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Zou W, Zong K, Zhang Z, Shen L, Wang X, Su X, Wang X, Yin T, Liang C, Liu Y, Liang D, Hu C, Cao Y, Ji D. Novel economical, accurate, sensitive, single-cell analytical method for mitochondrial DNA quantification in mtDNA mutation carriers. J Assist Reprod Genet 2023; 40:2197-2209. [PMID: 37462790 PMCID: PMC10440311 DOI: 10.1007/s10815-023-02878-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 06/20/2023] [Indexed: 08/22/2023] Open
Abstract
PURPOSE Although a variety of analytical methods have been developed to detect mitochondrial DNA (mtDNA) heteroplasmy, there are special requirements of mtDNA heteroplasmy quantification for women carrying mtDNA mutations receiving the preimplantation genetic diagnosis (PGD) and prenatal diagnosis (PD) in clinic. These special requirements include various sample types, large sample number, long-term follow-up, and the need for detection of single-cell from biopsied embryos. Therefore, developing an economical, accurate, high-sensitive, and single-cell analytical method for mtDNA heteroplasmy is necessary. METHODS In this study, we developed the Sanger sequencing combined droplet digital polymerase chain reaction (ddPCR) method for mtDNA quantification and compared the results to next-generation sequencing (NGS). A total of seventeen families with twelve mtDNA mutations were recruited in this study. RESULTS The results showed that both Sanger sequencing and ddPCR could be used to analyze the mtDNA heteroplasmy in single-cell samples. There was no statistically significant difference in heteroplasmy levels in common samples with high heteroplasmy (≥ 5%), low heteroplasmy (< 5%), and single-cell samples, either between Sanger sequencing and NGS methods, or between ddPCR and NGS methods (P > 0.05). However, Sanger sequencing was unable to detect extremely low heteroplasmy accurately. But even in samples with extremely low heteroplasmy (0.40% and 0.92%), ddPCR was always able to quantify them. Compared to NGS, Sanger sequencing combined ddPCR analytical methods greatly reduced the cost of sequencing. CONCLUSIONS In conclusion, this study successfully established an economical, accurate, sensitive, single-cell analytical method based on the Sanger sequencing combined ddPCR methods for mtDNA heteroplasmy quantification in a clinical setting.
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Affiliation(s)
- Weiwei Zou
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Kai Zong
- Technical Center of Hefei Customs District, No. 329 Tunxi Road, Hefei, 230022, Anhui, China
| | - Zhikang Zhang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Lingchao Shen
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Xiaolei Wang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Xun Su
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Xin Wang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Tao Yin
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Chunmei Liang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Yajing Liu
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Dan Liang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Chao Hu
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Yunxia Cao
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China.
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China.
| | - Dongmei Ji
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China.
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China.
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Finsterer J, Ghosh R. Effective treatment of choreaballism due to an MT-CYB variant with haloperidol, tetrabenazine, and antioxidants. Clin Case Rep 2023; 11:e7592. [PMID: 37351357 PMCID: PMC10282112 DOI: 10.1002/ccr3.7592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/03/2023] [Accepted: 06/07/2023] [Indexed: 06/24/2023] Open
Abstract
Hypokinetic and hyperkinetic movement disorders are a common phenotypic feature of mitochondrial disorders. Choreaballism has been reported particularly in patients with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes syndrome and in maternally inherited diabetes and deafness syndrome. The pathophysiological basis of movement disorders in mitochondrial disorders is the involvement of the basal ganglia or the midbrain. Haloperidol and mitochondrial cocktails have proven beneficial in some of these cases. Here we present another patient with mitochondrial choreaballism who benefited significantly from symptomatic therapy. The patient is a 14-year-old male with a history of hypoacusis, ptosis, and focal tonic-clonic seizures of the upper/lower limbs on either side since childhood. Since this time he has also developed occasional, abnormal involuntary limb movements, choreaballism, facial grimacing, carpopedal spasms, and abnormal lip sensations. He was diagnosed with a non-syndromic mitochondrial disorder after detection of the variant m.15043G > A in MT-CYB. Seizures have been successfully treated with lamotrigine. Hypocalcemia was treated with intravenous calcium. For hypoparathyroidism calcitriol was given. Choreaballism was treated with haloperidol and tetrabenazine. In addition, he received coenzyme Q10, L-carnitine, thiamine, riboflavin, alpha-lipoic acid, biotin, vitamin-C, vitamin-E, and creatine-monohydrate. With this therapy, the choreaballism disappeared completely. This case shows that mitochondrial disorders can manifest with cognitive impairment, seizures, movement disorder, hypoacusis, endocrinopathy, cardiomyopathy, neuropathy, and myopathy, that choreaballism can be a phenotypic feature of multisystem mitochondrial disorders, and that choreaballism favorably responds to haloperidol, tetrabenazine, and possibly to a cocktail of antioxidants, cofactors, and vitamins.
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Affiliation(s)
| | - Ritwik Ghosh
- Department of General MedicineBurdwan Medical College & HospitalBurdwanWest BengalIndia
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Ding X, Fang T, Pang X, Pan X, Tong A, Lin Z, Zheng S, Zheng N. Mitochondrial DNA abnormalities and metabolic syndrome. Front Cell Dev Biol 2023; 11:1153174. [PMID: 36968196 PMCID: PMC10036395 DOI: 10.3389/fcell.2023.1153174] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 02/27/2023] [Indexed: 03/12/2023] Open
Abstract
Metabolic syndrome (MetS) is a complex pathological condition that involves disrupted carbohydrate, protein, and fat metabolism in the human body, and is a major risk factor for several chronic diseases, including diabetes, cardiovascular disease, and cerebrovascular disease. While the exact pathogenesis of metabolic syndrome is not yet fully understood, there is increasing evidence linking mitochondrial dysfunction, which is closely related to the mitochondrial genome and mitochondrial dynamics, to the development of this condition. Recent advancements in genetic sequencing technologies have allowed for more accurate detection of mtDNA mutations and other mitochondrial abnormalities, leading to earlier diagnosis and intervention in patients with metabolic syndrome. Additionally, the identification of specific mechanisms by which reduced mtDNA copy number and gene mutations, as well as abnormalities in mtDNA-encoded proteins and mitochondrial dynamics, contribute to metabolic syndrome may promote the development of novel therapeutic targets and interventions, such as the restoration of mitochondrial function through the targeting of specific mitochondrial defects. Additionally, advancements in genetic sequencing technologies may allow for more accurate detection of mtDNA mutations and other mitochondrial abnormalities, leading to earlier diagnosis and intervention in patients with MetS. Therefore, strategies to promote the restoration of mitochondrial function by addressing these defects may offer new options for treating MetS. This review provides an overview of the research progress and significance of mitochondrial genome and mitochondrial dynamics in MetS.
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Affiliation(s)
- Xudong Ding
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Liaoning, China
| | - Tingting Fang
- Department of Pathophysiology, College of Basic Medical Science, China Medical University, Liaoning, China
| | - Xiaoqi Pang
- Shengjing Hospital, China Medical University, Liaoning, China
| | - Xueru Pan
- Pharmaceutical Sciences, China Medical University-The Queen’s University of Belfast Joint College, China Medical University, Liaoning, China
| | - Aiying Tong
- Pharmaceutical Sciences, China Medical University-The Queen’s University of Belfast Joint College, China Medical University, Liaoning, China
| | - Ziyi Lin
- Pharmaceutical Sciences, China Medical University-The Queen’s University of Belfast Joint College, China Medical University, Liaoning, China
| | - Shikuan Zheng
- Pharmaceutical Sciences, China Medical University-The Queen’s University of Belfast Joint College, China Medical University, Liaoning, China
| | - Ningning Zheng
- Department of Pathophysiology, College of Basic Medical Science, China Medical University, Liaoning, China
- *Correspondence: Ningning Zheng,
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Baide-Mairena H, Marti-Sánchez L, Marcé-Grau A, Cazurro-Gutiérrez A, Sanchez-Montanez A, Delgado I, Moreno-Galdó A, Macaya-Ruiz A, García-Arumí E, Pérez-Dueñas B. Genetic diagnosis of basal ganglia disease in childhood. Dev Med Child Neurol 2022; 64:743-752. [PMID: 34988976 DOI: 10.1111/dmcn.15125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 11/07/2021] [Accepted: 11/08/2021] [Indexed: 11/29/2022]
Abstract
AIM To correlate clinical, radiological, and biochemical features with genetic findings in children with bilateral basal ganglia lesions of unknown aetiology, and propose a diagnostic algorithm for early recognition. METHOD Children with basal ganglia disease were recruited in a 2-year prospective multicentre study for clinical, biomarker, and genetic studies. Radiological pattern recognition was examined by hierarchical clustering analysis. RESULTS We identified 22 genetic conditions in 30 out of 62 paediatric patients (37 males, 25 females; mean age at onset 2y, SD 3; range 0-10y; mean age at assessment 11y, range 1-25y) through gene panels (n=11), whole-exome sequencing (n=13), and mitochondrial DNA (mtDNA) sequencing (n=6). Genetic aetiologies included mitochondrial diseases (57%), Aicardi-Goutières syndrome (20%), and monogenic causes of dystonia and/or epilepsy (17%) mimicking Leigh syndrome. Radiological abnormalities included T2-hyperintense lesions (n=26) and lesions caused by calcium or manganese mineralization (n=9). Three clusters were identified: the pallidal, neostriatal, and striatal, plus the last including mtDNA defects in the oxidative phosphorylation system with prominent brain atrophy. Mitochondrial biomarkers showed poor sensitivity and specificity in children with mitochondrial disease, whereas interferon signature was observed in all patients with patients with Aicardi-Goutières syndrome. INTERPRETATION Combined whole-exome and mtDNA sequencing allowed the identification of several genetic conditions affecting basal ganglia metabolism. We propose a diagnostic algorithm which prioritizes early use of next-generation sequencing on the basis of three clusters of basal ganglia lesions.
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Affiliation(s)
- Heidy Baide-Mairena
- Paediatric Neurology Research Group, Vall d´Hebron Research Institut, Universitat Autònoma de Barcelona, Barcelona, Spain.,Department of Pediatrics, Granollers General Hospital, Granollers, Spain
| | - Laura Marti-Sánchez
- Department of Biochemistry, Sant Joan de Déu Research Institut, Universitat de Barcelona, Barcelona, Spain
| | - Anna Marcé-Grau
- Paediatric Neurology Research Group, Vall d´Hebron Research Institut, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Ana Cazurro-Gutiérrez
- Paediatric Neurology Research Group, Vall d´Hebron Research Institut, Universitat Autònoma de Barcelona, Barcelona, Spain
| | | | - Ignacio Delgado
- Department of Neuroradiology, Vall d'Hebron University Hospital, Barcelona, Spain
| | - Antonio Moreno-Galdó
- Vall d'Hebron Research Institut (VHIR), Vall d'Hebron Barcelona Hospital Campus, Barcelona, Spain.,Department of Pediatrics, Vall d'Hebron Barcelona Hospital Campus Barcelona, Universitat Autònoma de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain
| | - Alfons Macaya-Ruiz
- Paediatric Neurology Research Group, Vall d´Hebron Research Institut, Universitat Autònoma de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain.,Department of Paediatric Neurology, Vall d`Hebron University Hospital, Barcelona, Spain
| | - Elena García-Arumí
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain.,Research Group on Neuromuscular and Mitochondrial Disorders, Vall d'Hebron Research Institut (VHIR), Barcelona, Spain.,Department of Clinical and Molecular Genetics, Vall d'Hebron University Hospital, Barcelona, Spain
| | - Belén Pérez-Dueñas
- Paediatric Neurology Research Group, Vall d´Hebron Research Institut, Universitat Autònoma de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain.,Department of Paediatric Neurology, Vall d`Hebron University Hospital, Barcelona, Spain
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Bi H, Guo H, Wang Q, Zhang X, Zhao Y, Li J, Zhao W, Tuo H, Zhang Y. A Novel Variation in the Mitochondrial Complex I Assembly Factor NDUFAF5 Causes Isolated Bilateral Striatal Necrosis in Childhood. Front Neurol 2021; 12:675616. [PMID: 34177781 PMCID: PMC8223072 DOI: 10.3389/fneur.2021.675616] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/13/2021] [Indexed: 01/30/2023] Open
Abstract
Background: Bilateral striatal necrosis (BSN) is characterized by symmetrical degeneration, predominantly of the caudate and putamen nucleus, in the basal ganglia. It is associated with numerous acquired and hereditary neuro-developmental and motor dysfunction-related pathological conditions. BSN results in high morbidity and mortality among infants and children, and its diagnosis is clinically challenging due to several overlapping disease phenotypes. Therefore, a precise genetic diagnosis is urgently needed for accurate genetic counseling and improved prognostic outcomes as well. Objective: To identify novel missense mutations in the NDUFAF5 gene as a cause of childhood BSN in members of a Chinese family and summarize the clinical characteristics of patients with the NDUFAF5 gene mutations. Methods: This study included a large family living in a remote northwestern area of China. Three siblings developed a neurological disorder characterized by generalized dystonia within the first decade of their lives. Cerebral computed tomography (CT) and magnetic resonance imaging (MRI) showed bilateral lesions of the putamen. Biochemical and genetic approaches were used to identify the cause of BSN. Results: Sequence analysis showed no pathogenic variation in PANK2, SLC25A19, SLC19A3, and NUP62 genes and in the entire mitochondrial genome as well. Whole-exome sequencing revealed compound heterozygous mutations consisting of NDUFAF5:c.425A > C(p.E142A) and c.836T > G (p.M279R). The father, a healthy sister, and a healthy brother of the affected siblings carried the c.836T > G mutation, and the mother carried the c.425A > C mutation. These variants were absent in 100 ethnically matched non-BSN controls. In silico analysis demonstrated that the E142A and M279R mutations in NDUFAF5 protein significantly perturbed the normal conformation of the protein due to alterations in the hydrogen bonding patterns around the evolutionarily conserved catalytic domains, leading to its loss of function in the early stage of mitochondrial complex I assembly. Conclusions: We identified a novel compound heterozygous mutation (c.425A > C and c.836T > G) in the NDUFAF5 gene as the potential cause of autosomal recessive childhood BSN, which extended the pathogenic variation spectrum of the NDUFAF5 gene. This study provides substantial evidence for further improvement of genetic counseling and better clinical management of BSN affected individuals.
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Affiliation(s)
- Hongyan Bi
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Hui Guo
- Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, China
| | - Qianfei Wang
- CAS Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Xiao Zhang
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Yaming Zhao
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Jimei Li
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Weiqin Zhao
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Houzhen Tuo
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Yongbo Zhang
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
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Neuropathology and pathogenesis of extrapyramidal movement disorders: a critical update. II. Hyperkinetic disorders. J Neural Transm (Vienna) 2019; 126:997-1027. [DOI: 10.1007/s00702-019-02030-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 06/14/2019] [Indexed: 12/14/2022]
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7
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Zhong S, Wen S, Qiu Y, Yu Y, Xin L, He Y, Gao X, Fang H, Hong D, Zhang J. Bilateral striatal necrosis due to homoplasmic mitochondrial 3697G>A mutation presents with incomplete penetrance and sex bias. Mol Genet Genomic Med 2019; 7:e541. [PMID: 30623604 PMCID: PMC6418351 DOI: 10.1002/mgg3.541] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/09/2018] [Accepted: 12/02/2018] [Indexed: 12/28/2022] Open
Abstract
Background Heteroplasmic mitochondrial 3697G>A mutation has been associated with leber hereditary optic neuropathy (LHON), mitochondrial encephalopathy, lactic acidosis and stroke‐like episodes (MELAS), and LHON/MELAS overlap syndrome. However, homoplasmic m.3697G>A mutation was only found in a family with Leigh syndrome, and the phenotype and pathogenicity of this homoplasmic mutation still need to be investigated in new patients. Methods The clinical interviews were conducted in 12 individuals from a multiple‐generation inherited family. Mutations were screened through exome next‐generation sequencing and subsequently confirmed by PCR‐restriction fragment length polymorphism. Mitochondrial complex activities and ATP production rate were measured by biochemical analysis. Results The male offspring with bilateral striatal necrosis (BSN) were characterized by severe spastic dystonia and complete penetrance, while the female offspring presented with mild symptom and low penetrance. All offspring carried homoplasmic mutation of NC_012920.1: m.3697G>A, p.(Gly131Ser). Biochemical analysis revealed an isolated defect of complex I, but the magnitude of the defect was higher in the male patients than that in the female ones. The ATP production rate also exhibited a similar pattern. However, no possible modifier genes on the X chromosome were identified. Conclusion Homoplasmic m.3697G>A mutation could be associated with BSN, which expanded the clinical spectrum of m.3697G>A. Our preliminary investigations had not found the underlying modifiers to support the double hit hypothesis, while the high level of estrogens in the female patients might exert a potential compensatory effect on mutant cell metabolism.
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Affiliation(s)
- Shanshan Zhong
- Department of Neurology, Peking University People's Hospital, Beijing, China
| | - Shumeng Wen
- Key Laboratory of Laboratory Medicine, College of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China
| | - Yusen Qiu
- Department of Neurology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yanyan Yu
- Department of Neurology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Ling Xin
- Department of Health, Exercise Science, and Recreation Management, University of Mississippi, University, Mississippi
| | - Yang He
- Department of Neurology, Peking University People's Hospital, Beijing, China
| | - Xuguang Gao
- Department of Neurology, Peking University People's Hospital, Beijing, China
| | - Hezhi Fang
- Key Laboratory of Laboratory Medicine, College of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China
| | - Daojun Hong
- Department of Neurology, Peking University People's Hospital, Beijing, China
| | - Jun Zhang
- Department of Neurology, Peking University People's Hospital, Beijing, China
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