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Deng X, Yuan L, Jankovic J, Deng H. The role of the PLA2G6 gene in neurodegenerative diseases. Ageing Res Rev 2023; 89:101957. [PMID: 37236368 DOI: 10.1016/j.arr.2023.101957] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 05/12/2023] [Accepted: 05/17/2023] [Indexed: 05/28/2023]
Abstract
PLA2G6-associated neurodegeneration (PLAN) represents a continuum of clinically and genetically heterogeneous neurodegenerative disorders with overlapping features. Usually, it encompasses three autosomal recessive diseases, including infantile neuroaxonal dystrophy or neurodegeneration with brain iron accumulation (NBIA) 2A, atypical neuronal dystrophy with childhood-onset or NBIA2B, and adult-onset dystonia-parkinsonism form named PARK14, and possibly a certain subtype of hereditary spastic paraplegia. PLAN is caused by variants in the phospholipase A2 group VI gene (PLA2G6), which encodes an enzyme involved in membrane homeostasis, signal transduction, mitochondrial dysfunction, and α-synuclein aggregation. In this review, we discuss PLA2G6 gene structure and protein, functional findings, genetic deficiency models, various PLAN disease phenotypes, and study strategies in the future. Our primary aim is to provide an overview of genotype-phenotype correlations of PLAN subtypes and speculate on the role of PLA2G6 in potential mechanisms underlying these conditions.
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Affiliation(s)
- Xinyue Deng
- Health Management Center, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China; Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China; Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China
| | - Lamei Yuan
- Health Management Center, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China; Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China; Disease Genome Research Center, Central South University, Changsha 410013, Hunan, China
| | - Joseph Jankovic
- Parkinson's Disease Center and Movement Disorders Clinic, Department of Neurology, Baylor College of Medicine, Houston, TX 77030-4202, USA
| | - Hao Deng
- Health Management Center, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China; Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China; Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China; Disease Genome Research Center, Central South University, Changsha 410013, Hunan, China.
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2
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Neurodegeneration with brain iron accumulation: a case series highlighting phenotypic and genotypic diversity in 20 Indian families. Neurogenetics 2023; 24:113-127. [PMID: 36790591 DOI: 10.1007/s10048-023-00712-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 01/25/2023] [Indexed: 02/16/2023]
Abstract
Neurodegeneration with brain iron accumulation (NBIA) is an umbrella term encompassing various inherited neurological disorders characterised by abnormal iron accumulation in basal ganglia. We aimed to study the clinical, radiological and molecular spectrum of disorders with NBIA. All molecular-proven cases of NBIA presented in the last 5 years at 2 tertiary care genetic centres were compiled. Demographic details and clinical and neuroimaging findings were collated. We describe 27 individuals from 20 unrelated Indian families with causative variants in 5 NBIA-associated genes. PLA2G6-associated neurodegeneration (PLAN) was the most common, observed in 13 individuals from 9 families. They mainly presented in infancy with neuroregression and hypotonia. A recurrent pathogenic variant in COASY was observed in two neonates with prenatal-onset severe neurodegeneration. Pathogenic bi-allelic variants in PANK2, FA2H and C19ORF12 genes were observed in the rest, and these individuals presented in late childhood and adolescence with gait abnormalities and extrapyramidal symptoms. No intrafamilial and interfamilial variability were observed. Iron deposition on neuroimaging was seen in only 6/17 (35.3%) patients. A total of 22 causative variants across 5 genes were detected including a multiexonic duplication in PLA2G6. The variants c.1799G > A and c.2370 T > G in PLA2G6 were observed in three unrelated families. In silico assessments of 8 amongst 9 novel variants were also performed. We present a comprehensive compilation of the phenotypic and genotypic spectrum of various subtypes of NBIA from the Indian subcontinent. Clinical presentation of NBIAs is varied and not restricted to extrapyramidal symptoms or iron accumulation on neuroimaging.
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Hinarejos I, Machuca C, Sancho P, Espinós C. Mitochondrial Dysfunction, Oxidative Stress and Neuroinflammation in Neurodegeneration with Brain Iron Accumulation (NBIA). Antioxidants (Basel) 2020; 9:antiox9101020. [PMID: 33092153 PMCID: PMC7589120 DOI: 10.3390/antiox9101020] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/16/2020] [Accepted: 10/17/2020] [Indexed: 12/13/2022] Open
Abstract
The syndromes of neurodegeneration with brain iron accumulation (NBIA) encompass a group of invalidating and progressive rare diseases that share the abnormal accumulation of iron in the basal ganglia. The onset of NBIA disorders ranges from infancy to adulthood. Main clinical signs are related to extrapyramidal features (dystonia, parkinsonism and choreoathetosis), and neuropsychiatric abnormalities. Ten NBIA forms are widely accepted to be caused by mutations in the genes PANK2, PLA2G6, WDR45, C19ORF12, FA2H, ATP13A2, COASY, FTL1, CP, and DCAF17. Nonetheless, many patients remain without a conclusive genetic diagnosis, which shows that there must be additional as yet undiscovered NBIA genes. In line with this, isolated cases of known monogenic disorders, and also, new genetic diseases, which present with abnormal brain iron phenotypes compatible with NBIA, have been described. Several pathways are involved in NBIA syndromes: iron and lipid metabolism, mitochondrial dynamics, and autophagy. However, many neurodegenerative conditions share features such as mitochondrial dysfunction and oxidative stress, given the bioenergetics requirements of neurons. This review aims to describe the existing link between the classical ten NBIA forms by examining their connection with mitochondrial impairment as well as oxidative stress and neuroinflammation.
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Affiliation(s)
- Isabel Hinarejos
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), 46012 Valencia, Spain; (I.H.); (C.M.); (P.S.)
- Rare Diseases Joint Units, CIPF-IIS La Fe & INCLIVA, 46012 Valencia, Spain
| | - Candela Machuca
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), 46012 Valencia, Spain; (I.H.); (C.M.); (P.S.)
- Rare Diseases Joint Units, CIPF-IIS La Fe & INCLIVA, 46012 Valencia, Spain
- Unit of Stem Cells Therapies in Neurodegenerative Diseases, Centro de Investigación Príncipe Felipe (CIPF), 46012 Valencia, Spain
| | - Paula Sancho
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), 46012 Valencia, Spain; (I.H.); (C.M.); (P.S.)
- Rare Diseases Joint Units, CIPF-IIS La Fe & INCLIVA, 46012 Valencia, Spain
| | - Carmen Espinós
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), 46012 Valencia, Spain; (I.H.); (C.M.); (P.S.)
- Rare Diseases Joint Units, CIPF-IIS La Fe & INCLIVA, 46012 Valencia, Spain
- Department of Genetics, University of Valencia, 46100 Valencia, Spain
- Correspondence: ; Tel.: +34-963-289-680
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4
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Balicza P, Bencsik R, Lengyel A, Gal A, Grosz Z, Csaban D, Rudas G, Danics K, Kovacs GG, Molnar MJ. Novel dominant MPAN family with a complex genetic architecture as a basis for phenotypic variability. Neurol Genet 2020; 6:e515. [PMID: 33134513 PMCID: PMC7577556 DOI: 10.1212/nxg.0000000000000515] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/27/2020] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Our aim was to study a Hungarian family with autosomal dominantly inherited neurodegeneration with brain iron accumulation (NBIA) with markedly different intrafamilial expressivity. METHODS Targeted sequencing and multiplex ligation-dependent probe amplification (MLPA) of known NBIA-associated genes were performed in many affected and unaffected members of the family. In addition, a trio whole-genome sequencing was performed to find a potential explanation of phenotypic variability. Neuropathologic analysis was performed in a single affected family member. RESULTS The clinical phenotype was characterized by 3 different syndromes-1 with rapidly progressive dystonia-parkinsonism with cognitive deterioration, 1 with mild parkinsonism associated with dementia, and 1 with predominantly psychiatric symptoms along with movement disorder. A heterozygous stop-gain variation in the C19Orf12 gene segregated with the phenotype. Targeted sequencing of all known NBIA genes, and MLPA of PLA2G6 and PANK2 genes, as well as whole-genome sequencing in a trio from the family, revealed a unique constellation of oligogenic burden in 3 NBIA-associated genes (C19Orf12 p.Trp112Ter, CP p.Val105PhefsTer5, and PLA2G6 dup(ex14)). Neuropathologic analysis of a single case (39-year-old man) showed a complex pattern of alpha-synucleinopathy and tauopathy, both involving subcortical and cortical areas and the hippocampus. CONCLUSIONS Our study expands the number of cases reported with autosomal dominant mitochondrial membrane protein-associated neurodegeneration and emphasizes the complexity of the genetic architecture, which might contribute to intrafamilial phenotypic variability.
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Affiliation(s)
- Peter Balicza
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Renata Bencsik
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Andras Lengyel
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Aniko Gal
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Zoltan Grosz
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Dora Csaban
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Gabor Rudas
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Krisztina Danics
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Gabor G Kovacs
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
| | - Maria Judit Molnar
- Institute of Genomic Medicine and Rare Diseases (P.B., R.B., A.L., A.G., Z.G., D.C., M.J.M.), Semmelweis University, Budapest, Hungary; Neurology Outpatient Clinic (A.L.), General Medical Clinic, Motala Hospital, Sweden; Department of Neuroradiology (G.R.), and Department of Forensic and Insurance Medicine (K.D.), Semmelweis University, Budapest, Hungary; Tanz Centre for Research in Neurodegenerative Disease (G.G.K.), and Department of Laboratory Medicine and Pathobiology (G.G.K.), University of Toronto; and Laboratory Medicine Program (G.G.K.), University Health Network, Toronto, Canada
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5
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Guo YP, Tang BS, Guo JF. PLA2G6-Associated Neurodegeneration (PLAN): Review of Clinical Phenotypes and Genotypes. Front Neurol 2018; 9:1100. [PMID: 30619057 PMCID: PMC6305538 DOI: 10.3389/fneur.2018.01100] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 12/03/2018] [Indexed: 12/18/2022] Open
Abstract
Phospholipase A2 group VI (PLA2G6)-associated neurodegeneration (PLAN) includes a series of neurodegenerative diseases that result from the mutations in PLA2G6. PLAN has genetic and clinical heterogeneity, with different mutation sites, mutation types and ethnicities and its clinical phenotype is different. The clinical phenotypes and genotypes of PLAN are closely intertwined and vary widely. PLA2G6 encodes a group of VIA calcium-independent phospholipase A2 proteins (iPLA2β), an enzyme involved in lipid metabolism. According to the age of onset and progressive clinical features, PLAN can be classified into the following subtypes: infantile neuroaxonal dystrophy (INAD), atypical neuroaxonal dystrophy (ANAD) and parkinsonian syndrome which contains adult onset dystonia parkinsonism (DP) and autosomal recessive early-onset parkinsonism (AREP). In this review, we present an overview of PLA2G6-associated neurodegeneration in the context of current research.
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Affiliation(s)
- Yu-Pei Guo
- Center for Brain Disorders Research, Capital Medical University and Beijing Institute of Brain Disorders, Beijing, China.,Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Bei-Sha Tang
- Center for Brain Disorders Research, Capital Medical University and Beijing Institute of Brain Disorders, Beijing, China.,Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Center for Medical Genetics, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
| | - Ji-Feng Guo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Center for Medical Genetics, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
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6
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Blake RB, Gilbert DL, Schapiro MB. Child Neurology: Two sisters with dystonia and regression: PLA2G6-associated neurodegeneration. Neurology 2018; 87:e1-3. [PMID: 27378808 DOI: 10.1212/wnl.0000000000002804] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Robert B Blake
- From the Department of Neurology, Cincinnati Children's Hospital Medical Center, OH.
| | - Donald L Gilbert
- From the Department of Neurology, Cincinnati Children's Hospital Medical Center, OH
| | - Mark B Schapiro
- From the Department of Neurology, Cincinnati Children's Hospital Medical Center, OH
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7
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Ferese R, Scala S, Biagioni F, Giardina E, Zampatti S, Modugno N, Colonnese C, Storto M, Fornai F, Novelli G, Ruggieri S, Gambardella S. Heterozygous PLA2G6 Mutation Leads to Iron Accumulation Within Basal Ganglia and Parkinson's Disease. Front Neurol 2018; 9:536. [PMID: 30042723 PMCID: PMC6048271 DOI: 10.3389/fneur.2018.00536] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 06/18/2018] [Indexed: 12/11/2022] Open
Abstract
Mutations of PLA2G6 gene are responsible for PARK14, an autosomal recessive L-DOPA responsive dystonia/parkinsonism with early/adult onset. This phenotype possesses an high clinical variability, which consists in the occurrence of cerebral and cerebellar atrophy, iron accumulation in the basal ganglia, and cognitive decline. This report describes a PD patient carrying an heterozygous PLA2G6 mutation, which was identified also in his PD affected sister. This patient is characterized by a L-DOPA responsive typical parkinsonian syndrome without the occurrence of dystonia, a slight cognitive decline, presence of iron accumulation both in neo and paleostriatum while cerebellar atrophy was absent. Clinical and imaging features are compatible with the PARK14 phenotype. Although PARK14 has been previously reported to be inherited as a recessive disorder, clinical and genetic analysis of this proband and his family rise the hypothesis that even heterozygous PLA2G6 mutations may cause PARK14. It remains to be analyzed whether these heterozygous variants may act as dominant mutations, or they merely increase the risk to develop PD by acting within a context of synergistic genetic and/or environmental backgrounds.
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Affiliation(s)
| | | | | | - Emiliano Giardina
- Molecular Genetics Laboratory UILDM, Santa Lucia Foundation, Rome, Italy.,Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Stefania Zampatti
- IRCCS Neuromed, Pozzilli, Italy.,Molecular Genetics Laboratory UILDM, Santa Lucia Foundation, Rome, Italy
| | | | - Claudio Colonnese
- IRCCS Neuromed, Pozzilli, Italy.,DAI Neurology and Psichiatry, Department of Neuroradiology, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | | | - Francesco Fornai
- IRCCS Neuromed, Pozzilli, Italy.,Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Giuseppe Novelli
- IRCCS Neuromed, Pozzilli, Italy.,Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
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8
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Pena LDM, Jiang YH, Schoch K, Spillmann RC, Walley N, Stong N, Horn SR, Sullivan JA, McConkie-Rosell A, Kansagra S, Smith EC, El-Dairi M, Bellet J, Ann Keels M, Jasien J, Kranz PG, Noel R, Nagaraj SK, Lark RK, Wechsler DSG, del Gaudio D, Leung ML, Hendon LG, Parker CC, Jones KL, Goldstein DB, Shashi V. Looking beyond the exome: a phenotype-first approach to molecular diagnostic resolution in rare and undiagnosed diseases. Genet Med 2018; 20:464-469. [PMID: 28914269 PMCID: PMC5851806 DOI: 10.1038/gim.2017.128] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 06/16/2017] [Indexed: 12/01/2022] Open
Abstract
PurposeTo describe examples of missed pathogenic variants on whole-exome sequencing (WES) and the importance of deep phenotyping for further diagnostic testing.MethodsGuided by phenotypic information, three children with negative WES underwent targeted single-gene testing.ResultsIndividual 1 had a clinical diagnosis consistent with infantile systemic hyalinosis, although WES and a next-generation sequencing (NGS)-based ANTXR2 test were negative. Sanger sequencing of ANTXR2 revealed a homozygous single base pair insertion, previously missed by the WES variant caller software. Individual 2 had neurodevelopmental regression and cerebellar atrophy, with no diagnosis on WES. New clinical findings prompted Sanger sequencing and copy number testing of PLA2G6. A novel homozygous deletion of the noncoding exon 1 (not included in the WES capture kit) was detected, with extension into the promoter, confirming the clinical suspicion of infantile neuroaxonal dystrophy. Individual 3 had progressive ataxia, spasticity, and magnetic resonance image changes of vanishing white matter leukoencephalopathy. An NGS leukodystrophy gene panel and WES showed a heterozygous pathogenic variant in EIF2B5; no deletions/duplications were detected. Sanger sequencing of EIF2B5 showed a frameshift indel, probably missed owing to failure of alignment.ConclusionThese cases illustrate potential pitfalls of WES/NGS testing and the importance of phenotype-guided molecular testing in yielding diagnoses.
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Affiliation(s)
- Loren DM Pena
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
| | - Yong-Hui Jiang
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
| | - Kelly Schoch
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
| | - Rebecca C. Spillmann
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
| | - Nicole Walley
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
| | - Nicholas Stong
- Institute of Genomic Medicine, Columbia University, New York, N.Y
| | | | - Jennifer A. Sullivan
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
| | - Allyn McConkie-Rosell
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
| | - Sujay Kansagra
- Division of Neurology, Department of Pediatrics, Duke University Medical Center
| | - Edward C. Smith
- Division of Neurology, Department of Pediatrics, Duke University Medical Center
| | - Mays El-Dairi
- Department of Ophthalmology, Duke University Medical Center
| | - Jane Bellet
- Departments of Dermatology and Pediatrics, Duke University Medical Center
| | - Martha Ann Keels
- Departments of Pediatrics and Surgery, Duke University Medical Center
| | - Joan Jasien
- Division of Neurology, Department of Pediatrics, Duke University Medical Center
| | - Peter G. Kranz
- Division of Neuroradiology, Department of Radiology, Duke University Medical Center
| | - Richard Noel
- Division of Gastroenterology, Department of Pediatrics, Duke University Medical Center
| | - Shashi K. Nagaraj
- Division of Pediatric Nephrology, Department of Pediatrics, Duke University Medical Center
| | - Robert K. Lark
- Department of Orthopedic Surgery, Duke University Medical Center
| | - Daniel SG Wechsler
- Division of Pediatric Hematology-Oncology, Department of Pediatrics, Duke University Medical Center
| | | | - Marco L. Leung
- Department of Human Genetics, University of Chicago, Chicago Ill
| | - Laura G. Hendon
- Division of Maternal Fetal Medicine, University of Mississippi Medical Center, Jackson, Miss
| | - Collette C. Parker
- Division of Child Neurology, Department of Pediatrics, University of Mississippi Medical Center
| | - Kelly L. Jones
- Division of Medical Genetics, Department of Pediatrics, University of Mississippi Medical Center
| | | | | | - Vandana Shashi
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center
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9
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Iannello G, Graziano C, Cenacchi G, Cordelli DM, Zuntini R, Papa V, Magistà AM, Gagliardi M, Procopio R, Quattrone A, Annesi G. A new PLA2G6 mutation in a family with infantile neuroaxonal dystrophy. J Neurol Sci 2017; 381:209-212. [DOI: 10.1016/j.jns.2017.08.3260] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 07/14/2017] [Accepted: 08/24/2017] [Indexed: 11/17/2022]
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10
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PARK14 PLA2G6 mutants are defective in preventing rotenone-induced mitochondrial dysfunction, ROS generation and activation of mitochondrial apoptotic pathway. Oncotarget 2017; 8:79046-79060. [PMID: 29108286 PMCID: PMC5668019 DOI: 10.18632/oncotarget.20893] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 08/17/2017] [Indexed: 11/25/2022] Open
Abstract
Mutations in the gene encoding Ca2+-independent phospholipase A2 group 6 (PLA2G6) cause the recessive familial type 14 of Parkinson’s disease (PARK14). Mitochondrial dysfunction is involved in the pathogenesis of Parkinson’s disease (PD). PLA2G6 is believed to be required for maintaining mitochondrial function. In the present study, rotenone-induced cellular model of PD was used to investigate possible molecular pathogenic mechanism of PARK14 mutant PLA2G6-induced PD. Overexpression of wild-type (WT) PLA2G6 ameliorated rotenone-induced apoptotic death of SH-SY5Y dopaminergic cells. PARK14 mutant (D331Y), (G517C), (T572I), (R632W), (N659S) or (R741Q) PLA2G6 failed to prevent rotenone-induced activation of mitochondrial apoptotic pathway and exert a neuroprotective effect. WT PLA2G6, but not PARK14 mutant PLA2G6, prevented rotenone-induced mitophagy impairment. In contrast to WT PLA2G6, PARK14 mutant PLA2G6 was ineffective in attenuating rotenone-induced decrease in mitochondrial membrane potential and increase in the level of mitochondrial superoxide. WT PLA2G6, but not PARK14 PLA2G6 mutants, restored enzyme activity of mitochondrial complex I and cellular ATP content in rotenone-treated SH-SY5Y dopaminergic cells. In contrast to WT PLA2G6, PARK14 mutant PLA2G6 failed to prevent rotenone-induced mitochondrial lipid peroxidation and cytochrome c release. These results suggest that PARK14 PLA2G6 mutants lose their ability to maintain mitochondrial function and are defective inpreventing mitochondrial dysfunction, ROS production and activation of mitochondrial apoptotic pathway in rotenone-induced cellular model of PD.
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Iodice A, Spagnoli C, Salerno GG, Frattini D, Bertani G, Bergonzini P, Pisani F, Fusco C. Infantile neuroaxonal dystrophy and PLA2G6-associated neurodegeneration: An update for the diagnosis. Brain Dev 2017; 39:93-100. [PMID: 27884548 DOI: 10.1016/j.braindev.2016.08.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 08/29/2016] [Accepted: 08/30/2016] [Indexed: 11/25/2022]
Abstract
Infantile neuroaxonal dystrophy is a rare neurodegenerative disorder characterized by infantile onset of rapid motor and cognitive regression and hypotonia evolving into spasticity. Recessively inherited mutations of the PLA2G6 gene are causative of infantile neuroaxonal dystrophy and other PLA2G6-associated neurodegeneration, which includes conditions known as atypical neuroaxonal dystrophy, Karak syndrome and early-onset dystonia-parkinsonism with cognitive impairment. Phenotypic spectrum continues to evolve and genotype-phenotype correlations are currently limited. Due to the overlapping phenotypes and heterogeneity of clinical findings characterization of the syndrome is not always achievable. We reviewed the most recent clinical and neuroradiological information in the way to make easier differential diagnosis with other degenerative disorders in the paediatric age. Recognizing subtle signs and symptoms is a fascinating challenge to drive towards better diagnostic and genetic investigations.
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Affiliation(s)
- Alessandro Iodice
- Child Neurology Unit, Arcispedale Santa Maria Nuova Hospital - IRCCS, Reggio Emilia, Italy.
| | - Carlotta Spagnoli
- Child Neurology Unit, Arcispedale Santa Maria Nuova Hospital - IRCCS, Reggio Emilia, Italy
| | | | - Daniele Frattini
- Child Neurology Unit, Arcispedale Santa Maria Nuova Hospital - IRCCS, Reggio Emilia, Italy
| | - Gianna Bertani
- Child Neurology Unit, Arcispedale Santa Maria Nuova Hospital - IRCCS, Reggio Emilia, Italy
| | - Patrizia Bergonzini
- Pediatric Neurology Unit, Department of Mother & Child, University Hospital of Modena, Italy
| | - Francesco Pisani
- Child Neuropsychiatry Unit, Neuroscience Department, University of Parma, Italy
| | - Carlo Fusco
- Child Neurology Unit, Arcispedale Santa Maria Nuova Hospital - IRCCS, Reggio Emilia, Italy
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12
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Yamashita C, Funayama M, Li Y, Yoshino H, Yamada H, Seino Y, Tomiyama H, Hattori N. Mutation screening of PLA2G6 in Japanese patients with early onset dystonia-parkinsonism. J Neural Transm (Vienna) 2016; 124:431-435. [DOI: 10.1007/s00702-016-1658-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 11/21/2016] [Indexed: 11/21/2022]
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13
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Kapoor S, Shah MH, Singh N, Rather MI, Bhat V, Gopinath S, Bindu PS, Taly AB, Sinha S, Nagappa M, Bharath RD, Mahadevan A, Narayanappa G, Chickabasaviah YT, Kumar A. Genetic Analysis of PLA2G6 in 22 Indian Families with Infantile Neuroaxonal Dystrophy, Atypical Late-Onset Neuroaxonal Dystrophy and Dystonia Parkinsonism Complex. PLoS One 2016; 11:e0155605. [PMID: 27196560 PMCID: PMC4873246 DOI: 10.1371/journal.pone.0155605] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 05/02/2016] [Indexed: 12/02/2022] Open
Abstract
Mutations in PLA2G6 were identified in patients with a spectrum of neurodegenerative conditions, such as infantile neuroaxonal dystrophy (INAD), atypical late-onset neuroaxonal dystrophy (ANAD) and dystonia parkinsonism complex (DPC). However, there is no report on the genetic analysis of families with members affected with INAD, ANAD and DPC from India. Therefore, the main aim of this study was to perform genetic analysis of 22 Indian families with INAD, ANAD and DPC. DNA sequence analysis of the entire coding region of PLA2G6 identified 13 different mutations, including five novel ones (p.Leu224Pro, p.Asp283Asn, p.Arg329Cys, p.Leu491Phe, and p.Arg649His), in 12/22 (54.55%) families with INAD and ANAD. Interestingly, one patient with INAD was homozygous for two different mutations, p.Leu491Phe and p.Ala516Val, and thus harboured four mutant alleles. With these mutations, the total number of mutations in this gene reaches 129. The absence of mutations in 10/22 (45.45%) families suggests that the mutations could be in deep intronic or promoter regions of this gene or these families could have mutations in a yet to be identified gene. The present study increases the mutation landscape of PLA2G6. The present finding will be useful for genetic diagnosis, carrier detection and genetic counselling to families included in this study and other families with similar disease condition.
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Affiliation(s)
- Saketh Kapoor
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, 560012, India
| | - Mohd Hussain Shah
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, 560012, India
| | - Nivedita Singh
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, 560012, India
| | - Mohammad Iqbal Rather
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, 560012, India
| | - Vishwanath Bhat
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, 560012, India
| | - Sindhura Gopinath
- Department of Biotechnology, R.V. College of Engineering, Bangalore, 560059, India
| | - Parayil Sankaran Bindu
- Department of Neurology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
- * E-mail: (AK); (PSB)
| | - Arun B. Taly
- Department of Neurology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Sanjib Sinha
- Department of Neurology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Madhu Nagappa
- Department of Neurology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Rose Dawn Bharath
- Department of Neuroimaging and Interventional Radiology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Anita Mahadevan
- Department of Neuropathology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Gayathri Narayanappa
- Department of Neuropathology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Yasha T. Chickabasaviah
- Department of Neuropathology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Arun Kumar
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, 560012, India
- * E-mail: (AK); (PSB)
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14
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Davids M, Kane MS, He M, Wolfe LA, Li X, Raihan MA, Chao KR, Bone WP, Boerkoel CF, Gahl WA, Toro C. Disruption of Golgi morphology and altered protein glycosylation in PLA2G6-associated neurodegeneration. J Med Genet 2015; 53:180-9. [PMID: 26668131 DOI: 10.1136/jmedgenet-2015-103338] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 11/09/2015] [Indexed: 01/07/2023]
Abstract
BACKGROUND Mutations in PLA2G6, which encodes the calcium-independent phospholipase A2 group VI, cause neurodegeneration and diffuse cortical Lewy body formation by a yet undefined mechanism. We assessed whether altered protein glycosylation due to abnormal Golgi morphology might be a factor in the pathology of this disease. METHODS Three patients presented with PLA2G6-associated neurodegeneration (PLAN); two had infantile neuroaxonal dystrophy (INAD) and one had adult-onset dystonia-parkinsonism. We analysed protein N-linked and O-linked glycosylation in cerebrospinal fluid, plasma, urine, and cultured skin fibroblasts using high performance liquid chromatography (HPLC) and matrix-assisted laser desorption ionization--time of flight/mass spectrometry (MALDI-TOF/MS). We also assessed sialylation and Golgi morphology in cultured fibroblasts by immunofluorescence and performed rescue experiments using a lentiviral vector. RESULTS The patients with INAD had PLA2G6 mutations NM_003560.2: c.[950G>T];[426-1077dup] and c.[1799G>A];[2221C>T] and the patient with dystonia-parkinsonism had PLA2G6 mutations NM_003560.2: c.[609G>A];[2222G>A]. All three patients had altered Golgi morphology and abnormalities of protein O-linked glycosylation and sialylation in cultured fibroblasts that were rescued by lentiviral overexpression of wild type PLA2G6. CONCLUSIONS Our findings add altered Golgi morphology, O-linked glycosylation and sialylation defects to the phenotypical spectrum of PLAN; these pathways are essential for correct processing and distribution of proteins. Lewy body and Tau pathology, two neuropathological features of PLAN, could emerge from these defects. Therefore, Golgi morphology, O-linked glycosylation and sialylation may play a role in the pathogenesis of PLAN and perhaps other neurodegenerative disorders.
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Affiliation(s)
- Mariska Davids
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Megan S Kane
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Miao He
- Department of Pathology and Laboratory of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA The Michael J Palmieri Metabolic Laboratory, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Lynne A Wolfe
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Xueli Li
- Department of Pathology and Laboratory of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA The Michael J Palmieri Metabolic Laboratory, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Mohd A Raihan
- Department of Pathology and Laboratory of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA The Michael J Palmieri Metabolic Laboratory, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Katherine R Chao
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - William P Bone
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Cornelius F Boerkoel
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - William A Gahl
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Camilo Toro
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, Maryland, USA Office of the Clinical Director, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
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15
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Ramanadham S, Ali T, Ashley JW, Bone RN, Hancock WD, Lei X. Calcium-independent phospholipases A2 and their roles in biological processes and diseases. J Lipid Res 2015; 56:1643-68. [PMID: 26023050 DOI: 10.1194/jlr.r058701] [Citation(s) in RCA: 135] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Indexed: 12/24/2022] Open
Abstract
Among the family of phospholipases A2 (PLA2s) are the Ca(2+)-independent PLA2s (iPLA2s) and they are designated group VI iPLA2s. In relation to secretory and cytosolic PLA2s, the iPLA2s are more recently described and details of their expression and roles in biological functions are rapidly emerging. The iPLA2s or patatin-like phospholipases (PNPLAs) are intracellular enzymes that do not require Ca(2+) for activity, and contain lipase (GXSXG) and nucleotide-binding (GXGXXG) consensus sequences. Though nine PNPLAs have been recognized, PNPLA8 (membrane-associated iPLA2γ) and PNPLA9 (cytosol-associated iPLA2β) are the most widely studied and understood. The iPLA2s manifest a variety of activities in addition to phospholipase, are ubiquitously expressed, and participate in a multitude of biological processes, including fat catabolism, cell differentiation, maintenance of mitochondrial integrity, phospholipid remodeling, cell proliferation, signal transduction, and cell death. As might be expected, increased or decreased expression of iPLA2s can have profound effects on the metabolic state, CNS function, cardiovascular performance, and cell survival; therefore, dysregulation of iPLA2s can be a critical factor in the development of many diseases. This review is aimed at providing a general framework of the current understanding of the iPLA2s and discussion of the potential mechanisms of action of the iPLA2s and related involved lipid mediators.
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Affiliation(s)
- Sasanka Ramanadham
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Tomader Ali
- Undergraduate Research Office, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Jason W Ashley
- Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA 19104
| | - Robert N Bone
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - William D Hancock
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Xiaoyong Lei
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
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16
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Sumi-Akamaru H, Beck G, Kato S, Mochizuki H. Neuroaxonal dystrophy inPLA2G6knockout mice. Neuropathology 2015; 35:289-302. [DOI: 10.1111/neup.12202] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Accepted: 01/25/2015] [Indexed: 12/19/2022]
Affiliation(s)
- Hisae Sumi-Akamaru
- Department of Neurology; Osaka University Graduate School of Medicine; Suita Japan
| | - Goichi Beck
- Department of Neurology; Osaka University Graduate School of Medicine; Suita Japan
| | - Shinsuke Kato
- Division of Neuropathology; Department of Brain and Neurosciences; Tottori University Faculty of Medicine; Yonago Japan
| | - Hideki Mochizuki
- Department of Neurology; Osaka University Graduate School of Medicine; Suita Japan
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17
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Romani M, Kraoua I, Micalizzi A, Klaa H, Benrhouma H, Drissi C, Turki I, Castellana S, Mazza T, Valente EM, Gouider-Khouja N. Infantile and childhood onsetPLA2G6-associated neurodegeneration in a large North African cohort. Eur J Neurol 2014; 22:178-86. [DOI: 10.1111/ene.12552] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 07/11/2014] [Indexed: 11/30/2022]
Affiliation(s)
- M. Romani
- IRCCS Casa Sollievo della Sofferenza; Mendel Laboratory; San Giovanni Rotondo Italy
| | - I. Kraoua
- Research Unit 06/11 and Department of Child and Adolescent Neurology; National Institute Mongi Ben Hmida of Neurology; Tunis Tunisia
| | - A. Micalizzi
- IRCCS Casa Sollievo della Sofferenza; Mendel Laboratory; San Giovanni Rotondo Italy
- Department of Medical and Surgical Pediatric Sciences; University of Messina; Messina Italy
| | - H. Klaa
- Research Unit 06/11 and Department of Child and Adolescent Neurology; National Institute Mongi Ben Hmida of Neurology; Tunis Tunisia
| | - H. Benrhouma
- Research Unit 06/11 and Department of Child and Adolescent Neurology; National Institute Mongi Ben Hmida of Neurology; Tunis Tunisia
| | - C. Drissi
- Department of Neuroradiology; National Institute Mongi Ben Hmida of Neurology; Tunis Tunisia
| | - I. Turki
- Research Unit 06/11 and Department of Child and Adolescent Neurology; National Institute Mongi Ben Hmida of Neurology; Tunis Tunisia
| | - S. Castellana
- IRCCS Casa Sollievo della Sofferenza; Mendel Laboratory; San Giovanni Rotondo Italy
| | - T. Mazza
- IRCCS Casa Sollievo della Sofferenza; Mendel Laboratory; San Giovanni Rotondo Italy
| | - E. M. Valente
- IRCCS Casa Sollievo della Sofferenza; Mendel Laboratory; San Giovanni Rotondo Italy
- Section of Neurosciences; Department of Medicine and Surgery; University of Salerno; Salerno Italy
| | - N. Gouider-Khouja
- Research Unit 06/11 and Department of Child and Adolescent Neurology; National Institute Mongi Ben Hmida of Neurology; Tunis Tunisia
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18
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Cif L, Kurian MA, Gonzalez V, Garcia‐Ptacek S, Roujeau T, Gelisse P, Moura de Ribeiro AM, Crespel A, MacPherson L, Coubes P. Atypical PLA2G6-Associated Neurodegeneration: Social Communication Impairment, Dystonia and Response to Deep Brain Stimulation. Mov Disord Clin Pract 2014; 1:128-131. [PMID: 30363890 PMCID: PMC6183017 DOI: 10.1002/mdc3.12030] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 03/21/2014] [Accepted: 03/28/2014] [Indexed: 11/10/2022] Open
Affiliation(s)
- Laura Cif
- Département de NeurochirurgieCHRU MontpellierHôpital Gui de ChauliacMontpellierFrance
- INSERM, U661MontpellierFrance
- Université de Montpellier 1MontpellierFrance
- CNRS UMR5203Institut de Génomique FonctionnelleMontpellierFrance
- Département des Neurosciences CliniquesLaboratoire de Recherche en NeuroimagerieCentre Hospitalier Universitaire VaudoisUniversité de LausanneLausanneSwitzerland
| | - Manju A. Kurian
- Neurosciences UnitInstitute of Child Health, LondonUnited Kingdom
- Department of NeurologyGreat Ormond Street HospitalLondonUnited Kingdom
| | - Victoria Gonzalez
- Département de NeurochirurgieCHRU MontpellierHôpital Gui de ChauliacMontpellierFrance
- INSERM, U661MontpellierFrance
- Université de Montpellier 1MontpellierFrance
- CNRS UMR5203Institut de Génomique FonctionnelleMontpellierFrance
| | - Sara Garcia‐Ptacek
- Department of NeurobiologyCare Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Thomas Roujeau
- Département de NeurochirurgieCHRU MontpellierHôpital Gui de ChauliacMontpellierFrance
| | - Philippe Gelisse
- Epilepsy UnitUniversity Hospital of MontpellierMontpellierFrance
| | | | - Arielle Crespel
- Epilepsy UnitUniversity Hospital of MontpellierMontpellierFrance
| | - Lesley MacPherson
- Department of RadiologyBirmingham Children's HospitalBirminghamUnited Kingdom
| | - Philippe Coubes
- Département de NeurochirurgieCHRU MontpellierHôpital Gui de ChauliacMontpellierFrance
- INSERM, U661MontpellierFrance
- Université de Montpellier 1MontpellierFrance
- CNRS UMR5203Institut de Génomique FonctionnelleMontpellierFrance
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19
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Illingworth MA, Meyer E, Chong WK, Manzur AY, Carr LJ, Younis R, Hardy C, McDonald F, Childs AM, Stewart B, Warren D, Kneen R, King MD, Hayflick SJ, Kurian MA. PLA2G6-associated neurodegeneration (PLAN): further expansion of the clinical, radiological and mutation spectrum associated with infantile and atypical childhood-onset disease. Mol Genet Metab 2014; 112:183-9. [PMID: 24745848 PMCID: PMC4048546 DOI: 10.1016/j.ymgme.2014.03.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 03/21/2014] [Indexed: 11/18/2022]
Abstract
Phospholipase A2 associated neurodegeneration (PLAN) is a major phenotype of autosomal recessive Neurodegeneration with Brain Iron Accumulation (NBIA). We describe the clinical phenotypes, neuroimaging features and PLA2G6 mutations in 5 children, of whom 4 presented with infantile neuroaxonal dystrophy (INAD). One other patient was diagnosed with the onset of PLAN in childhood, and our report highlights the diagnostic challenges associated with this atypical PLAN subtype. In this series, the neuroradiological relevance of classical PLAN features as well as apparent claval hypertrophy' is explored. Novel PLA2G6 mutations were identified in all patients. PLAN should be considered not only in patients presenting with a classic INAD phenotype but also in older patients presenting later in childhood with non-specific progressive neurological features including social communication difficulties, gait disturbance, dyspraxia, neuropsychiatric symptoms and extrapyramidal motor features.
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Affiliation(s)
- M A Illingworth
- Department of Neurology, Great Ormond Street Hospital, London, UK
| | - E Meyer
- Neurosciences Unit, UCL-Institute of Child Health, London, UK
| | - W K Chong
- Department of Radiology, Great Ormond Street Hospital, London, UK
| | - A Y Manzur
- Dubowitz Neuromuscular Centre for Congenital Muscular Dystrophies and Myopathies, Great Ormond Street Hospital, London, UK
| | - L J Carr
- Department of Neurology, Great Ormond Street Hospital, London, UK
| | - R Younis
- West Midlands Regional Genetics, Birmingham Women's Hospital, Birmingham, UK
| | - C Hardy
- West Midlands Regional Genetics, Birmingham Women's Hospital, Birmingham, UK
| | - F McDonald
- West Midlands Regional Genetics, Birmingham Women's Hospital, Birmingham, UK
| | - A M Childs
- Department of Paediatric Neurology, Leeds General Infirmary, Leeds, UK
| | - B Stewart
- Department of Paediatrics, York Teaching Hospitals NHS Foundation Trust, York, UK
| | - D Warren
- Department of Neuroradiology, Leeds teaching Hospitals, Leeds. UK
| | - R Kneen
- Department of Neurology, Alder Hey Children's Hospital, Liverpool, UK
| | - M D King
- Department of Paediatric Neurology, Children's University Hospital, Temple Street, Dublin, Ireland
| | - S J Hayflick
- Department of Molecular & Medical Genetics, OR Health & Science University, Portland 97239, USA; Department of Paediatrics, OR Health & Science University, Portland 97239, USA; Department of Neurology, OR Health & Science University, Portland 97239, USA
| | - M A Kurian
- Department of Neurology, Great Ormond Street Hospital, London, UK; Neurosciences Unit, UCL-Institute of Child Health, London, UK.
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20
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Levi S, Finazzi D. Neurodegeneration with brain iron accumulation: update on pathogenic mechanisms. Front Pharmacol 2014; 5:99. [PMID: 24847269 PMCID: PMC4019866 DOI: 10.3389/fphar.2014.00099] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 04/17/2014] [Indexed: 12/21/2022] Open
Abstract
Perturbation of iron distribution is observed in many neurodegenerative disorders, including Alzheimer’s and Parkinson’s disease, but the comprehension of the metal role in the development and progression of such disorders is still very limited. The combination of more powerful brain imaging techniques and faster genomic DNA sequencing procedures has allowed the description of a set of genetic disorders characterized by a constant and often early accumulation of iron in specific brain regions and the identification of the associated genes; these disorders are now collectively included in the category of neurodegeneration with brain iron accumulation (NBIA). So far 10 different genetic forms have been described but this number is likely to increase in short time. Two forms are linked to mutations in genes directly involved in iron metabolism: neuroferritinopathy, associated to mutations in the FTL gene and aceruloplasminemia, where the ceruloplasmin gene product is defective. In the other forms the connection with iron metabolism is not evident at all and the genetic data let infer the involvement of other pathways: Pank2, Pla2G6, C19orf12, COASY, and FA2H genes seem to be related to lipid metabolism and to mitochondria functioning, WDR45 and ATP13A2 genes are implicated in lysosomal and autophagosome activity, while the C2orf37 gene encodes a nucleolar protein of unknown function. There is much hope in the scientific community that the study of the NBIA forms may provide important insight as to the link between brain iron metabolism and neurodegenerative mechanisms and eventually pave the way for new therapeutic avenues also for the more common neurodegenerative disorders. In this work, we will review the most recent findings in the molecular mechanisms underlining the most common forms of NBIA and analyze their possible link with brain iron metabolism.
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Affiliation(s)
- Sonia Levi
- Proteomic of Iron Metabolism, Vita-Salute San Raffaele University Milano, Italy ; San Raffaele Scientific Institute Milano, Italy
| | - Dario Finazzi
- Department of Molecular and Translational Medicine, University of Brescia Brescia, Italy ; Spedali Civili di Brescia Brescia, Italy
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21
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Abstract
The Neuroaxonal Dystrophies (NADs) are a group of clinically and genetically heterogeneous neurodegenerative conditions. These disorders show the unique pathological feature of neuroaxonal dystrophy (NAD): axonal swelling (spheroids) localized throughout the central nervous and peripheral nervous systems. NADs are also morphologically characterized by iron accumulation in the basal ganglia; and are now included in the group of diseases called neurodegeneration with brain iron accumulation (NBIA). NADs comprise two main diseases: pantothenate-kinase associated neurodegeneration (PKAN) and infantile neuroaxonal dystrophy (INAD). PKAN in caused by mutation in the PANK-2 gene. In classic PKAN onset of disease is in the first decade and patients show dystonia, rigidity and dysarthria; course is progressive leading to loss of autonomous gait within 15 years. In atypical PKAN age at onset is later and progression slower. Psychiatric symptoms, obsessive-compulsive disorder, and tourettism may be prominent. In classic INAD patients present with psychomotor regression between 6 months-3 years, followed by neurological deterioration leading to tetraparesis, optic atrophy, and dementia. Atypical NAD refers to all patients who differ from the classical phenotype in term of age at onset and disease progression. Mutations in PLA2G6 gene are found both in classic and atypical INAD patients.
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22
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Lei X, Bone RN, Ali T, Wohltmann M, Gai Y, Goodwin KJ, Bohrer AE, Turk J, Ramanadham S. Genetic modulation of islet β-cell iPLA₂β expression provides evidence for its impact on β-cell apoptosis and autophagy. Islets 2013; 5:29-44. [PMID: 23411472 PMCID: PMC3662380 DOI: 10.4161/isl.23758] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
β-cell apoptosis is a significant contributor to β-cell dysfunction in diabetes and ER stress is among the factors that contributes to β-cell death. We previously identified that the Ca²⁺-independent phospholipase A₂β (iPLA₂β), which in islets is localized in β-cells, participates in ER stress-induced β-cell apoptosis. Here, direct assessment of iPLA₂β role was made using β-cell-specific iPLA₂β overexpressing (RIP-iPLA₂β-Tg) and globally iPLA₂β-deficient (iPLA₂β-KO) mice. Islets from Tg, but not KO, express higher islet iPLA₂β and neutral sphingomyelinase, decrease in sphingomyelins, and increase in ceramides, relative to WT group. ER stress induces iPLA₂β, ER stress factors, loss of mitochondrial membrane potential (∆Ψ), caspase-3 activation, and β-cell apoptosis in the WT and these are all amplified in the Tg group. Surprisingly, β-cells apoptosis while reduced in the KO is higher than in the WT group. This, however, was not accompanied by greater caspase-3 activation but with larger loss of ∆Ψ, suggesting that iPLA₂β deficiency impacts mitochondrial membrane integrity and causes apoptosis by a caspase-independent manner. Further, autophagy, as reflected by LC3-II accumulation, is increased in Tg and decreased in KO, relative to WT. Our findings suggest that (1) iPLA₂β impacts upstream (UPR) and downstream (ceramide generation and mitochondrial) pathways in β-cells and (2) both over- or under-expression of iPLA₂β is deleterious to the β-cells. Further, we present for the first time evidence for potential regulation of autophagy by iPLA₂β in islet β-cells. These findings support the hypothesis that iPLA₂β induction under stress, as in diabetes, is a key component to amplifying β-cell death processes.
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Affiliation(s)
- Xiaoyong Lei
- Department of Cell, Developmental, and Integrative Biology; University of Alabama at Birmingham; Birmingham, AL USA
| | - Robert N. Bone
- Department of Pathology; University of Alabama at Birmingham; Birmingham, AL USA
| | - Tomader Ali
- Department of Cell, Developmental, and Integrative Biology; University of Alabama at Birmingham; Birmingham, AL USA
| | - Mary Wohltmann
- Department of Medicine; Mass Spectrometry Resource; Division of Endocrinology, Metabolism and Lipid Research; Washington University School of Medicine; St. Louis, MO USA
| | - Ying Gai
- Department of Cell, Developmental, and Integrative Biology; University of Alabama at Birmingham; Birmingham, AL USA
| | - Karen J. Goodwin
- Department of Cell, Developmental, and Integrative Biology; University of Alabama at Birmingham; Birmingham, AL USA
| | - Alan E. Bohrer
- Department of Medicine; Mass Spectrometry Resource; Division of Endocrinology, Metabolism and Lipid Research; Washington University School of Medicine; St. Louis, MO USA
| | - John Turk
- Department of Medicine; Mass Spectrometry Resource; Division of Endocrinology, Metabolism and Lipid Research; Washington University School of Medicine; St. Louis, MO USA
| | - Sasanka Ramanadham
- Department of Cell, Developmental, and Integrative Biology; University of Alabama at Birmingham; Birmingham, AL USA
- Correspondence to: Sasanka Ramanadham,
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23
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Kurian MA, Hayflick SJ. Pantothenate kinase-associated neurodegeneration (PKAN) and PLA2G6-associated neurodegeneration (PLAN): review of two major neurodegeneration with brain iron accumulation (NBIA) phenotypes. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2013; 110:49-71. [PMID: 24209433 PMCID: PMC6059649 DOI: 10.1016/b978-0-12-410502-7.00003-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Neurodegeneration with brain iron accumulation (NBIA) comprises a heterogeneous group of disorders characterized by the presence of radiologically discernible high brain iron, particularly within the basal ganglia. A number of childhood NBIA syndromes are described, of which two of the major subtypes are pantothenate kinase-associated neurodegeneration (PKAN) and PLA2G6-associated neurodegeneration (PLAN). PKAN and PLAN are autosomal recessive NBIA disorders due to mutations in PANK2 and PLA2G6, respectively. Presentation is usually in childhood, with features of neurological regression and motor dysfunction. In both PKAN and PLAN, a number of classical and atypical phenotypes are reported. In this chapter, we describe the clinical, radiological, and genetic features of these two disorders and also discuss the pathophysiological mechanisms postulated to play a role in disease pathogenesis.
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Affiliation(s)
- Manju A Kurian
- Neurosciences Unit, UCL-Institute of Child Health, London, United Kingdom; Department of Neurology, Great Ormond Street Hospital, London, United Kingdom.
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24
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Zhang P, Gao Z, Jiang Y, Wang J, Zhang F, Wang S, Yang Y, Xiong H, Zhang Y, Bao X, Xiao J, Wu X, Wu Y. Follow-up study of 25 Chinese children with PLA2G6-associated neurodegeneration. Eur J Neurol 2012; 20:322-30. [PMID: 22934738 DOI: 10.1111/j.1468-1331.2012.03856.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 07/12/2012] [Indexed: 12/27/2022]
Abstract
BACKGROUND To perform a follow-up of 25 Chinese children with gene-confirmed PLA2G6-associated neurodegeneration (PLAN). METHODS We recruited patients with infantile neuroaxonal dystrophy (INAD) according to the criteria proposed by Nardocci et al. Follow-up was conducted from 7 months to 8 years after the first visit. The PLA2G6 gene was sequenced, and copy number variation (CNV) was detected in patients with only one mutant allele and in mutation-negative patients. Patients with late-onset PLAN until 2012 were reviewed. RESULTS All patients with INAD exhibited rapid decline in motor and mental function, consistent with previous reports from other populations. Epileptic seizures occurred in 16.7%. One teenager with late-onset PLAN was diagnosed and followed up. The age of disease onset in published late-onset PLAN ranged between 18 months and 37 years. Initial presentations included gait instability (79.0%), mood/behavior changes (10.5%), dysarthria (5.26%) and cognitive deterioration (5.3%). Compared with INAD, cerebellar atrophy (42.1%) was less frequent in the late-onset cases, with cerebral atrophy more common (71.4%). Brain iron accumulation was seen in 52.6%. PLA2G6 mutations were identified by DNA sequencing in 92.3% of clinically diagnosed INAD cases and in the late-onset case. Twenty-seven different mutations were found, of which 13 were novel. No CNVs were detected. Maternal uniparental disomy was confirmed in one INAD case. CONCLUSIONS This is the largest report on PLAN in the Chinese population. We suggest that PLA2G6 should be screened in any patient exhibiting progressive gait disturbance, bradykinesia, dysarthria, tremors, mood/behavior changes or cognitive decline, especially when associated with cerebellar atrophy and/or iron accumulation and/or cerebral atrophy.
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Affiliation(s)
- P Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing
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25
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Tian JY, Tang BS, Shi CH, Lv ZY, Li K, Yu RL, Shen L, Yan XX, Guo JF. Analysis of PLA2G6 gene mutation in sporadic early-onset parkinsonism patients from Chinese population. Neurosci Lett 2012; 514:156-8. [DOI: 10.1016/j.neulet.2012.02.078] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Revised: 01/13/2012] [Accepted: 02/23/2012] [Indexed: 11/26/2022]
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26
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Lu CS, Lai SC, Wu RM, Weng YH, Huang CL, Chen RS, Chang HC, Wu-Chou YH, Yeh TH. PLA2G6 mutations in PARK14-linked young-onset parkinsonism and sporadic Parkinson's disease. Am J Med Genet B Neuropsychiatr Genet 2012; 159B:183-91. [PMID: 22213678 DOI: 10.1002/ajmg.b.32012] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 11/30/2011] [Indexed: 11/09/2022]
Abstract
Mutations of PLA2G6 gene have been lately proposed to be the causative gene for PARK14 in patients with autosomal recessive young-onset parkinsonism (YOPD). The role of PLA2G6 mutations as a risk factor for Parkinson's disease is not clear. To study the PLA2G6 mutations in PARK14-linked patients and its association with the onset of sporadic Parkinson's disease (sPD), sequencing and gene dosage analyses were carried out in 25 patients (onset age ≦30 years) then the identified variants were assessed in 956 sporadic PD (sPD) patients and 802 age-matched healthy controls. Four genetic variants were identified; one patient had homozygous c.991G > T (p.Asp331Tyr) mutation, two had compound heterozygous c.991G > T/c.1077G > A (p.Met358IlefsX) mutation, one had single c.1976A > G (p.Asn659Ser) mutation, and one patient had an exon 1 hetero-deletion. The c.1077G > A mutation resulted in a 4-bp deletion in leukocyte mRNA by activating a cryptic splice site in exon 7. Only p.Asp331Tyr was identified in four sPD patients and four controls. The onset age for PLA2G6 mutation carriers was younger than that for sPD (29.86 ± 8.59 vs. 56.84 ± 11.33 years, P = 0.0002). The analysis of previously reported PARK14 patients revealed that those who carried a truncated mutation tended to have a complicated phenotype and atrophies of cortex and cerebellum. In conclusion, PLA2G6 mutation was the second common genetic cause after PRKN mutation in our YOPD patients and might be a risk factor for early-onset PD in Han Chinese. Additionally, mutation data should be interpreted carefully because even a synonymous mutation could cause abnormal mRNA splicing.
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Affiliation(s)
- Chin-Song Lu
- Division of Movement Disorders, Department of Neurology, Chang Gung Memorial Hospital at Linkou Medical Center, Taoyuan, Taiwan
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27
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Kurian MA, McNeill A, Lin JP, Maher ER. Childhood disorders of neurodegeneration with brain iron accumulation (NBIA). Dev Med Child Neurol 2011; 53:394-404. [PMID: 21480873 DOI: 10.1111/j.1469-8749.2011.03955.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Neurodegeneration with brain iron accumulation (NBIA) comprises a heterogeneous group of progressive complex motor disorders characterized by the presence of high brain iron, particularly within the basal ganglia. A number of autosomal recessive NBIA syndromes can present in childhood, most commonly pantothenate kinase-associated neurodegeneration (PKAN; due to mutations in the PANK2 gene) and phospholipase A2 group 6-associated neurodegeneration (PLAN; associated with genetic defects in PLA2G6). Mutations in the genes that cause these two neuroaxonal dystrophies are thought to disrupt the normal cellular functions of phospholipid remodelling and fatty acid metabolism. A significant proportion of children with an NBIA phenotype have no genetic diagnosis and there are, no doubt, additional as yet undiscovered genes that account for a number of these cases. NBIA disorders can be diagnostically challenging as there is often phenotypic overlap between the different disease entities. This review aims to define the clinical, radiological, and genetic features of such disorders, providing the clinician with a stepwise approach to appropriate neurological and genetic investigation, as well as a clinical management strategy for these neurodegenerative syndromes.
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Affiliation(s)
- Manju A Kurian
- Neurosciences Unit, Institute of Child Health (University College London) and Great Ormond Street Hospital, London, UK.
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28
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Bower MA, Bushara K, Dempsey MA, Das S, Tuite PJ. Novel mutations in siblings with later-onset PLA2G6-associated neurodegeneration (PLAN). Mov Disord 2011; 26:1768-9. [PMID: 21520282 DOI: 10.1002/mds.23617] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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