia Priglinger
- Department of Ophthalmology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Rustum Karanjia
- Doheny Eye Institute, School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Department of Ophthalmology, University of Ottawa Eye, Ottawa, ON, Canada
| | - Constant Josse
- eXYSTAT, Data Management and Statistic, Malakoff, France
| | | | | | | | | | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- A. de Rothschild Foundation Hospital, Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- CHNO des Quinze-Vingts, Institut Hospitalo-Universitaire FOReSIGHT, INSERM-DGOS CIC 1423, Paris, France
| |
Collapse
|
7
|
Ji Y, Zhang J, Lu Y, Yi Q, Chen M, Xie S, Mao X, Xiao Y, Meng F, Zhang M, Yang R, Guan MX. Complex I mutations synergize to worsen the phenotypic expression of Leber's hereditary optic neuropathy. J Biol Chem 2020; 295:13224-13238. [PMID: 32723871 DOI: 10.1074/jbc.ra120.014603] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/24/2020] [Indexed: 12/15/2022] Open
Abstract
Leber's hereditary optic neuropathy (LHON) is a maternal inheritance of eye disease because of the mitochondrial DNA (mtDNA) mutations. We previously discovered a 3866T>C mutation within the gene for the ND1 subunit of complex I as possibly amplifying disease progression for patients bearing the disease-causing 11778G>A mutation within the gene for the ND4 subunit of complex I. However, whether and how the ND1 mutation exacerbates the ND4 mutation were unknown. In this report, we showed that four Chinese families bearing both m.3866T>C and m.11778G>A mutations exhibited higher penetrances of LHON than 6 Chinese pedigrees carrying only the m.3866T>C mutation or families harboring only the m.11778G>A mutation. The protein structure analysis revealed that the m.3866T>C (I187T) and m.11778G>A (R340H) mutations destabilized the specific interactions with other residues of ND1 and ND4, thereby altering the structure and function of complex I. Cellular data obtained using cybrids, constructed by transferring mitochondria from the Chinese families into mtDNA-less (ρ°) cells, demonstrated that the mutations perturbed the stability, assembly, and activity of complex I, leading to changes in mitochondrial ATP levels and membrane potential and increasing the production of reactive oxygen species. These mitochondrial dysfunctions promoted the apoptotic sensitivity of cells and decreased mitophagy. Cybrids bearing only the m.3866T>C mutation displayed mild mitochondrial dysfunctions, whereas those harboring both m.3866T>C and m.11778G>A mutations exhibited greater mitochondrial dysfunctions. These suggested that the m.3866T>C mutation acted in synergy with the m.11778G>A mutation, aggravating mitochondrial dysfunctions and contributing to higher penetrance of LHON in these families carrying both mtDNA mutations.
Collapse
Affiliation(s)
- Yanchun Ji
- Department of Genetics and Metabolic Diseases, Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Division of Medical Genetics and Genomics, Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Juanjuan Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yuanyuan Lu
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Qiuzi Yi
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Mengquan Chen
- Department of Lab Medicine, Wenzhou Hospital of Traditional Chinese Medicine, Wenzhou, Zhejiang, China
| | - Shipeng Xie
- Department of Ophthalmology, Hebei Provincial Eye Hospital, Xingtai, Hebei, China
| | - Xiaoting Mao
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yun Xiao
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Feilong Meng
- Department of Genetics and Metabolic Diseases, Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Division of Medical Genetics and Genomics, Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Minglian Zhang
- Department of Ophthalmology, Hebei Provincial Eye Hospital, Xingtai, Hebei, China
| | - Rulai Yang
- Department of Genetics and Metabolic Diseases, Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
| | - Min-Xin Guan
- Division of Medical Genetics and Genomics, Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Key Lab of Reproductive Genetics, Ministry of Education of PRC, Zhejiang University, Hangzhou, Zhejiang, China; Joint Institute of Genetics and Genomic Medicine between Zhejiang University and University of Toronto, Hangzhou, Zhejiang, China.
| |
Collapse
|
8
|
Chen D, Zhao Q, Xiong J, Lou X, Han Q, Wei X, Xie J, Li X, Zhou H, Shen L, Yang Y, Fang H, Lyu J. Systematic analysis of a mitochondrial disease-causing ND6 mutation in mitochondrial deficiency. Mol Genet Genomic Med 2020; 8:e1199. [PMID: 32162843 PMCID: PMC7216815 DOI: 10.1002/mgg3.1199] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 02/07/2020] [Accepted: 02/14/2020] [Indexed: 12/24/2022] Open
Abstract
Background The m.14487T>C mutation is recognized as a diagnostic mutation of mitochondrial disease during the past 16 years, emerging evidence suggests that mutant loads of m.14487T>C and disease phenotype are not closely correlated. Methods Immortalized lymphocytes were generated by coculturing the Epstein–Barr virus and lymphocytes from m.14487T>C carrier Chinese patient with Leigh syndrome. Fifteen cytoplasmic hybrid (cybrid) cell lines were generated by fusing mtDNA lacking 143B cells with platelets donated by patients. Mitochondrial function was systematically analyzed at transcriptomic, metabolomic, and biochemical levels. Results Unlike previous reports, we found that the assembly of mitochondrial respiratory chain complexes, mitochondrial respiration, and mitochondrial OXPHOS function was barely affected in cybrid cells carrying homoplastic m.14487T>C mutation. Mitochondrial dysfunction associated transcriptomic and metabolomic reprogramming were not detected in cybrid carrying homoplastic m.14487T>C. However, we found that mitochondrial function was impaired in patient‐derived immortalized lymphocytes. Conclusion Our data revealed that m.14487T>C mutation is insufficient to cause mitochondrial deficiency; additional modifier genes may be involved in m.14487T>C‐associated mitochondrial disease. Our results further demonstrated that a caution should be taken by solely use of m.14487T>C mutation for molecular diagnosis of mitochondrial disease.
Collapse
Affiliation(s)
- Deyu Chen
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Qiongya Zhao
- Zhejiang Provincial People's Hospital, Affiliated People's Hospital of Hangzhou Medical College, College of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
| | - Jingting Xiong
- Department of Laboratory Medicine, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoting Lou
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Qinxia Han
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Xiujuan Wei
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Jie Xie
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Xueyun Li
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Huaibin Zhou
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Lijun Shen
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Yanling Yang
- Department of Pediatrics, Peking University First Hospital, Peking University, Beijing, China
| | - Hezhi Fang
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China
| | - Jianxin Lyu
- Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life sciences, Wenzhou Medical University, Wenzhou, China.,Zhejiang Provincial People's Hospital, Affiliated People's Hospital of Hangzhou Medical College, College of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
| |
Collapse
|
9
|
Ji Y, Zhang J, Yu J, Wang Y, Lu Y, Liang M, Li Q, Jin X, Wei Y, Meng F, Gao Y, Cang X, Tong Y, Liu X, Zhang M, Jiang P, Zhu T, Mo JQ, Huang T, Jiang P, Guan MX. Contribution of mitochondrial ND1 3394T>C mutation to the phenotypic manifestation of Leber's hereditary optic neuropathy. Hum Mol Genet 2020; 28:1515-1529. [PMID: 30597069 DOI: 10.1093/hmg/ddy450] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 11/05/2018] [Accepted: 12/22/2018] [Indexed: 11/14/2022] Open
Abstract
Mitochondrial DNA (mtDNA) mutations have been associated with Leber's hereditary optic neuropathy (LHON) and their pathophysiology remains poorly understood. In this study, we investigated the pathophysiology of a LHON susceptibility allele (m.3394T>C, p.30Y>H) in the Mitochondrial (MT)-ND1 gene. The incidence of m.3394T>C mutation was 2.7% in the cohort of 1741 probands with LHON. Extremely low penetrances of LHON were observed in 26 pedigrees carrying only m.3394T>C mutation, while 21 families bearing m.3394T>C, together with m.11778G>A or m.14484T>C mutation, exhibited higher penetrance of LHON than those in families carrying single mtDNA mutation(s). The m.3394T>C mutation disrupted the specific electrostatic interactions between Y30 of p.MT-ND1 with the sidechain of E4 and backbone carbonyl group of M1 of NDUFA1 (NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 1) of complex I, thereby altering the structure and function of complex I. We demonstrated that these cybrids bearing only m.3394T>C mutation caused mild mitochondrial dysfunctions and those harboring both m.3394T>C and m.11778G>A mutations exhibited greater mitochondrial dysfunctions than cybrids carrying only m.11778G>A mutation. In particular, the m.3394T>C mutation altered the stability of p.MT-ND1 and complex I assembly. Furthermore, the m.3394T>C mutation decreased the activities of mitochondrial complexes I, diminished mitochondrial ATP levels and membrane potential and increased the production of reactive oxygen species in the cybrids. These m.3394T>C mutation-induced alterations aggravated mitochondrial dysfunctions associated with the m.11778G>A mutation. These resultant biochemical defects contributed to higher penetrance of LHON in these families carrying both mtDNA mutations. Our findings provide new insights into the pathophysiology of LHON arising from the synergy between mitochondrial ND1 and ND4 mutations.
Collapse
Affiliation(s)
- Yanchun Ji
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Juanjuan Zhang
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jialing Yu
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Ying Wang
- Department of Ophthalmology, Chinese Academy of Traditional Chinese Medicine, Beijing, China
| | - Yuanyuan Lu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Min Liang
- Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Qiang Li
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xiaofen Jin
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yinsheng Wei
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Feilong Meng
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yinglong Gao
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xiaohui Cang
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yi Tong
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaoling Liu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Minglian Zhang
- Department of Ophthalmology, Hebei Provincial Eye Hospital, Xingtai, Hebei, China
| | - Peifang Jiang
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Tao Zhu
- Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jun Qin Mo
- Department of Pathology, Rady Children's Hospital, University of California School of Medicine, San Diego, California, USA
| | - Taosheng Huang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Pingping Jiang
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Min-Xin Guan
- Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Lab of Reproductive Genetics, Ministry of Education of PRC, Zhejiang University, Hangzhou, China.,Joint Institute of Genetics and Genomic Medicine between Zhejiang University and University of Toronto, Hangzhou, Zhejiang, China
| |
Collapse
|
10
|
Ding Y, Ye YF, Li MY, Xia BH, Leng JH. Mitochondrial tRNAAla 5601C>T variant may affect the clinical expression of the LHON‑related ND4 11778G>A mutation in a family. Mol Med Rep 2019; 21:201-208. [PMID: 31939618 PMCID: PMC6896293 DOI: 10.3892/mmr.2019.10844] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 10/09/2019] [Indexed: 01/21/2023] Open
Abstract
Certain mutations in mitochondrial DNA (mtDNA) are associated with Leber's hereditary optic neuropathy (LHON). In particular, the well-known NADH dehydrogenase 4 (ND4) m.11778G>A mutation is one of the most common LHON-associated primary mutations worldwide. However, how specific mtDNA mutations, or variants, affect LHON penetrance is not fully understood. The aim of the current study was to explore the relationship between mtDNA mutations and LHON, and to provide useful information for early detection and prevention of this disease. Following the molecular characterization of a Han Chinese family with maternally inherited LHON, four out of eight matrilineal relatives demonstrated varying degrees of both visual impairment and age of onset. Through PCR amplification of mitochondrial genomes and direct Sanger sequencing analysis, a homoplasmic mitochondrial-encoded ND4 m.11778G>A mutation, alongside a set of genetic variations belonging to human mtDNA haplogroup B5b1 were identified. Among these sequence variants, alanine transfer RNA (tRNA)Ala m.5601C>T was of particular interest. This variant occurred at position 59 in the TψC loop and altered the base pairing, which led to mitochondrial RNA (mt-RNA) metabolism failure and defects in mitochondrial protein synthesis. Bioinformatics analysis suggested that the m.5601C>T variant altered tRNAAla structure. Therefore, impaired mitochondrial functions caused by the ND4 m.11778G>A mutation may be enhanced by the mt-tRNAAla m.5601C>T variant. These findings suggested that the tRNAAla m.5601C>T variant might modulate the clinical manifestation of the LHON-associated primary mutation.
Collapse
Affiliation(s)
- Yu Ding
- Central Laboratory, School of Medicine, Hangzhou First People's Hospital, Zhejiang University, Hangzhou, Zhejiang 310006, P.R. China
| | - Yu-Feng Ye
- Department of Ophthalmology, School of Medicine, Hangzhou First People's Hospital, Zhejiang University, Hangzhou, Zhejiang 310006, P.R. China
| | - Mei-Ya Li
- Analytical Testing Center, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China
| | - Bo-Hou Xia
- Department of Pharmacy, Hunan Chinese Medical University, Changsha, Hunan 410208, P.R. China
| | - Jian-Hang Leng
- Central Laboratory, School of Medicine, Hangzhou First People's Hospital, Zhejiang University, Hangzhou, Zhejiang 310006, P.R. China
| |
Collapse
|
11
|
Lyu Y, Xu M, Chen J, Ji Y, Guan MX, Zhang J. Frequency and spectrum of MT-TT variants associated with Leber's hereditary optic neuropathy in a Chinese cohort of subjects. MITOCHONDRIAL DNA PART B-RESOURCES 2019; 4:2266-2280. [PMID: 33365504 PMCID: PMC7687527 DOI: 10.1080/23802359.2019.1627921] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Leber’s hereditary optic neuropathy (LHON) is a maternally inherited eye disease. In our previous investigations, we have reported the spectrum and frequency of mitochondrial MT-ND1, MT-ND4 and MT-ND6 gene in Chinese LHON population. This study aimed to assess the molecular epidemiology of MT-TT mutations in Chinese families with LHON. A cohort of 352 Chinese Han probands lacking the known LHON-associated mtDNA mutations and 376 control subjects underwent molecular analysis of mtDNA. All variants were evaluated for evolutionary conservation, structural and functional consequences. Fifteen variants were identified in the MT-TT gene by mitochondrial genome analysis of LHON pedigrees, which was substantially higher than that of individuals from general Chinese populations. The incidences of the two known LHON-associated mutations, m.15927G > A and m.15951A > G, were 2.27% and 1.14%, respectively. Nine putative LHON-associated variants were identified in 20 probands, translated into 2.1% cases of this cohort. Moreover, mtDNAs in 41 probands carrying the MT-TT mutation(s) were widely dispersed among nine Eastern Asian haplogroups. Our results suggest that the MT-TT gene is a mutational hotspot for these 352 Chinese families lacking the known LHON-associated mutations. These data further showed the molecular epidemiology of MT-TT mutations in Chinese Han LHON pedigrees.
Collapse
Affiliation(s)
- Yuanyuan Lyu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,School of Laboratory Medicine and Life Sciences, Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Man Xu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,School of Laboratory Medicine and Life Sciences, Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jie Chen
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,School of Laboratory Medicine and Life Sciences, Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - YanChun Ji
- School of Medicine, Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Min-Xin Guan
- School of Laboratory Medicine and Life Sciences, Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China.,School of Medicine, Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Juanjuan Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China.,School of Laboratory Medicine and Life Sciences, Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| |
Collapse
|
12
|
Abstract
SIGNIFICANCE We identified a missense mutation, m.11778G>A (p.R340H), in the mitochondrially encoded NADH dehydrogenase 4 gene (ND4) in eight patients and three asymptomatic carriers, even though the incidence of this has been considered low in Chinese population. These results have implications for the families' genetic counseling and clinical management. PURPOSE Leber hereditary optic neuropathy (LHON OMIM 535000) is one of the most common inherited optic neuropathies. The aim of this study was to identify the genetic cause in two Han Chinese families with LHON. METHODS We used Sanger sequencing to identify the genetic cause of two Han Chinese families from Hunan, China, with LHON. RESULTS The patients in these two families presented with typical LHON, with male patients experiencing more severe phenotypes. A missense mutation, m.11778G>A (p.R340H), in the ND4 gene was identified in eight patients and three asymptomatic carriers, even though the incidence of this has been considered low in Chinese population. CONCLUSIONS Eight of 11 family members (72.7%) manifested some vision loss, which is far higher percentage than reported in other studies. The variant is predicted to be the disease-causing mutation and results in seriously abnormal function of complex I subunits of the mitochondrial respiratory chain. These results have implications for the families' genetic counseling and clinical management and help to develop new LHON target-gene therapy strategies.
Collapse
|
13
|
Chen H, Sun M, Fan Z, Tong M, Chen G, Li D, Ye J, Yang Y, Zhu Y, Zhu J. Mitochondrial C4375T mutation might be a molecular risk factor in a maternal Chinese hypertensive family under haplotype C. Clin Exp Hypertens 2017; 40:518-523. [PMID: 29200319 DOI: 10.1080/10641963.2017.1403622] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Here, we reported a Han Chinese essential hypertensive pedigree based on clinical hereditary and molecular data. To know the molecular basis on this family, mitochondrial genome of one proband from the family was identified through direct sequencing analysis. The age of onset year and affected degree of patients are different in this family. And matrilineal family members carrying C4375T mutation and belong to Eastern Asian halopgroup C. Phylogenetic analysis shows 4375C is highly conservative in 17 species. It is suggested that these mutations might participate in the development of hypertension in this family. And halopgroup C might play a modifying role on the phenotype in this Chinese hypertensive family.
Collapse
Affiliation(s)
- Hong Chen
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Min Sun
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Zhen Fan
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Maoqing Tong
- c Department of Cardiology , Ningbo First Hospital, Ningbo, China.,d Key Laboratory of Molecular Medicine , Ningbo First Hospital , Ningbo , Zhejiang P.R. China
| | - Guodong Chen
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Danhui Li
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Jihui Ye
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Yumin Yang
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Yongding Zhu
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| | - Jianhua Zhu
- a Intensive Care Unit , Ningbo First Hospital, Ningbo, China.,b Intensive Care Unit , Ningbo Hospital of Zhejiang University, Ningbo, China
| |
Collapse
|
14
|
Lv ZY, Xu XM, Cao XF, Wang Q, Sun DF, Tian WJ, Yang Y, Wang YZ, Hao YL. Mitochondrial mutations in 12S rRNA and 16S rRNA presenting as chronic progressive external ophthalmoplegia (CPEO) plus: A case report. Medicine (Baltimore) 2017; 96:e8869. [PMID: 29310369 PMCID: PMC5728770 DOI: 10.1097/md.0000000000008869] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
RATIONALE Chronic progressive external ophthalmoplegia (CPEO) is a classical mitochondrial ocular disorder characterized by bilateral progressive ptosis and ophthalmoplegia. Kearns -Sayre syndrome (KSS) is a multisystem disorder with PEO, cardiac conduction block, and pigmentary retinopathy. A few individuals with CPEO have other manifestations of KSS, but do not meet all the clinical diagnosis criteria, and this is called "CPEO plus." PATIENT CONCERNS We report a 48-year-old woman exhibiting limb weakness, ptosis, ophthalmoparesis, and cerebellar dysfunctions. DIAGNOSES The patient was diagnosed as exhibiting CPEO plus syndrome. INTERVENTIONS The patient underwent clinical, genetic, histological, and histochemical analysis. She was treated orally with CoQ10, vitamin Bs, L-carnitine, and vitamin E. OUTCOMES The patient's serum creatine kinase levels, electrocardiography, and nerve conduction study results were normal; an electromyogram revealed myopathic findings. Magnetic resonance imaging showed global brain atrophy, particularly in the brainstem and cerebellum areas. A muscle biopsy showed the presence of abundant ragged red fibers. Sequencing of the mitochondrial DNA from the skeletal muscle biopsy revealed C960del mutation in 12S rRNA and homozygous mutation C2835T in 16S rRNA. She took medicines on schedule, the clinical features were similar as 2 years ago. LESSONS This is the first report of 2 rRNA mutations in a patient with MRI findings showing global brain atrophy, particularly in brainstem and cerebellum areas. Early recognition and appropriate treatment is crucial. This case highlights the cerebellar ataxia can occur in CPEO plus.
Collapse
|
15
|
Manickam AH, Michael MJ, Ramasamy S. Mitochondrial genetics and therapeutic overview of Leber's hereditary optic neuropathy. Indian J Ophthalmol 2017; 65:1087-1092. [PMID: 29133631 PMCID: PMC5700573 DOI: 10.4103/ijo.ijo_358_17] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/09/2017] [Indexed: 12/22/2022] Open
Abstract
Leber's hereditary optic neuropathy (LHON) is a common inherited mitochondrial disorder that is characterized by the degeneration of the optic nerves, leading to vision loss. The major mutations in the mitochondrial genes ND1, ND4, and ND6 of LHON subjects are found to increase the oxidative stress experienced by the optic nerve cell, thereby leading to nerve cell damage. Accurate treatments are not available and drugs that are commercially available like Idebenone, EPI-743, and Bendavia with their antioxidant role help in reducing the oxidative stress experienced by the cell thereby preventing the progression of the disease. Genetic counseling plays an effective role in making the family members aware of the inheritance pattern of the disease. Gene therapy is an alternative for curing the disease but is still under study. This review focuses on the role of mitochondrial genes in causing LHON and therapeutics available for treating the disease. A systematic search has been adopted in various databases using the keywords "LHON," "mitochondria," "ND1," "ND4," "ND6," and "therapy" and the following review on mitochondrial genetics and therapeutics of LHON has been developed with obtained articles from 1988 to 2017.
Collapse
Affiliation(s)
- Agaath Hedina Manickam
- Molecular Genetics and Cancer Biology Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore, Tami Nadu, India
| | - Minu Jenifer Michael
- Molecular Genetics and Cancer Biology Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore, Tami Nadu, India
| | - Sivasamy Ramasamy
- Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore, Tami Nadu, India
| |
Collapse
|
16
|
Ji Y, Qiao L, Liang X, Zhu L, Gao Y, Zhang J, Jia Z, Wei QP, Liu X, Jiang P, Guan MX. Leber's hereditary optic neuropathy is potentially associated with a novel m.5587T>C mutation in two pedigrees. Mol Med Rep 2017; 16:8997-9004. [PMID: 28990081 DOI: 10.3892/mmr.2017.7734] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 07/21/2017] [Indexed: 12/17/2022] Open
Abstract
Mitochondrial (mt)DNA mutations have been revealed to be associated with Leber's hereditary optic neuropathy (LHON). The present study conducted clinical, genetic and molecular evaluations of two Han Chinese families. A total of 4 (3 men and 1 female) out of 14 matrilineal relatives in the families exhibited visual impairment with variable severity and age of onset. The average age of onset of visual loss was 20.5 years old. Molecular analysis of the complete mitochondrial genome in these pedigrees demonstrated that the three primary mutations associated with LHON were not detected; however, the homoplasmic m.5587T>C mutation was identified, which was localized at the end of the mitochondrially encoded transfer (t)RNA alanine gene and may alter the tertiary structure of this tRNA. Subsequently, this structural alteration may result in tRNA metabolism failure. In addition, distinct sets of mtDNA polymorphisms belonging to haplogroup F1 were detected in both families tested. The findings of the present study suggested that the m.5587T>C mutation may be involved in the pathogenesis of visual impairment. In addition, the mtDNA variant m.15024G>A(p.C93H) in the mitochondrially encoded cytochrome B gene was detected in both families, which exhibited evolutionary conservation, indicating it may serve a potential modifying role in the development of visual impairment associated with m.5587T>C mutation in these families. Furthermore, other modifying factors, including nuclear modifier genes, and environmental and personal factors may also contribute to the development of LHON in subjects carrying this mutation.
Collapse
Affiliation(s)
- Yanchun Ji
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| | - Lihua Qiao
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| | - Xiaoyang Liang
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| | - Ling Zhu
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| | - Yinglong Gao
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| | - Juanjuan Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang 325025, P.R. China
| | - Zidong Jia
- Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| | - Qi-Ping Wei
- Department of Ophthalmology, Beijing University of Chinese Medicine, Beijing 100029, P.R. China
| | - Xiaoling Liu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang 325025, P.R. China
| | - Pingping Jiang
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| | - Min-Xin Guan
- Division of Clinical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, P.R. China
| |
Collapse
|
17
|
Caporali L, Maresca A, Capristo M, Del Dotto V, Tagliavini F, Valentino ML, La Morgia C, Carelli V. Incomplete penetrance in mitochondrial optic neuropathies. Mitochondrion 2017; 36:130-137. [PMID: 28716668 DOI: 10.1016/j.mito.2017.07.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 06/27/2017] [Accepted: 07/13/2017] [Indexed: 01/06/2023]
Abstract
Incomplete penetrance characterizes the two most frequent inherited optic neuropathies, Leber's Hereditary Optic Neuropathy (LHON) and dominant optic atrophy (DOA), due to genetic errors in the mitochondrial DNA (mtDNA) and the nuclear DNA (nDNA), respectively. For LHON, compelling evidence has accumulated on the complex interplay of mtDNA haplogroups and environmental interacting factors, whereas the nDNA remains essentially non informative. However, a compensatory mechanism of activated mitochondrial biogenesis and increased mtDNA copy number, possibly driven by a permissive nDNA background, is documented in LHON; when successful it maintains unaffected the mutation carriers, but in some individuals it might be hampered by tobacco smoking or other environmental factors, resulting in disease onset. In females, mitochondrial biogenesis is promoted and maintained within the compensatory range by estrogens, partially explaining the gender bias in LHON. Concerning DOA, none of the above mechanisms has been fully explored, thus mtDNA haplogroups, environmental factors such as tobacco and alcohol, and further nDNA variants may all participate as protective factors or, on the contrary, favor disease expression and severity. Next generation sequencing, complemented by transcriptomics and proteomics, may provide some answers in the next future, even if the multifactorial model that seems to apply to incomplete penetrance in mitochondrial optic neuropathies remains problematic, and careful stratification of patients will play a key role for data interpretation. The deep understanding of which factors impinge on incomplete penetrance may shed light on the pathogenic mechanisms leading to optic nerve atrophy, on their possible compensation and, thus, on development of therapeutic strategies.
Collapse
Affiliation(s)
- Leonardo Caporali
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy
| | - Alessandra Maresca
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy
| | | | - Valentina Del Dotto
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Francesca Tagliavini
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy
| | - Maria Lucia Valentino
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Chiara La Morgia
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Valerio Carelli
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy.
| |
Collapse
|
18
|
Jiang P, Liang M, Zhang C, Zhao X, He Q, Cui L, Liu X, Sun YH, Fu Q, Ji Y, Bai Y, Huang T, Guan MX. Biochemical evidence for a mitochondrial genetic modifier in the phenotypic manifestation of Leber's hereditary optic neuropathy-associated mitochondrial DNA mutation. Hum Mol Genet 2016; 25:3613-3625. [PMID: 27427386 DOI: 10.1093/hmg/ddw199] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 06/08/2016] [Accepted: 06/21/2016] [Indexed: 02/01/2023] Open
Abstract
Leber's hereditary optic neuropathy (LHON) is the most common mitochondrial disease. Mitochondrial modifiers are proposed to modify the phenotypic expression of primary LHON-associated mitochondrial DNA (mtDNA) mutations. In this study, we demonstrated that the LHON susceptibility allele (m.14502T > C, p. 58I > V) in the ND6 gene modulated the phenotypic expression of primary LHON-associated m.11778G > A mutation. Twenty-two Han Chinese pedigrees carrying m.14502T > C and m.11778G > A mutations exhibited significantly higher penetrance of optic neuropathy than those carrying only m.11778G > A mutation. We performed functional assays using the cybrid cell models, generated by fusing mtDNA-less ρo cells with enucleated cells from LHON patients carrying both m.11778G > A and m.14502T > C mutations, only m.14502T > C or m.11778G > A mutation and a control belonging to the same mtDNA haplogroup. These cybrids cell lines bearing m.14502T > C mutation exhibited mild effects on mitochondrial functions compared with those carrying only m.11778G > A mutation. However, more severe mitochondrial dysfunctions were observed in cell lines bearing both m.14502T > C and m.11778G > A mutations than those carrying only m.11778G > A or m.14502T > C mutation. In particular, the m.14502T > C mutation altered assemble of complex I, thereby aggravating the respiratory phenotypes associated with m.11778G > A mutation, resulted in a more defective complex I. Furthermore, more reductions in the levels of mitochondrial ATP and increasing production of reactive oxygen species were also observed in mutant cells bearing both m.14502T > C and m.11778G > A mutation than those carrying only 11778G > A mutation. Our findings provided new insights into the pathophysiology of LHON that were manifested by interaction between primary and secondary mtDNA mutations.
Collapse
Affiliation(s)
- Pingping Jiang
- Divsion of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China.,Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Min Liang
- Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Department of Clinical Laboratory, The First Affiliated Hospital.,School of Ophthalmology and Optometry
| | - Chaofan Zhang
- Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Xiaoxu Zhao
- Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Qiufen He
- Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Limei Cui
- Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Xiaoling Liu
- School of Ophthalmology and Optometry.,Attardi Institute of Mitochondrial Biomedicine, School of Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Yan-Hong Sun
- Department of Ophthalmology, Beijing University of Chinese Medicine and Pharmacology, Beijing 100029, China
| | - Qun Fu
- Department of Ophthalmology, The Third Affiliated Hospital, Xinxiang Medical College, Xinxiang, Henan 45300, China
| | - Yanchun Ji
- Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Yidong Bai
- Department of Cellular & Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Taosheng Huang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, OH 45229, USA
| | - Min-Xin Guan
- Divsion of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China .,Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Joining Institute of Genetics and Genomic Medicine between Zhejiang University and University of Toronto, Hangzhou, Zhejiang 310058, China
| |
Collapse
|
19
|
Xie S, Zhang J, Sun J, Zhang M, Zhao F, Wei QP, Tong Y, Liu X, Zhou X, Jiang P, Ji Y, Guan MX. Mitochondrial haplogroup D4j specific variant m.11696G > a(MT-ND4) may increase the penetrance and expressivity of the LHON-associated m.11778G > a mutation in Chinese pedigrees. Mitochondrial DNA A DNA Mapp Seq Anal 2016; 28:434-441. [PMID: 27159682 DOI: 10.3109/19401736.2015.1136304] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Leber's hereditary optic neuropathy (LHON) is one of the most common mitochondrial disorders. We report here the clinical, genetic and molecular analysis of mitochondrial DNA (mtDNA) in eight Han Chinese families carrying the known mitochondrial 11778G > A(MT-ND4) mutation. Thirty-seven (26 males/11 females) of 77 matrilineal relatives in these families exhibited the variable severity and age-at-onset of optic neuropathy. The penetrances were from 25% to 75%, with the average of 42%, and the age-at-onset for visual impairment varied from 10 to 25 years, with the average of 17 in these Chinese pedigrees. Molecular analysis of their mtDNA identified distinct sets of variants belonging to the Eastern Asian haplogroupD4j. Except the known m.11778G > A mutation, the m.11696G > A(MT-ND4) mutation caused the substitution of an isoleucine for valineat amino acid position 313, located in a predicted transmembrane region of ND4. And, it is reported that the m.11696G > A mutation was associated with LHON, and appeared to contribute to higher penetrance in these nine Chinese families than other Chinese families carrying only the m.11778G > A mutation. Therefore, the mitochondrial haplogroup D4j specific m.11696G > A mutation may act in synergy with the primary LHON-associated m.11778G > A mutation, thereby increasing the penetrance and expressivity of visual loss in these Chinese families.
Collapse
Affiliation(s)
- Shipeng Xie
- a Department of Ophthalmology , Xingtai Eye Hospital , Xingtai , Hebei , China
| | - Juanjuan Zhang
- b Institute of Genetics , Zhejiang University School of Medicine , Hangzhou , Zhejiang , China.,c School of Ophthalmology and Optometry , Wenzhou Medical University , Wenzhou , Zhejiang , China
| | - Jiji Sun
- b Institute of Genetics , Zhejiang University School of Medicine , Hangzhou , Zhejiang , China
| | - Minglian Zhang
- a Department of Ophthalmology , Xingtai Eye Hospital , Xingtai , Hebei , China
| | - Fuxin Zhao
- c School of Ophthalmology and Optometry , Wenzhou Medical University , Wenzhou , Zhejiang , China.,d Attardi Institute of Mitochondrial Biomedicine , Wenzhou Medical University , Wenzhou , Zhejiang , China
| | - Qi-Ping Wei
- e Department of Ophthalmology , Dongfang Hospital, Beijing University of Chinese Medicine and Pharmacology , Beijing , China
| | - Yi Tong
- c School of Ophthalmology and Optometry , Wenzhou Medical University , Wenzhou , Zhejiang , China
| | - Xiaoling Liu
- c School of Ophthalmology and Optometry , Wenzhou Medical University , Wenzhou , Zhejiang , China
| | - Xiangtian Zhou
- c School of Ophthalmology and Optometry , Wenzhou Medical University , Wenzhou , Zhejiang , China
| | - Pingping Jiang
- b Institute of Genetics , Zhejiang University School of Medicine , Hangzhou , Zhejiang , China.,f Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases , Zhejiang University , Hangzhou , China
| | - Yanchun Ji
- b Institute of Genetics , Zhejiang University School of Medicine , Hangzhou , Zhejiang , China
| | - Min-Xin Guan
- a Department of Ophthalmology , Xingtai Eye Hospital , Xingtai , Hebei , China.,f Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases , Zhejiang University , Hangzhou , China.,g Division of Pathology , Cincinnati Children's Hospital Medical Center , Cincinnati , OH , USA
| |
Collapse
|
20
|
Wang L, Chen ZJ, Zhang YK, Le HB. The role of mitochondrial tRNA mutations in lung cancer. Int J Clin Exp Med 2015; 8:13341-13346. [PMID: 26550263 PMCID: PMC4612948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 06/23/2015] [Indexed: 06/05/2023]
Abstract
Alternations in mitochondrial genome resulting in mitochondrial dysfunction have long been hypothesized to be involved in tumorigenesis. Mitochondrial tRNA (mt-tRNA) is known for its high frequencies of polymorphisms and mutations, however, the roles of these mutations and polymorphisms in lung cancer are among heated debates. To evaluate the possible roles of reported mt-tRNA mutations in lung cancer, we examine recent published paper concerning three mt-tRNA mutations with lung cancer: A7460G in tRNA(Ser (UCN)) gene, G5563A in tRNA(Trp) gene and A12172G in tRNA(His) gene. We perform the phylogenetic approach to investigate the deleterious roles of these mutations in lung cancer, moreover, we use bioinformatics tool to predict the secondary structure of mt-tRNAs with and without these mutations. In addition, through the application of pathogenicity scoring system, we find that only the A12172G mutation is regarded as a pathogenic mutation, whereas other mutations may act as neutral polymorphisms in human population. Thus, our study provides the novel insight into the molecular pathogenesis of mt-tRNA mutations in lung cancer.
Collapse
Affiliation(s)
- Lie Wang
- Department of Cardiothoracic Surgery, Zhou Shan Hospital Zhou Shan, Zhejiang, China
| | - Zhi-Jun Chen
- Department of Cardiothoracic Surgery, Zhou Shan Hospital Zhou Shan, Zhejiang, China
| | - Yong-Kui Zhang
- Department of Cardiothoracic Surgery, Zhou Shan Hospital Zhou Shan, Zhejiang, China
| | - Han-Bo Le
- Department of Cardiothoracic Surgery, Zhou Shan Hospital Zhou Shan, Zhejiang, China
| |
Collapse
|
21
|
QIAO CHEN, WEI TANWEI, HU BO, PENG CHUNYAN, QIU XUEPING, WEI LI, YAN MING. Two families with Leber’s hereditary optic neuropathy carrying G11778A and T14502C mutations with haplogroup H2a2a1 in mitochondrial DNA. Mol Med Rep 2015; 12:3067-72. [DOI: 10.3892/mmr.2015.3714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Accepted: 03/18/2015] [Indexed: 11/06/2022] Open
|
22
|
Zhang J, Jiang P, Jin X, Liu X, Zhang M, Xie S, Gao M, Zhang S, Sun YH, Zhu J, Ji Y, Wei QP, Tong Y, Guan MX. Leber's hereditary optic neuropathy caused by the homoplasmic ND1 m.3635G>A mutation in nine Han Chinese families. Mitochondrion 2014; 18:18-26. [PMID: 25194554 DOI: 10.1016/j.mito.2014.08.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 08/28/2014] [Accepted: 08/29/2014] [Indexed: 11/18/2022]
Abstract
In this report, we investigated the molecular mechanism underlying Leber's hereditary optic neuropathy (LHON)-associated mitochondrial m.3635G>A (p.S110N, ND1) mutation. A mutational screening of ND1 gene in a cohort of 1070 Han Chinese subjects LHON identified the m.3635G>A mutation in nine Chinese families with suggestively maternally transmitted LHON. Thirty-eight (22 males/16 females) of 162 matrilineal relatives in these families exhibited the variable severity and age-at-onset of optic neuropathy. Molecular analysis of their mitochondrial genomes identified the homoplasmic m.3635G>A mutation and distinct sets of polymorphisms belonging to the Asian haplogroups G2a1, R11a, D4, R11a, M7b2, G1a, F1a1, B4, and N9a3, respectively. Using cybrids constructed by transferring mitochondria from lymphoblastoid cell lines derived from one Chinese family into mtDNA-less (ρ(0)) cells, we showed ~27% decrease in the activity of NADH:ubiquinone oxidoreductase (complex I) in mutant cybrids carrying the m.3635G>A mutation, compared with control cybrids. The respiratory deficiency caused by the m.3635G>A mutation results in decreased efficiency of mitochondrial ATP synthesis. These mitochondrial dysfunctions caused an increase in the production of reactive oxygen species in the mutant cybrids. The data provide the direct evidence for the m.3635G>A mutation leading to LHON. Our findings may provide new insights into the understanding of pathophysiology of LHON.
Collapse
Affiliation(s)
- Juanjuan Zhang
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China; School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Pingping Jiang
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiaofen Jin
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiaoling Liu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China; Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Minglian Zhang
- Department of Ophthalmology, Hebei Provincial Eye Hospital, Xingtai, Hebei, China
| | - Shipeng Xie
- Department of Ophthalmology, Hebei Provincial Eye Hospital, Xingtai, Hebei, China
| | - Min Gao
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China; Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Sai Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China; Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yan-Hong Sun
- Department of Ophthalmology, Beijing University of Chinese Medicine and Pharmacology, Beijing, China
| | - Jinping Zhu
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China; Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yanchun Ji
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Qi-Ping Wei
- Department of Ophthalmology, Beijing University of Chinese Medicine and Pharmacology, Beijing, China
| | - Yi Tong
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Min-Xin Guan
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China; Attardi Institute of Mitochondrial Biomedicine, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| |
Collapse
|
23
|
Pei H, Peng Q, Lan C, Chi Liu B. Variations in mitochondrial tRNAThrgene may not be associated with coronary heart disease. ACTA ACUST UNITED AC 2014; 27:565-8. [DOI: 10.3109/19401736.2014.905862] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
24
|
Zhou X, Qian Y, Zhang J, Tong Y, Jiang P, Liang M, Dai X, Zhou H, Zhao F, Ji Y, Mo JQ, Qu J, Guan MX. Leber's hereditary optic neuropathy is associated with the T3866C mutation in mitochondrial ND1 gene in three Han Chinese Families. Invest Ophthalmol Vis Sci 2012; 53:4586-94. [PMID: 22577081 DOI: 10.1167/iovs.11-9109] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To investigate the pathophysiology of Leber's hereditary optic neuropathy (LHON). METHODS Seventy-one subjects from three Chinese families with LHON underwent clinical, genetic, molecular, and biochemical evaluations. Biochemical characterizations included the measurements of the rates of endogenous, substrate-dependent respirations, the adenosine triphosphate (ATP) production and generation of reactive oxygen species using lymphoblastoid cell lines derived from five affected matrilineal relatives of these families and three control subjects. RESULTS Ten of 41 matrilineal relatives exhibited variable severity and age at onset of optic neuropathy. The average age at onset of optic neuropathy in matrilineal relatives of the three families was 5, 11, and 24 years, respectively. Molecular analysis identified the ND1 T3866C (I187T) mutation and distinct sets of polymorphisms belonging to the Eastern Asian haplogroups D4a, M10a, and R, respectively. The I187T mutation is localized at the highly conserved isoleucine at a transmembrane domain of the ND1 polypeptide. The marked reductions in the rate of endogenous, malate/glutamate-promoted and succinate/glycerol-3-phosphate-promoted respiration were observed in mutant cell lines carrying the T3866C mutation. The deficient respiration is responsible for the reduced ATP synthesis and increased generation of reactive oxygen species. CONCLUSIONS Our data convincingly show that the ND1 T3866C mutation leads to LHON. This mutation may be insufficient to produce a clinical phenotype. Other modifier factors may contribute to the phenotypic manifestation of the T3866C mutation. The T3866C mutation should be added to the list of inherited factors for molecular diagnosis of LHON. Thus, our findings may provide new insights into the understanding of pathophysiology and valuable information on the management of LHON.
Collapse
Affiliation(s)
- Xiangtian Zhou
- School of Ophthalmology and Optometry, Wenzhou Medical College, Zhejiang, China
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Shu L, Zhang YM, Huang XX, Chen CY, Zhang XN. Complete mitochondrial DNA sequence analysis in two southern Chinese pedigrees with Leber hereditary optic neuropathy revealed secondary mutations along with the primary mutation. Int J Ophthalmol 2012; 5:28-31. [PMID: 22553750 DOI: 10.3980/j.issn.2222-3959.2012.01.06] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 01/10/2012] [Indexed: 11/02/2022] Open
Abstract
AIM To investigate mitochondrial factors associated with Leber hereditary optic neuropathy (LHON) through complete sequencing and analysis of the mitochondrial genome of Chinese patients with this disease. METHODS Two unrelated southern Chinese families with LHON and 10 matched healthy controls were recruited, and their entire mitochondrial DNA (mtDNA) was amplified and sequenced with the universal M13 primer. Then DNA sequence analysis and variation identification were perfomed by DNAssist and Chromas 2 software and compared with authoritative databases such as Mitomap. RESULTS Mutational analysis of mtDNA in these two Chinese pedigrees revealed one common LHON-associated mutation, G11778A (Arg→His), in the MT-ND4 gene. In addition, there were two secondary mutations in Pedigree 1: C3497T (Ala→Val), and C3571T (Leu→Phe) in the MT-ND1 gene, which have not been reported; and two secondary mutations occurred in Pedigree 2: A10398G (Thr→Ala) in the MT-ND3 gene, and T14502C (Ile→Val) in the MT-ND6 gene. Three polymorphisms, A73G, G94A and A263G in the mtDNA control region, were also found. CONCLUSION Our study confirmed that the known MT-ND4*G11778A mutation is the most significant cause of LHON. The C3497T and C3571T mutations in Pedigree 1 were also both at hot-spots of MT-ND1; they may affect the respiratory chain in coordination with the primary mutation G11778A. In Pedigree 2, the two secondary mutations A10398G of MT-ND3 and T14502C of MT-ND6 may influence mitochondrial respiratory complex I, leading to the mitochondrial respiratory chain dysfunction which results in optic atrophy together with G11778A. Therefore, not only the common primary LHON mutation is responsible for the visual atrophy, but other secondary mtDNA mutations should also be considered when giving genetic counseling.
Collapse
Affiliation(s)
- Lei Shu
- Hangzhou Red Cross Hospital, Hangzhou 310003, Zhejiang Province, China
| | | | | | | | | |
Collapse
|
26
|
Qian Y, Zhou X, Liang M, Qu J, Guan MX. The altered activity of complex III may contribute to the high penetrance of Leber's hereditary optic neuropathy in a Chinese family carrying the ND4 G11778A mutation. Mitochondrion 2011; 11:871-7. [PMID: 21742061 DOI: 10.1016/j.mito.2011.06.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 05/13/2011] [Accepted: 06/24/2011] [Indexed: 02/07/2023]
Abstract
The ND4 G11778A mutation is the most common mitochondrial DNA mutation leading to Leber's hereditary optic neuropathy (LHON). Despite considerable clinical evidences, the modifier role of nuclear background and mitochondrial haplotypes in phenotypic manifestation of LHON remains poorly understood. We investigated the effect of these modifiers on bioenergetics in lymphoblastoid cell lines derived from five affected subjects of one Chinese family carrying the G11778A mutation and five Chinese controls. Significant reductions in the activities of complexes I and III were observed in mutant cell lines from the Chinese family, whereas the mutant cell lines from other families carrying the same mutation exhibited only reduced activity of complex I. The reduced activities of complexes I and III caused remarkably higher reductions of ATP synthesis in mutant cell lines from the Chinese family than those from other families. The deficient respiration increased generation of reactive oxygen species. The defect in complex III activity, likely resulting from the mitochondrial haplotype or nuclear gene alteration, worsens mitochondrial dysfunction caused by the G11778A mutation, thereby causing extremely high penetrance and expressivity of optic neuropathy in this Chinese family. Our data provide the first experimental evidence that altered activity of complex III modulates the phenotypic manifestation of LHON-associated G11778A mutation. Thus, our findings may provide new insights into the pathophysiology of LHON.
Collapse
Affiliation(s)
- Yaping Qian
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | | | | | | | | |
Collapse
|
27
|
The tRNAMet 4435A>G mutation in the mitochondrial haplogroup G2a1 is responsible for maternally inherited hypertension in a Chinese pedigree. Eur J Hum Genet 2011; 19:1181-6. [PMID: 21694735 PMCID: PMC3198143 DOI: 10.1038/ejhg.2011.111] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mutations in mitochondrial DNA (mtDNA) have been associated with hypertension in several pedigrees with maternal inheritance. However, the pathophysiology of maternally inherited hypertension remains poorly understood. We reported here clinical, genetic evaluations and molecular analysis of mtDNA in a three-generation Han Chinese family with essential hypertension. Eight of 17 matrilineal relatives exhibited a wide range of severity in essential hypertension, whereas none of the offsprings of the affected father had hypertension. The age-at-onset of hypertension in the maternal kindred varied from 31 to 65 years, with an average of 52 years. Sequence analysis of mtDNA in this pedigree identified the known homoplasmic 4435A>G mutation, which is located at immediately 3' end to the anticodon, corresponding to the conventional position 37 of tRNA(Met), and 41 variants belonging to the Asian haplogroup G2a1. In contrast, the 4435A>G mutation occurred among mtDNA haplogroups B5a, D, M7a2 and J. The adenine (A37) at this position of tRNA(Met) is extraordinarily conserved from bacteria to human mitochondria. This modified A37 was shown to contribute to the high fidelity of codon recognition, structural formation and stabilization of functional tRNAs. However, 41 other mtDNA variants in this pedigree were the known polymorphisms. The occurrence of the 4435A>G mutation in two genetically unrelated families affected by hypertension indicates that this mutation is involved in hypertension. Our present investigations further supported our previous findings that the 4435A>G mutation acted as an inherited risk factor for the development of hypertension. Our findings will be helpful for counseling families of maternally inherited hypertension.
Collapse
|
28
|
Wang S, Li R, Fettermann A, Li Z, Qian Y, Liu Y, Wang X, Zhou A, Mo JQ, Yang L, Jiang P, Taschner A, Rossmanith W, Guan MX. Maternally inherited essential hypertension is associated with the novel 4263A>G mutation in the mitochondrial tRNAIle gene in a large Han Chinese family. Circ Res 2011; 108:862-70. [PMID: 21454794 DOI: 10.1161/circresaha.110.231811] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
RATIONALE Despite maternal transmission of hypertension in some pedigrees, pathophysiology of maternally inherited hypertension remains poorly understood. OBJECTIVE To establish a causative link between mitochondrial dysfunction and essential hypertension. METHOD AND RESULTS A total of 106 subjects from a large Chinese family underwent clinical, genetic, molecular, and biochemical evaluations. Fifteen of 24 adult matrilineal relatives exhibited a wide range of severity in essential hypertension, whereas none of the offspring of affected fathers had hypertension. The age at onset of hypertension in the maternal kindred varied from 20 years to 69 years, with an average of 44 years. Mutational analysis of their mitochondrial genomes identified a novel homoplasmic 4263A>G mutation located at the processing site for the tRNA(Ile) 5'-end precursor. An in vitro processing analysis showed that the 4263A>G mutation reduced the efficiency of the tRNA(Ile) precursor 5'-end cleavage catalyzed by RNase P. tRNA Northern analysis revealed that the 4263A>G mutation caused ≈46% reduction in the steady-state level of tRNA(Ile). An in vivo protein-labeling analysis showed ≈32% reduction in the rate of mitochondrial translation in cells carrying the 4263A>G mutation. Impaired mitochondrial translation is apparently a primary contributor to the reductions in the rate of overall respiratory capacity, malate/glutamate-promoted respiration, succinate/glycerol-3-phosphate-promoted respiration, or N,N,N',N'-tetramethyl-p-phenylenediamine/ascorbate-promoted respiration and the increasing level of reactive oxygen species in cells carrying the 4263A>G mutation. CONCLUSIONS These data provide direct evidence that mitochondrial dysfunction caused by mitochondrial tRNA(Ile) 4263A>G mutation is involved in essential hypertension. Our findings may provide new insights into pathophysiology of maternally transmitted hypertension.
Collapse
Affiliation(s)
- Shiwen Wang
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang, China.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
[The mitochondrial ND5 T12338C mutation may be associated with Leber's hereditary optic neuropathy in two Chinese families]. YI CHUAN = HEREDITAS 2011; 33:322-8. [PMID: 21482521 DOI: 10.3724/sp.j.1005.2011.00322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Leber's hereditary optic neuropathy (LHON) associated with mitochondrial DNA mutation is a maternally inherited eye disease. We reported here the clinical, genetic and molecular characterization of two Han Chinese families with Leber's hereditary optic neuropathy. Ophthalmologic examinations revealed that the variable severity and age-of-onset in visual impairment among probands and other matrilineal relatives of these families. Strikingly, there were extremely low penetrances of visual impairment in these families. Sequence analysis of complete mitochondrial genomes in these pedigrees identified the homoplasmic ND4 G11696A and ND5 T12338C mutation and distinct sets of polymorphism belonging to haplogroups F2. It is well known that mitochondrial DNA ND4 G11696A is associated with LHON. The ND5 T12338C mutation resulted in replacement of the first amino acid, translation-initiating methionine with a threonine, and shortening two amino acids of ND5. This mutation also locates in two nucleotides adjacent to the 3' end of the tRNALeu(Cun). Thus, this mutation may alter structural formation and stabilization of functional tRNA, thereby leading to a failure in protein synthesis and mitochondrial dysfunction involved in visual impairment. Therefore, the ND4 G11696A and ND5 T12338C mutation is likely associated with LHON in these two Chinese families. But these families exhibited extremely low penetrances of visual impairment. It suggests that other factors, such as nuclear modifier gene(s) or environmental factor(s), may play a role in the phenotypic expression of the LHON-associated ND4 G11696A and ND5 T12338C mutation.
Collapse
|
30
|
Leber's hereditary optic neuropathy is associated with the T12338C mutation in mitochondrial ND5 gene in six Han Chinese families. Ophthalmology 2010; 118:978-85. [PMID: 21131053 DOI: 10.1016/j.ophtha.2010.09.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 09/08/2010] [Accepted: 09/08/2010] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To investigate the molecular pathogenesis of Leber's hereditary optic neuropathy (LHON) in Chinese families. DESIGN Six Han Chinese families who seem to have maternally transmitted LHON were studied by clinical, genetic, and molecular evaluations. PARTICIPANTS One hundred twenty-seven subjects from 6 Chinese families with a wide range of age-at-onset and severity of visual impairment. METHODS All subjects underwent clinical examination, genetic evaluation, and molecular analysis of mitochondrial DNA (mtDNA). MAIN OUTCOME MEASURES The ophthalmologic examinations included visual acuity, visual field examination, visual evoked potentials, and fundus photography. The mtDNA analysis included the polymerase chain reaction (PCR) amplification of entire mtDNA and subsequent sequence determination. RESULTS Six families exhibited low penetrance of visual impairment, with an average of 10.8%. In particular, 9 (6 males/3 females) of 86 matrilineal relatives in these families exhibited variable severity and age at onset in visual dysfunction. The average age at onset of visual loss was 20 years. Molecular analysis of mtDNA in these families identified the homoplasmic ND5T12338C mutation and distinct set of variants belonging to the Asian haplogroup F2. The T12338C mutation is only present in the maternal lineage of those pedigrees and not in 178 Chinese controls. This mutation resulted in the replacement of the first amino acid, a translation-initiating methionine with a threonine, shortening 2 amino acids of ND5 polypeptide. The T12338C mutation is also located in 2 nucleotides adjacent to the 3' end of the tRNA(Leu(CUN)). Thus, this mutation may alter ND5 mRNA metabolism and the processing of RNA precursors. As a result, this mutation impairs respiratory function, leading to visual impairment. CONCLUSIONS Several lines of evidence suggest that the mitochondrial ND5T12338C mutation is associated with LHON. The tissue specificity of this mutation is likely due to the involvement of nuclear modifier genes. The identification of nuclear modifiers is important for the elucidation of the pathogenic mechanism of LHON and an open avenue for therapeutic interventions. The T12338C mutation should be added to the list of inherited risk factors for future molecular diagnosis. Our findings are helpful for counseling families with LHON.
Collapse
|
31
|
Zhang M, Zhou X, Li C, Zhao F, Zhang J, Yuan M, Sun YH, Wang J, Tong Y, Liang M, Yang L, Cai W, Wang L, Qu J, Guan MX. Mitochondrial haplogroup M9a specific variant ND1 T3394C may have a modifying role in the phenotypic expression of the LHON-associated ND4 G11778A mutation. Mol Genet Metab 2010; 101:192-9. [PMID: 20728388 DOI: 10.1016/j.ymgme.2010.07.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 07/26/2010] [Indexed: 11/18/2022]
Abstract
We report here the clinical, genetic and molecular characterization of four Han Chinese families with Leber's hereditary optic neuropathy (LHON). The penetrances of optic neuropathy in these Chinese pedigrees were 38%, 38%, 44% and 56%. This observation is in contrast with the previously identified 14 Chinese families with very low penetrance of LHON. The age-at-onset for visual impairment in matrilineal relatives in these Chinese families varied from 18 to 30years. Furthermore, the ratios between affected male and female matrilineal relatives in these families were 3:0, 3:0, 3:1 and 2:3, respectively. Molecular analysis of mitochondrial genomes identified the known ND4 G11778A mutation and distinct sets of variants belonging to the Asian haplogroups M9a. Of these, the ND1 T3394C mutation caused the substitution of a highly conserved histidine for tyrosine (Y30H) at amino acid position 30. This mutation was associated with LHON in other families with low penetrance of optic neuropathy and other clinical abnormalities. The presence of both G11778A and T3394C mutations appears to contribute to higher penetrance of optic neuropathy in these four Chinese families than other Chinese families carrying only the G11778A mutation. Therefore, the mitochondrial haplogroup M9a specific variant T3394C may modulate the phenotypic manifestation of LHON-associated G11778A mutation in these Chinese pedigrees.
Collapse
Affiliation(s)
- Minglian Zhang
- Department of Ophthalmology, Xingtai Eye Hospital, Xingtai, Hebei, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Zhang J, Zhou X, Zhou J, Li C, Zhao F, Wang Y, Meng Y, Wang J, Yuan M, Cai W, Tong Y, Sun YH, Yang L, Qu J, Guan MX. Mitochondrial ND6 T14502C variant may modulate the phenotypic expression of LHON-associated G11778A mutation in four Chinese families. Biochem Biophys Res Commun 2010; 399:647-53. [PMID: 20691156 DOI: 10.1016/j.bbrc.2010.07.135] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 07/30/2010] [Indexed: 10/19/2022]
Abstract
We report here the clinical, genetic, and molecular evaluations of four Han Chinese families with Leber's hereditary optic neuropathy. Thirty-one (20 males/11 females) of 83 matrilineal relatives in these families exhibited the variable severity and age-at-onset in visual impairment. The average age-of-onset of vision loss was 22years old. Strikingly, these penetrances of visual impairment in these Chinese families were higher than those in other 11 Chinese pedigrees carrying the only ND4 G11778A mutation. Molecular analysis identified the known G11778A mutation and distinct sets of variants belonging to the Asian haplogroups M10a and M7c2. Of these, the T14502C mutation caused the substitution of a highly conserved isoleucine for valine at position 58 in ND6. This mutation has been associated with LHON in other Chinese families with very low penetrance of LHON. Thus, the deficient activities of complex I, caused by G11778A mutation, would be worsened by the T14502C mutation in these four Chinese families. As a result, mitochondrial dysfunctions would lead to the high penetrance and expressivity of visual loss in these Chinese families carrying both G11778A and T14502C mutations than other 11 Chinese families carrying only G11778A mutation. These data suggested that the T14502C variant may modulate the phenotypic manifestation of the G11778A mutation in these Chinese pedigrees.
Collapse
Affiliation(s)
- Juanjuan Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Zhou X, Zhang H, Zhao F, Ji Y, Tong Y, Zhang J, Zhang Y, Yang L, Qian Y, Lu F, Qu J, Guan MX. Very high penetrance and occurrence of Leber's hereditary optic neuropathy in a large Han Chinese pedigree carrying the ND4 G11778A mutation. Mol Genet Metab 2010; 100:379-84. [PMID: 20627642 PMCID: PMC2906641 DOI: 10.1016/j.ymgme.2010.04.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 04/22/2010] [Accepted: 04/22/2010] [Indexed: 02/06/2023]
Abstract
We report here the clinical, genetics and molecular characterization of a five-generation Han Chinese family with Leber's hereditary optic neuropathy (LHON). Strikingly, this family exhibits very high penetrance and occurrence of optic neuropathy. In particular, 25 (10 males/15 females) of 30 matrilineal relatives exhibited the variable severity, ranging from profound to mild of visual impairment. This penetrance of optic neuropathy in this Chinese family is much higher than those in many families with LHON worldwide. The age-at-onset for visual impairment in matrilineal relatives in this Chinese family varied from 7 to 24years old, with the average of 15 years old. Furthermore, the ratio between affected male and female matrilineal relatives is 1:1.5 in the Chinese family. This observation is in contrast with the typical features in LHON pedigrees that there was predominance of affected males in LHON in many families from different ethnic origins. Molecular analysis of mitochondrial genome identified the known ND4 G11778A mutation and 51 variants, belonging to Asian haplogroup C4a1. The absence of other known secondary LHON-associated and functionally significant mtDNA mutations in this Chinese family suggested that mitochondrial variants may not play an important role in the phenotypic manifestation of the G11778A mutation in this Chinese family. Therefore, nuclear modifier gene(s) may be responsible for very high penetrance and occurrence of optic neuropathy in this Chinese pedigree.
Collapse
Affiliation(s)
- Xiangtian Zhou
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Giuseppe Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Hongxing Zhang
- Department of Ophthalmology, Jinan Second People’s Hospital, Jinan, Shandong, China
| | - Fuxin Zhao
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Giuseppe Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Yanchun Ji
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Giuseppe Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Yi Tong
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
- The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian, China
| | - Juanjuan Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Giuseppe Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Yu Zhang
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Giuseppe Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Li Yang
- Divisions of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Yaping Qian
- Divisions of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Fan Lu
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Jia Qu
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Giuseppe Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Min-Xin Guan
- Giuseppe Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Divisions of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Corresponding authors: Min-Xin Guan, Ph.D., Division of Human Genetics, Cincinnati Children’s Hospital Medical, Center, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA; Telephone: (513) 636-3337; Fax: (513) 636-3486;
| |
Collapse
|
34
|
Qu J, Wang Y, Tong Y, Zhou X, Zhao F, Yang L, Zhang S, Zhang J, West CE, Guan MX. Leber's hereditary optic neuropathy affects only female matrilineal relatives in two Chinese families. Invest Ophthalmol Vis Sci 2010; 51:4906-12. [PMID: 20435583 DOI: 10.1167/iovs.09-5027] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
PURPOSE The purpose of this study was to investigate the role of modifier factors in the expression of Leber's hereditary optic neuropathy (LHON). METHODS Thirty-five subjects from two Han Chinese families with maternally transmitted LHON underwent a clinical and genetic evaluation and molecular analysis of mitochondrial (mt)DNA. RESULTS Matrilineal relatives in the two Chinese families exhibited a wide range of severity in visual impairment, from blindness to nearly normal vision. Very strikingly, all nine affected individuals of 21 matrilineal relatives (13 females/8 males) were female, which translates to 33% and 57% of penetrance for optic neuropathy in the two families. The average age at onset was 22 and 25 years. These observations were in contrast with typical features in many LHON pedigrees that have a predominance of affected males. Molecular analysis of their mtDNAs identified the homoplasmic ND4 G11778A mutation and distinct sets of variants belonging to the Asian haplogroups M1 and M10a. Of other variants, the L175F variant in CO3; the I58V variant in ND6; and the I189V, L292R, and S297A variants in CYTB were located at highly conserved residues of polypeptides. CONCLUSIONS Only female matrilineal relatives with a wide range of penetrance, severity, and age at onset of optic neuropathy in these two Chinese pedigrees showed the involvement of X-linked or autosomal recessive modifier genes in the phenotypic manifestation of the G11778A mutation. Furthermore, mitochondrial haplogroup-specific variants, together with epigenetic and environmental factors, may contribute to the phenotypic manifestation of the primary LHON-associated G11778A mutation in these pedigrees.
Collapse
Affiliation(s)
- Jia Qu
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Zhang YM, Ji YC, Liu XL, Zhou XT, Zhao FX, Sun YH, Wei QP, Zhang JJ, Liu Y, Qu J, Guan MX. [Leber's hereditary optic neuropathy may be associated with the mitochondrial tRNAGlu A14693G mutation in three Chinese families]. YI CHUAN = HEREDITAS 2010; 32:353-9. [PMID: 20423889 DOI: 10.3724/sp.j.1005.2010.00353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We reported here the clinical, genetic and molecular characterization of three Han Chinese families with Leber's hereditary optic neuropathy. Ophthalmologic examinations revealed the variable severity and age-at-onset of visual loss among probands and other matrilineal relatives of these families. Strikingly, these families exhibited extremely low penetrances of visual impairment. Sequence analysis of complete mitochondrial genomes in these pedigrees identified the known homoplasmic tRNAGlu A14693G mutation and distinct sets of polymorphism belonging to haplogroups Y1b, Y1 and Y1, respectively. The A14693G mutation occurs at the extremely conserved nucleotide (conventional position 54) of tRNAGlu. Thus, this mutation may alter structural formation and stabilization of functional tRNAs, thereby leading to a failure in tRNA metabolism and mitochondrial dysfunction involved in visual impairment. However, none of other variants showed the evolutionary conservation and functional significance. These observations suggested that the tRNAGlu A14693G mutation may be involved in the pathogenesis of optic neuropathy in these families.
Collapse
Affiliation(s)
- Yong-Mei Zhang
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou 325035, China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Tong Y, Sun YH, Zhou X, Zhao F, Mao Y, Wei QP, Yang L, Qu J, Guan MX. Very low penetrance of Leber's hereditary optic neuropathy in five Han Chinese families carrying the ND1 G3460A mutation. Mol Genet Metab 2010; 99:417-24. [PMID: 20053576 PMCID: PMC2839065 DOI: 10.1016/j.ymgme.2009.12.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Revised: 12/03/2009] [Accepted: 12/04/2009] [Indexed: 11/26/2022]
Abstract
We report here the clinical, genetic, and molecular characterization of five Han Chinese families with Leber's hereditary optic neuropathy (LHON). Strikingly, there were very low penetrances of visual impairment in these Chinese families, ranging from 4.2% to 22.2%, with an average of 10.2%. In particular, only 7 (4 males/3 females) of 106 matrilineal relatives in these families exhibited the variable severity and age-at-onset in visual dysfunction. The age-at-onset for visual impairment in matrilineal relatives in these families, varied from 20 to 25 years, with an average of 21.8 years old. Molecular analysis of mitochondrial genomes identified the homoplasmic ND1 G3460A mutation and distinct sets of variants, belonging to the Asian haplogroups B5b, C4a1, D5, F1, and R9, respectively. This suggests that the G3640A mutation occurred sporadically and multiplied through evolution of the mtDNA in China. However, there was the absence of known secondary LHON-associated mtDNA mutations in these Chinese families. Very low penetrance of visual loss in these five Chinese pedigrees strongly indicated that the G3640A mutation was itself insufficient to develop the optic neuropathy. The absence of secondary LHON mtDNA mutations suggest that these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the G3640A mutation in those Chinese families with low penetrance of vision loss. However, nuclear modifier genes, epigenetic and environmental factors appear to be modifier factors for the phenotypic manifestation of the G3640A mutation in these Chinese families.
Collapse
Affiliation(s)
- Yi Tong
- School of Ophthalmology and Optometry, and Eye Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
- Giuseppe Attardi Institute of Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
- The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian 350005, China
| | - Yan-Hong Sun
- Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine and Pharmacology, Beijing 100078, China
| | - Xiangtian Zhou
- School of Ophthalmology and Optometry, and Eye Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
| | - Fuxin Zhao
- School of Ophthalmology and Optometry, and Eye Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
| | - Yijian Mao
- School of Ophthalmology and Optometry, and Eye Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
| | - Qi-ping Wei
- Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine and Pharmacology, Beijing 100078, China
| | - Li Yang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Jia Qu
- School of Ophthalmology and Optometry, and Eye Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
- Giuseppe Attardi Institute of Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
- Corresponding authors. Addresses: Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA. Fax: +1 513 636 3486 (M.-X. Guan), School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China (J. Qu). (J. Qu), , (M.-X. Guan)
| | - Min-Xin Guan
- Giuseppe Attardi Institute of Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
- Corresponding authors. Addresses: Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA. Fax: +1 513 636 3486 (M.-X. Guan), School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China (J. Qu). (J. Qu), , (M.-X. Guan)
| |
Collapse
|
37
|
Seligmann H. The ambush hypothesis at the whole-organism level: Off frame, ‘hidden’ stops in vertebrate mitochondrial genes increase developmental stability. Comput Biol Chem 2010; 34:80-5. [DOI: 10.1016/j.compbiolchem.2010.03.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Accepted: 03/02/2010] [Indexed: 01/24/2023]
|
38
|
Blood pressure treatment in acute ischemic stroke: a review of studies and recommendations. Curr Opin Neurol 2010; 23:46-52. [PMID: 20038827 DOI: 10.1097/wco.0b013e3283355694] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE OF REVIEW Elevated blood pressure (BP) is frequent in patients with acute ischemic stroke. Pathophysiological data support its usefulness to maintain adequate perfusion of the ischemic penumba. This review article aims to summarize the available evidence from clinical studies that examined the prognostic role of BP during the acute phase of ischemic stroke and intervention studies that assessed the efficacy of active BP alteration. RECENT FINDINGS We found 34 observational studies (33,470 patients), with results being inconsistent among the studies; most studies reported a negative association between increased levels of BP and clinical outcome, whereas a few studies showed clinical improvement with higher BP levels, clinical deterioration with decreased BP, or no association at all. Similarly, the conclusions drawn by the 18 intervention studies included in this review (1637 patients) were also heterogeneous. Very recent clinical data suggest a possible beneficial effect of early treatment with some antihypertensives on late clinical outcome. SUMMARY Observational and interventional studies of management of acute poststroke hypertension yield conflicting results. We discuss different explanations that may account for this and discuss the current guidelines and pathophysiological considerations for the management of acute poststroke hypertension.
Collapse
|
39
|
Liu Y, Zhuang SL, Tong Y, Qu J, Zhou XT, Zhao FX, Zhang JJ, Zhang YM, Zhang Y, Guan MX. [Leber's hereditary optic neuropathy and limbs abnormity claudication may be associated with the mitochondrial ND1 T3866C mutation]. YI CHUAN = HEREDITAS 2010; 32:141-7. [PMID: 20176558 DOI: 10.3724/sp.j.1005.2010.00141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Mutations in mitochondrial DNA have been associated with a wide spectrum of clinical abnormalities. We reported here the clinical, genetic and molecular characterization of a five-generation Han Chinese pedigree with Leber's Hereditary Optic Neuropathy (LHON) and limbs abnormity claudication. Of 27 matrilineal relatives, four exhibited only LHON, one suffered from only limbs abnormity claudication, and four had both LHON and limbs abnormity claudication. Sequence analysis of mitochondrial genome in this family identified the known T3866C mutation in ND1 gene and other 43 variants belonging to the Asian haplogroup D4a3. The T3866C (I187T) mutation resulted in the replacement of isoleucine at position 187 with theronine. The isoleucine at position 187 located at one of transmembrane domain in ND1 polypeptide. The isoleucine at position 187 was extremely conserved among 29 organisms, while other variants showed no evolutionarily conservation. Furthermore, the T3866C was absence in 135 Chinese control subjects. The T3866C mutation likely alters the complex I activity, which causes mitochondrial dysfunction associated with LHON and limbs abnormity claudication. Therefore, the T3866C mutation is likely associated with LHON and limbs abnormity claudication.
Collapse
Affiliation(s)
- Yan Liu
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou 325035, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Qu J, Zhou X, Zhao F, Liu X, Zhang M, Sun YH, Liang M, Yuan M, Liu Q, Tong Y, Wei QP, Yang L, Guan MX. Low penetrance of Leber's hereditary optic neuropathy in ten Han Chinese families carrying the ND6 T11484C mutation. Biochim Biophys Acta Gen Subj 2009; 1800:305-12. [PMID: 19733221 DOI: 10.1016/j.bbagen.2009.08.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Revised: 08/22/2009] [Accepted: 08/26/2009] [Indexed: 11/27/2022]
Abstract
BACKGROUND Leber's hereditary optic neuropathy (LHON) is a maternally inherited disorder. The purpose of this investigation is to understand the role of mitochondrial haplotypes in the development of LHON associated with ND6 T14484C mutation in Chinese families. METHODS One hundred fourteen subjects from ten Han Chinese families with LHON were studied by the clinical and genetic evaluation as well as molecular and biochemical analyses of mitochondrial DNA (mtDNA). RESULTS Clinical evaluation revealed that ten families exhibited extremely low penetrance of visual impairment, with an average of 10%. In particular, ten (8 males/2 females) of 114 matrilineal relatives in these families exhibited the variable severity and age-at-onset in visual dysfunction. The average age-of-onset of vision loss was 19 years old. Molecular analysis of mitochondrial DNA (mtDNA) identified the homoplasmic T14484C mutation and distinct sets of variants, belonging to the Asian haplogroups B5b, D4, D4g1b, G3a2, R11, R11a and Z3, respectively. However, there was the absence of secondary LHON-associated mtDNA mutations in these ten Chinese families. CONCLUSION The low penetrance of vision loss in these Chinese pedigrees strongly indicated that the T14484C mutation was itself insufficient to produce a clinical phenotype. The absence of secondary LHON mtDNA mutations suggests that these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the T14484C mutation in those Chinese families with low penentrace of vision loss. However, nuclear modifier genes and environmental factors appear to be modifier factors for the phenotypic manifestation of the T14484C mutation in these Chinese families.
Collapse
Affiliation(s)
- Jia Qu
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003, China.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Zhao F, Guan M, Zhou X, Yuan M, Liang M, Liu Q, Liu Y, Zhang Y, Yang L, Tong Y, Wei QP, Sun YH, Qu J, Guan MX. Leber's hereditary optic neuropathy is associated with mitochondrial ND6 T14502C mutation. Biochem Biophys Res Commun 2009; 389:466-72. [PMID: 19732751 DOI: 10.1016/j.bbrc.2009.08.168] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Accepted: 08/31/2009] [Indexed: 11/17/2022]
Abstract
We report here the clinical, genetic, and molecular characterization of three Chinese families with Leber's hereditary optic neuropathy (LHON). There were variable severity and age of onset in visual impairment among these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of complete mitochondrial genomes in these pedigrees showed the homoplasmic T14502C (I58V) mutation, which localized at a highly conserved isoleucine at position 58 of ND6, and distinct sets of mtDNA polymorphisms belonging to haplogroups M10a, F1a1, and H2. The occurrence of T14502C mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. Here, mtDNA variants I187T in the ND1, A122V in CO1, S99A in the A6, and V254I in CO3 exhibited an evolutionary conservation, indicating a potential modifying role in the development of visual impairment associated with T14502C mutation in those families. Furthermore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic manifestation of the LHON-associated T14502C mutation in these Chinese families.
Collapse
Affiliation(s)
- Fuxin Zhao
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Li R, Liu Y, Li Z, Yang L, Wang S, Guan MX. Failures in mitochondrial tRNAMet and tRNAGln metabolism caused by the novel 4401A>G mutation are involved in essential hypertension in a Han Chinese Family. Hypertension 2009; 54:329-37. [PMID: 19546379 DOI: 10.1161/hypertensionaha.109.129270] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We report here on the clinical, genetic, and molecular characterization of 1 Han Chinese family with maternally transmitted hypertension. Three of 7 matrilineal relatives in this 4-generation family exhibited the variable degree of essential hypertension at the age at onset, ranging from 35 to 60 years old. Sequence analysis of the complete mitochondrial DNA in this pedigree identified the novel homoplasmic 4401A>G mutation localizing at the spacer immediately to the 5' end of tRNA(Met) and tRNA(Gln) genes and 39 other variants belonging to the Asian haplogroup C. The 4401A>G mutation was absent in 242 Han Chinese controls. Approximately 30% reductions in the steady-state levels of tRNA(Met) and tRNA(Gln) were observed in 2 lymphoblastoid cell lines carrying the 4401A>G mutation compared with 2 control cell lines lacking this mutation. Failures in mitochondrial metabolism are apparently a primary contributor to the reduced rate of mitochondrial translation and reductions in the rate of overall respiratory capacity, malate/glutamate-promoted respiration, succinate/glycerol-3-phosphate-promoted respiration, or N,N,N',N'-tetramethyl-p-phenylenediamine/ascorbate-promoted respiration in lymphoblastoid cell lines carrying the 4401A>G mutation. The homoplasmic form, mild biochemical defect, late onset, and incomplete penetrance of hypertension in this family suggest that the 4401A>G mutation itself is insufficient to produce a clinical phenotype. Thus, the other modifier factors, eg, nuclear modifier genes and environmental and personal factors, may also contribute to the development of hypertension in these subjects carrying this mutation. These data suggest that mitochondrial dysfunctions, caused by the 4401A>G mutation, are involved in the development of hypertension in this Chinese pedigree.
Collapse
Affiliation(s)
- Ronghua Li
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
| | | | | | | | | | | |
Collapse
|
43
|
Liu Y, Li R, Li Z, Wang XJ, Yang L, Wang S, Guan MX. Mitochondrial transfer RNAMet 4435A>G mutation is associated with maternally inherited hypertension in a Chinese pedigree. Hypertension 2009; 53:1083-90. [PMID: 19398658 PMCID: PMC2907152 DOI: 10.1161/hypertensionaha.109.128702] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Mitochondrial DNA mutations have been associated with cardiovascular disease. We report here the clinical, genetic, and molecular characterization of 1 Han Chinese family with suggestively maternally transmitted hypertension. Matrilineal relatives in this family exhibited the variable degree of hypertension at the age at onset of 44 to 55 years old. Sequence analysis of entire mitochondrial DNA in this pedigree identified the known homoplasmic 4435A>G mutation, which is located immediately at the 3 prime end to the anticodon, corresponding with the conventional position 37 of tRNA(Met), and 35 other variants belonging to the Asian haplogroup B5a. The adenine (A37) at this position of tRNA(Met) is extraordinarily conserved from bacteria to human mitochondria. This modified A37 was shown to contribute to the high fidelity of codon recognition, the structural formation, and stabilization of functional tRNAs. In fact, a 40% reduction in the levels of tRNA(Met) was observed in cells carrying the 4435A>G mutation. As a result, a failure in mitochondrial tRNA metabolism, caused by the 4435A>G mutation, led to approximately 30% reduction in the rate of mitochondrial translation. However, the homoplasmic form, mild biochemical defect, and late onset of hypertension in subjects carrying the 4435A>G mutation suggest that the 4435A>G mutation itself is insufficient to produce a clinical phenotype. The other modifier factors, such as nuclear modifier genes, environmental, and personal factors may also contribute to the development of hypertension in the subjects carrying this mutation. Our findings imply that the 4435A>G mutation may act as an inherited risk factor for the development of hypertension in this Chinese pedigree.
Collapse
Affiliation(s)
- Yuqi Liu
- Institute of Geriatric Cardiology, Chinese People's Liberation Army General Hospital, Beijing, China
| | | | | | | | | | | | | |
Collapse
|
44
|
Liang M, Guan M, Zhao F, Zhou X, Yuan M, Tong Y, Yang L, Wei QP, Sun YH, Lu F, Qu J, Guan MX. Leber's hereditary optic neuropathy is associated with mitochondrial ND1 T3394C mutation. Biochem Biophys Res Commun 2009; 383:286-92. [PMID: 19324017 DOI: 10.1016/j.bbrc.2009.03.097] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2009] [Accepted: 03/18/2009] [Indexed: 12/22/2022]
Abstract
We report here the clinical, genetic and molecular characterization of four Chinese families with Leber's hereditary optic neuropathy (LHON). There were variable severity and age-of-onset in visual impairment among these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of complete mitochondrial genomes in these pedigrees showed the homoplasmic T3394C (Y30H) mutation, which localized at a highly conserved tyrosine at position 30 of ND1, and distinct sets of mtDNA polymorphisms belonging to haplogroups D4b and M9a. The occurrence of T3394C mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. However, there was the absence of functionally significant mtDNA mutations in these four Chinese pedigrees carrying the T3394C mutation. Therefore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic expression of the LHON-associated T3394C mutation.
Collapse
Affiliation(s)
- Min Liang
- Wenzhou Medical College, Zhejiang, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|