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El Otmani H, Daghi M, Tahiri Jouti N, Lesage S. An overview of the worldwide distribution of LRRK2 mutations in Parkinson's disease. Neurodegener Dis Manag 2023; 13:335-350. [PMID: 38305913 DOI: 10.2217/nmt-2023-0025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder with significant genetic influence. The LRRK2 gene is a major genetic contributor, particularly the Gly2019Ser mutation. This focused review investigates the global distribution of LRRK2 mutations, with emphasis on Gly2019Ser and other pathogenic variants. Prevalence rates of Gly2019Ser are highest in North Africa and the Ashkenazi-Jewish population, indicating a potential common ancestor and founder effect. Other LRRK2 mutations, including Asn1437His, Arg1441Gly/Cys/His, Tyr1699Cys and Ile2020Thr, exhibit varying global prevalences. Understanding these distributions enhances our knowledge of PD genetics and aids personalized medicine. Further research is crucial to unravel clinical implications and develop targeted therapies for LRRK2 mutation carriers.
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Affiliation(s)
- Hicham El Otmani
- Laboratory of Medical Genetics & Molecular Pathology. Faculty of Medicine and Pharmacy, Hassan II University, 20250, Casablanca, Morocco
- Laboratory of Cellular and Molecular Inflammatory, Degenerative & Oncologic Pathophysiology. Faculty of Medicine and Pharmacy, Hassan II University, Casablanca, 20250, Morocco
- Department of Neurology. Ibn Rochd University Hospital, Casablanca, 20360, Morocco
| | - Mohamed Daghi
- Research Laboratory of Nervous System Diseases, Neurosensory Disorders & Disability. Faculty of Medicine & Pharmacy, Hassan II University, Casablanca, 20250, Morocco
| | - Nadia Tahiri Jouti
- Laboratory of Cellular and Molecular Inflammatory, Degenerative & Oncologic Pathophysiology. Faculty of Medicine and Pharmacy, Hassan II University, Casablanca, 20250, Morocco
| | - Suzanne Lesage
- Sorbonne University, Institut du Cerveau-Paris Brain Institute, ICM, INSERM, CNRS, Assistance Publique-Hôpitaux de Paris, Paris, 75013, France
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Koros C, Bougea A, Simitsi AM, Papagiannakis N, Angelopoulou E, Pachi I, Antonelou R, Bozi M, Stamelou M, Stefanis L. The Landscape of Monogenic Parkinson's Disease in Populations of Non-European Ancestry: A Narrative Review. Genes (Basel) 2023; 14:2097. [PMID: 38003040 PMCID: PMC10671808 DOI: 10.3390/genes14112097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/06/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
INTRODUCTION There has been a bias in the existing literature on Parkinson's disease (PD) genetics as most studies involved patients of European ancestry, mostly in Europe and North America. Our target was to review published research data on the genetic profile of PD patients of non-European or mixed ancestry. METHODS We reviewed articles published during the 2000-2023 period, focusing on the genetic status of PD patients of non-European origin (Indian, East and Central Asian, Latin American, sub-Saharan African and Pacific islands). RESULTS There were substantial differences regarding monogenic PD forms between patients of European and non-European ancestry. The G2019S Leucine Rich Repeat Kinase 2 (LRRK2) mutation was rather scarce in non-European populations. In contrast, East Asian patients carried different mutations like p.I2020T, which is common in Japan. Parkin (PRKN) variants had a global distribution, being common in early-onset PD in Indians, in East Asians, and in early-onset Mexicans. Furthermore, they were occasionally present in Black African PD patients. PTEN-induced kinase 1 (PINK1) and PD protein 7 (DJ-1) variants were described in Indian, East Asian and Pacific Islands populations. Glucocerebrosidase gene variants (GBA1), which represent an important predisposing factor for PD, were found in East and Southeast Asian and Indian populations. Different GBA1 variants have been reported in Black African populations and Latin Americans. CONCLUSIONS Existing data reveal a pronounced heterogeneity in the genetic background of PD. A number of common variants in populations of European ancestry appeared to be absent or scarce in patients of diverse ethnic backgrounds. Large-scale studies that include genetic screening in African, Asian or Latin American populations are underway. The outcomes of such efforts will facilitate further clinical studies and will possibly contribute to the identification of either new pathogenic mutations in already described genes or novel PD-related genes.
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Affiliation(s)
- Christos Koros
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
| | - Anastasia Bougea
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
| | - Athina Maria Simitsi
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
| | - Nikolaos Papagiannakis
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
| | - Efthalia Angelopoulou
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
| | - Ioanna Pachi
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
| | - Roubina Antonelou
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
| | - Maria Bozi
- Dafni Psychiatric Hospital, 12462 Athens, Greece;
- 2nd Department of Neurology, Attikon Hospital, National and Kapodistrian University of Athens, 12462 Athens, Greece
| | | | - Leonidas Stefanis
- 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece; (C.K.); (A.M.S.); (N.P.); (E.A.); (I.P.); (R.A.); (L.S.)
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Cuttler K, de Swardt D, Engelbrecht L, Kriel J, Cloete R, Bardien S. Neurexin 2 p.G849D variant, implicated in Parkinson's disease, increases reactive oxygen species, and reduces cell viability and mitochondrial membrane potential in SH-SY5Y cells. J Neural Transm (Vienna) 2022; 129:1435-1446. [PMID: 36242655 DOI: 10.1007/s00702-022-02548-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 10/10/2022] [Indexed: 01/20/2023]
Abstract
Parkinson's disease (PD) is a neurodegenerative movement disorder, affecting 1-2% of the human population over 65. A previous study by our group identified a p.G849D variant in neurexin 2α (NRXN2) co-segregating with PD, prompting validation of its role using experimental methods. This novel variant had been found in a South African family with autosomal dominant PD. NRXN2α is an essential synaptic maintenance protein with multiple functional roles at the synaptic cleft. The aim of the present study was to investigate the potential role of the translated protein NRXN2α and the observed mutant in PD by performing functional studies in an in vitro model. Wild-type and mutant NRXN2α plasmids were transfected into SH-SY5Y cells to assess the effect of the mutant on cell viability and apoptosis [(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) Assay; ApoTox-Glo™ Triplex Assay)], mitochondrial membrane potential (MMP; MitoProbe™ JC-1 Assay), mitochondrial network analysis (MitoTracker®) and reactive oxygen species (ROS; ROS-Glo™ H2O2 Assay). Cells transfected with the mutant NRXN2α plasmid showed decreased cell viability and MMP. They also exhibited increased ROS production. However, these cells showed no changes in mitochondrial fragmentation. Our findings led us to speculate that the p.G849D variant may be involved in a toxic feedback loop leading to neuronal death in PD. Mitochondrial dysfunction and synaptic dysfunction have been linked to PD. Therefore, findings from this exploratory study are in line with previous studies connecting these two processes and warrants further investigation into the role of this variant in other cellular and animal models.
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Affiliation(s)
- Katelyn Cuttler
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Dalene de Swardt
- Central Analytical Facilities, Stellenbosch University, Cape Town, South Africa
| | - Lize Engelbrecht
- Central Analytical Facilities, Stellenbosch University, Cape Town, South Africa
| | - Jurgen Kriel
- Central Analytical Facilities, Stellenbosch University, Cape Town, South Africa
| | - Ruben Cloete
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute, University of the Western Cape, Cape Town, South Africa
| | - Soraya Bardien
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
- South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Cape Town, South Africa.
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Low Levels of LRRK2 Gene Expression are Associated with LRRK2 SNPs and Contribute to Parkinson's Disease Progression. Neuromolecular Med 2020; 23:292-304. [PMID: 33015738 DOI: 10.1007/s12017-020-08619-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 09/26/2020] [Indexed: 10/23/2022]
Abstract
Parkinson's disease (PD) is a chronic neurodegenerative disease that has relatively slow progression with motor symptoms. Leucine-rich repeat kinase 2 (LRRK2) gene mutations and polymorphisms are suggested to be associated with PD. In this study, we aimed to investigate the association between single-nucleotide polymorphisms (SNPs) of the LRRK2 gene, namely, rs11176013, rs10878371, rs11835105, and PD. Genotypes of 132 PD cases and 133 healthy individuals were determined by qRT-PCR. Haplotype analysis was performed. Additionally, LRRK2 mRNA expression levels were determined in 83 PD cases and 55 healthy subjects. The relationship between LRRK2 mRNA levels, the target SNPs, and clinical data was also investigated. Our results indicated that the "GG" genotype and "G" allele of rs11176013 and the "CC" genotype and "C" allele of rs10878371 were more frequent in cases. The "GCG" haplotype was significantly more frequent in cases. LRRK2 mRNA expression levels in patients were significantly lower than those in healthy individuals. The patients with the "CC" genotype for rs10878371 and the "GG" genotype for rs11176013 had decreased LRRK2 mRNA levels. We found that the rs11176013 "GG" genotype and the rs10878371 "CC" genotype were less frequently seen in cases with akinetic rigid or combined akinetic rigid and tremor-dominant initial symptoms. Consequently, our results demonstrate that the rs11176013 and rs10878371 polymorphisms are associated with PD in a Turkish cohort, and moreover, these results suggest that these polymorphisms may affect the expression of the LRRK2 gene and disease progression and thus play a role in the pathogenesis of PD.
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5
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Rizig M, Ojo OO, Athanasiou-Fragkouli A, Agabi OP, Oshinaike OO, Houlden H, Okubadejo NU. Negative screening for 12 rare LRRK2 pathogenic variants in a cohort of Nigerians with Parkinson's disease. Neurobiol Aging 2020; 99:101.e15-101.e19. [PMID: 33158606 DOI: 10.1016/j.neurobiolaging.2020.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/04/2020] [Accepted: 09/28/2020] [Indexed: 01/27/2023]
Abstract
Leucine-rich repeat kinase 2 (LRRK2) gene mutations are the most common genetic cause of Parkinson's disease (PD). More than 300 rare LRRK2 variants have been described, with approximately 17 having confirmed or probable pathogenic role in PD. The distribution differs across ethnic groups, but no PD-related LRRK2 pathogenic variant has been described in persons of Black African ancestry within or outside Africa. We previously reported the absence of LRRK2 p.Gly2019Ser mutation in 126 PD and 55 controls from Nigeria. Using Kompetitive Allele Specific Polymerase Chain Reaction, we screened a new cohort of 92 Nigerians with PD and 210 ethnically matched controls for 12 rare LRRK2 variants shown to be pathogenic in other ethnic populations, including p.Gly2019Ser, p.Arg1441His, p.Gly2385Arg, p.Ala419Val, p.Arg1628Pro, p.Pro755Leu, p.Ile2020Thr, and Tyr1699Cys. All were absent in PD and controls, endorsing our previous findings and confirming that rare LRRK2 pathogenic variants reported in Caucasians, Asians, and persons of mixed ancestry are absent in West Africans. Future studies applying next generation sequencing are necessary to explore novel LRRK2 variants indigenous to Black Africans.
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Affiliation(s)
- Mie Rizig
- Department of Molecular Neuroscience, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
| | - Oluwadamilola O Ojo
- Department of Medicine, College of Medicine of the University of Lagos, Lagos, Nigeria; Neurology Unit, Department of Medicine, Lagos University Teaching Hospital, Idi-Araba, Lagos State, Nigeria
| | - Alkyoni Athanasiou-Fragkouli
- Department of Molecular Neuroscience, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
| | - Osigwe P Agabi
- Neurology Unit, Department of Medicine, Lagos University Teaching Hospital, Idi-Araba, Lagos State, Nigeria
| | - Olajumoke O Oshinaike
- Department of Medicine, Lagos State University College of Medicine and Lagos State University Teaching Hospital, Ikeja, Nigeria
| | - Henry Houlden
- Department of Molecular Neuroscience, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
| | - Njideka U Okubadejo
- Department of Medicine, College of Medicine of the University of Lagos, Lagos, Nigeria; Neurology Unit, Department of Medicine, Lagos University Teaching Hospital, Idi-Araba, Lagos State, Nigeria.
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Padmanabhan S, Fiske BK, Baptista MA. The Michael J. Fox Foundation's Strategies for Accelerating Translation of LRRK2 into Therapies for Parkinson Disease. Cells 2020; 9:E1878. [PMID: 32796584 PMCID: PMC7466022 DOI: 10.3390/cells9081878] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/01/2020] [Accepted: 08/07/2020] [Indexed: 12/16/2022] Open
Abstract
Since 2005, The Michael J. Fox Foundation for Parkinson's Research (MJFF) has invested significant funding and non-funding effort to accelerate research and drug development activity around the Parkinson disease (PD)-associated protein LRRK2. MJFF has spearheaded multiple public/private pre-competitive collaborations that have contributed to our understanding of LRRK2 function; de-risked potential safety questions around the therapeutic use of LRRK2 kinase inhibitors; and generated critical research tools, biosamples, and data for the field. Several LRRK2-targeted therapies are now in human testing due to the hard work of so many in the PD community. In this perspective, we present a holistic description and model of how our Foundation's support targeted important barriers to LRRK2 research and helped move the field into clinical trials.
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Affiliation(s)
- Shalini Padmanabhan
- The Michael J. Fox Foundation for Parkinson’s Research, Grand Central Station, P.O. Box 4777, New York, NY 10120, USA
| | | | - Marco A.S. Baptista
- The Michael J. Fox Foundation for Parkinson’s Research, Grand Central Station, P.O. Box 4777, New York, NY 10120, USA
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Dekker MCJ, Coulibaly T, Bardien S, Ross OA, Carr J, Komolafe M. Parkinson's Disease Research on the African Continent: Obstacles and Opportunities. Front Neurol 2020; 11:512. [PMID: 32636796 PMCID: PMC7317302 DOI: 10.3389/fneur.2020.00512] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 05/08/2020] [Indexed: 12/11/2022] Open
Abstract
The burden of Parkinson's disease (PD) is becoming increasingly important in the context of an aging African population. Although PD has been extensively investigated with respect to its environmental and genetic etiology in various populations across the globe, studies on the African continent remain limited. In this Perspective article, we review some of the obstacles that are limiting research and creating barriers for future studies. We summarize what research is being done in four sub-Saharan countries and what the key elements are that are needed to take research to the next level. We note that there is large variation in neurological and genetic research capacity across the continent, and many opportunities for unexplored areas in African PD research. Only a handful of countries possess appropriate infrastructure and personnel, whereas the majority have yet to develop such capacity. Resource-constrained environments strongly determines the possibilities of performing research locally, and unidirectional export of biological samples and genetic data remains a concern. Local-regional partnerships, in collaboration with global PD consortia, should form an ethically appropriate solution, which will lead to a reduction in inequality and promote capacity building on the African continent.
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Affiliation(s)
- Marieke C J Dekker
- Department of Medicine and Pediatrics, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Toumany Coulibaly
- Service de Neurologie, Centre Hospitalier Universitaire du Point "G", Bamako, Mali
| | - Soraya Bardien
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Owen A Ross
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, United States.,Department of Clinical Genomics, Mayo Clinic, Jacksonville, FL, United States
| | - Jonathan Carr
- Division of Neurology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Morenikeji Komolafe
- Department of Medicine, College of Health Sciences, Obafemi Awolowo University, Ile-Ife, Nigeria
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8
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Frequency of the LRRK2 G2019S mutation in South African patients with Parkinson’s disease. Neurogenetics 2019; 20:215-218. [DOI: 10.1007/s10048-019-00588-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 08/27/2019] [Indexed: 12/14/2022]
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Leucine rich repeat kinase 2 (LRRK2) GLY2019SER mutation is absent in a second cohort of Nigerian Africans with Parkinson disease. PLoS One 2018; 13:e0207984. [PMID: 30507963 PMCID: PMC6277104 DOI: 10.1371/journal.pone.0207984] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 11/08/2018] [Indexed: 01/05/2023] Open
Abstract
To date the LRRK2 p.G2019S mutation remains the most common genetic cause of Parkinson disease (PD) worldwide. It accounts for up to 6% of familial and approximately 1.5% of sporadic cases. LRRK2 has a kinase enzymatic domain which provides an attractive potential target for drug therapies and LRRK2 kinase inhibitors are in development. Prevalence of the p.G2019S has a variable ethnic and geographic distribution, the highest reported among Ashkenazi Jews (30% in patients with familial PD, 14% in sporadic PD, 2.0% in controls) and North African Berbers (37% in patients with familial PD, 41% in sporadic PD, and 1% in controls). Little is known about the frequency of the LRRK2 p.G2019S among populations in sub-Saharan Africa. Our group and others previously reported that the p.G2019S is absent in a small cohort of Nigerian PD patients and controls. Here we used Kompetitive Allele Specific PCR (KASP) assay to screen for the p.G2019S in a larger cohort of Black African PD patients (n = 126) and healthy controls (n = 54) from Nigeria. Our analysis confirmed that all patients and controls are negative for the p.G2019S mutation. This report provides further evidence that the LRRK2 p.G2019S is not implicated in PD in black populations from Nigeria and support the notion that p.G2019S mutation originated after the early human dispersal from sub-Saharan Africa. Further studies using larger cohorts and advance sequencing technology are required to underpin the genetic causes of PD in this region.
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Williams U, Bandmann O, Walker R. Parkinson's Disease in Sub-Saharan Africa: A Review of Epidemiology, Genetics and Access to Care. J Mov Disord 2018; 11:53-64. [PMID: 29860783 PMCID: PMC5990907 DOI: 10.14802/jmd.17028] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 10/02/2017] [Accepted: 12/11/2017] [Indexed: 12/20/2022] Open
Abstract
A low prevalence of Parkinson's disease (PD) has been reported in the Sub-Saharan Africa (SSA) region. The genetic causes and clinical features of PD in this region have been poorly described. Very few reports have examined the availability and access to evidence-based quality care for people living with PD in this region. We reviewed all publications focusing on idiopathic PD from SSA published up to May 2016 and observed a prevalence of PD ranging from 7/100,000 in Ethiopia to 67/100,000 in Nigeria. The most recent community-based study reported a mean age at onset of 69.4 years. The infrequent occurrence of mutations in established PD genes was also observed in the region. Treatments were non-existent or at best irregular. Additionally, there is a lack of well-trained medical personnel and multidisciplinary teams in most countries in this region. Drugs for treating PD are either not available or unaffordable. Large-scale genetic and epidemiological studies are therefore needed in SSA to provide further insights into the roles of genetics and other etiological factors in the pathogenesis of PD. The quality of care also requires urgent improvement to meet the basic level of care required by PD patients.
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Affiliation(s)
- Uduak Williams
- Neurology Unit, Internal Medicine Department, University of Calabar Teaching Hospital, Calabar, Nigeria
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Oliver Bandmann
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Richard Walker
- Department of Elderly Medicine, North Tyneside General Hospital, Newcastle, UK
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Age-Dependent Dopaminergic Neurodegeneration and Impairment of the Autophagy-Lysosomal Pathway in LRRK-Deficient Mice. Neuron 2017; 96:796-807.e6. [PMID: 29056298 DOI: 10.1016/j.neuron.2017.09.036] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 09/14/2017] [Accepted: 09/22/2017] [Indexed: 12/21/2022]
Abstract
LRRK2 mutations are the most common genetic cause of Parkinson's disease, but LRRK2's normal physiological role in the brain is unclear. Here, we show that inactivation of LRRK2 and its functional homolog LRRK1 results in earlier mortality and age-dependent, selective neurodegeneration. Loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) and of noradrenergic neurons in the locus coeruleus is accompanied with increases in apoptosis, whereas the cerebral cortex and cerebellum are unaffected. Furthermore, selective age-dependent neurodegeneration is only present in LRRK-/-, not LRRK1-/- or LRRK2-/- brains, and it is accompanied by increases in α-synuclein and impairment of the autophagy-lysosomal pathway. Quantitative electron microscopy (EM) analysis revealed age-dependent increases of autophagic vacuoles in the SNpc of LRRK-/- mice before the onset of DA neuron loss. These findings revealed an essential role of LRRK in the survival of DA neurons and in the regulation of the autophagy-lysosomal pathway in the aging brain.
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Bouhouche A, Tibar H, Ben El Haj R, El Bayad K, Razine R, Tazrout S, Skalli A, Bouslam N, Elouardi L, Benomar A, Yahyaoui M, Regragui W. LRRK2 G2019S Mutation: Prevalence and Clinical Features in Moroccans with Parkinson's Disease. PARKINSON'S DISEASE 2017; 2017:2412486. [PMID: 28465860 PMCID: PMC5390546 DOI: 10.1155/2017/2412486] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 03/23/2017] [Indexed: 02/07/2023]
Abstract
Background. The LRRK2 G2019S mutation is the most common genetic determinant of Parkinson's disease (PD) identified to date. This mutation, reported in both familial and sporadic PD, occurs at elevated frequencies in Maghreb population. In the present study, we examined the prevalence of the G2019S mutation in the Moroccan population and we compared the motor and nonmotor phenotype of G2019S carriers to patients with idiopathic Parkinson's disease. Methods. 100 PD patients were assessed for motor and nonmotor symptoms, current medication, and motor complication including motor fluctuations and dyskinesia. The LRRK2 G2019S mutation was investigated by direct sequencing in patients and ethnically matched controls, all of Moroccan origin. Results. Among the 100 PD Moroccan patients, 41 (41%) were carriers of the G2019S mutation. The mutation frequency was higher among probands with autosomal dominant inheritance (76%) than among sporadic ones (28%). Interestingly, G2019S mutation was also found in 5% of control individuals. Clinically, patients carrying the G2019S mutation have more dystonia (OR = 4.6, p = 0.042) and more sleep disorders (OR = 2.4, p = 0.045) than noncarriers. Conclusions. The LRRK2 G2019S prevalence in Morocco is the highest in the world reported to date. Some clinical features in G2019S carriers such as dystonia and sleep disturbances are worth noting.
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Affiliation(s)
- Ahmed Bouhouche
- Research Team in Neurology and Neurogenetics, Medical School and Pharmacy, Mohammed V University, Rabat, Morocco
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Houyam Tibar
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Rafiqua Ben El Haj
- Research Team in Neurology and Neurogenetics, Medical School and Pharmacy, Mohammed V University, Rabat, Morocco
| | - Khalil El Bayad
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Rachid Razine
- Laboratory of Public Health, Medical School and Pharmacy, Mohammed V University, Rabat, Morocco
| | - Sanaa Tazrout
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Asmae Skalli
- Research Team in Neurology and Neurogenetics, Medical School and Pharmacy, Mohammed V University, Rabat, Morocco
| | - Naima Bouslam
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Loubna Elouardi
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Ali Benomar
- Research Team in Neurology and Neurogenetics, Medical School and Pharmacy, Mohammed V University, Rabat, Morocco
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Mohammed Yahyaoui
- Research Team in Neurology and Neurogenetics, Medical School and Pharmacy, Mohammed V University, Rabat, Morocco
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
| | - Wafa Regragui
- Research Team in Neurology and Neurogenetics, Medical School and Pharmacy, Mohammed V University, Rabat, Morocco
- Department of Neurology and Neurogenetics, Specialties Hospital, Rabat, Morocco
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Barkhuizen M, Anderson DG, van der Westhuizen FH, Grobler AF. A molecular analysis of the GBA gene in Caucasian South Africans with Parkinson's disease. Mol Genet Genomic Med 2017; 5:147-156. [PMID: 28361101 PMCID: PMC5370228 DOI: 10.1002/mgg3.267] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 11/16/2016] [Accepted: 11/22/2016] [Indexed: 01/07/2023] Open
Abstract
Background The molecular basis of Parkinson's disease in South African population groups remains elusive. To date, substitutions in the GBA gene are the most common large‐effect genetic risk factor for Parkinson's disease. The primary objective of this study was to determine the prevalence of GBA substitutions in South Africans with idiopathic Parkinson's disease. Methods Participants were recruited from tertiary hospitals in the Gauteng Province in South Africa. All participants were screened for substitutions in GBA exon 8‐11 and the full coding region was analysed in 20 participants. Peripheral β‐glucocerebrosidase enzymatic activity of GBA‐carriers was measured in mixed leukocytes. Results Of 105 Caucasian Parkinson's disease participants (82.7% Afrikaner) with an average age of disease onset of 61.9 ± 12.2 years and 40 controls (age 73.4 ± 12.4 years) were included. Heterozygous GBA substitutions were identified in 12.38% of affected participants (p.G35A, p.E326K, p.I368T, p.T369M, p.N370S, p.P387L and p.K441N) and 5.00% of controls (p.E326K and p.T369M). The substitutions ranged from predicted benign to moderately damaging; with p.E326K and p.T369M most prevalent, followed by the Afrikaner Gaucher disease substitution p.P387L. Severe Gaucher disease mutations, like p.L444P, were absent in this cohort. Enzyme activity analysis revealed a nonsignificant reduction in the GBA‐Parkinson's disease individuals (14.49 ± 2.30 nmol/h/mg protein vs. 15.98 ± 3.06 nmol/h/mg in control samples). GBA substitutions occur in both young‐onset and late‐onset Parkinson's cases in the cohort. Conclusion Mild GBA substitutions that may not cause Gaucher disease were a common risk factor for Parkinson's disease in the participant group.
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Affiliation(s)
- Melinda Barkhuizen
- DST/NWU Preclinical Drug Development PlatformNorth-West UniversityPotchefstroom2520South Africa; Department of PaediatricsSchool for Mental Health and NeuroscienceMaastricht UniversityMaastricht6229The Netherlands
| | - David G Anderson
- Department of Neurology University of the Witwatersrand Donald Gordon Medical Centre Johannesburg 2193 South Africa
| | | | - Anne F Grobler
- DST/NWU Preclinical Drug Development Platform North-West University Potchefstroom 2520 South Africa
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14
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Monfrini E, Di Fonzo A. Leucine-Rich Repeat Kinase (LRRK2) Genetics and Parkinson's Disease. ADVANCES IN NEUROBIOLOGY 2017; 14:3-30. [PMID: 28353276 DOI: 10.1007/978-3-319-49969-7_1] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The discovery of LRRK2 mutations as a cause of Parkinson's disease (PD), including the sporadic late-onset form, established the decisive role of genetics in the field of PD research. Among LRRK2 mutations, the G2019S, mostly lying in a haplotype originating from a common Middle Eastern ancestor, has been identified in different populations worldwide. The G2385R and R1628P variants represent validated risk factors for PD in Asian populations. Here, we describe in detail the origin, the present worldwide epidemiology, and the penetrance of LRRK2 mutations. Furthermore, this chapter aims to characterize other definitely/probably pathogenic mutations and risk variants of LRRK2. Finally, we provide some general guidelines for a LRRK2 genetic testing and counseling. In summary, LRRK2 discovery revolutionized the understanding of PD etiology and laid the foundation for a promising future of genetics in PD research.
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Affiliation(s)
- Edoardo Monfrini
- IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Dino Ferrari Center, Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Alessio Di Fonzo
- IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Dino Ferrari Center, Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.
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15
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Kasten M, Marras C, Klein C. Nonmotor Signs in Genetic Forms of Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 133:129-178. [DOI: 10.1016/bs.irn.2017.05.030] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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16
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Akinyemi RO, Owolabi MO, Oyeniyi T, Ovbiagele B, Arnett DK, Tiwari HK, Walker R, Ogunniyi A, Kalaria RN. Neurogenomics in Africa: Perspectives, progress, possibilities and priorities. J Neurol Sci 2016; 366:213-223. [PMID: 27288810 DOI: 10.1016/j.jns.2016.05.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 05/04/2016] [Indexed: 11/18/2022]
Abstract
The understanding of the genetic basis of neurological disorders has grown rapidly in the last two decades. Despite the genomic heterogeneity within African populations, large-scale candidate gene or linkage and exome studies are lacking. However, current knowledge on neurogenetics in African populations is limited and geographically very uneven. Isolated reports indicate the existence of autosomal dominant or recessive conditions incorporating cerebrovascular, movement, neuromuscular, seizure and motor neuron disorders in Africans. In addition, few African families with neurodegenerative disorders associated with dementia have been characterized in North, West and South Africa. The current insurgency in genomic research triggered by among others the Human Health and Heredity (H3) Africa Initiative indicates that there are unique opportunities to advance our knowledge and understanding of the influence of genomic variation on the pattern, presentations and prognosis of neurological disorders in Africa. These have enormous potential to unmask novel genes and molecular pathways germane to the neurobiology of brain disorders. It would facilitate the development of novel diagnostics, preventative and targeted treatments in the new paradigm of precision medicine. Nevertheless, it is crucial to strike a balance between effective traditional public health strategies and personalized genome based care. The translational barriers can be overcome through robust stakeholder engagement and sustainable multilevel, multigenerational and multidisciplinary capacity building and infrastructural development for genomic medicine in Africa.
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Affiliation(s)
- Rufus O Akinyemi
- Institute for Advanced Medical Research and Training, College of Medicine, University of Ibadan, Nigeria; Institute of Neuroscience, Newcastle University, UK.
| | - Mayowa O Owolabi
- Department of Medicine, College of Medicine, University of Ibadan, Nigeria
| | | | - Bruce Ovbiagele
- Department of Neurosciences, Medical University of South Carolina, USA
| | - Donna K Arnett
- School of Public Health, University of Alabama at Birmingham, USA
| | - Hemant K Tiwari
- School of Public Health, University of Alabama at Birmingham, USA
| | - Richard Walker
- Institute of Health and Society, Newcastle University, UK
| | - Adesola Ogunniyi
- Department of Medicine, College of Medicine, University of Ibadan, Nigeria
| | - Raj N Kalaria
- Institute of Neuroscience, Newcastle University, UK.
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17
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Quansah E, Karikari TK. Neuroscience-related research in Ghana: a systematic evaluation of direction and capacity. Metab Brain Dis 2016; 31:11-24. [PMID: 26344503 PMCID: PMC4718959 DOI: 10.1007/s11011-015-9724-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 08/24/2015] [Indexed: 12/01/2022]
Abstract
Neurological and neuropsychiatric diseases account for considerable healthcare, economic and social burdens in Ghana. In order to effectively address these burdens, appropriately-trained scientists who conduct high-impact neuroscience research will be needed. Additionally, research directions should be aligned with national research priorities. However, to provide information about current neuroscience research productivity and direction, the existing capacity and focus need to be identified. This would allow opportunities for collaborative research and training to be properly explored and developmental interventions to be better targeted. In this study, we sought to evaluate the existing capacity and direction of neuroscience-related research in Ghana. To do this, we examined publications reporting research investigations authored by scientists affiliated with Ghanaian institutions in specific areas of neuroscience over the last two decades (1995-2015). 127 articles that met our inclusion criteria were systematically evaluated in terms of research foci, annual publication trends and author affiliations. The most actively-researched areas identified include neurocognitive impairments in non-nervous system disorders, depression and suicide, epilepsy and seizures, neurological impact of substance misuse, and neurological disorders. These studies were mostly hospital and community-based surveys. About 60% of these articles were published in the last seven years, suggesting a recent increase in research productivity. However, data on experimental and clinical research outcomes were particularly lacking. We suggest that future investigations should focus on the following specific areas where information was lacking: large-scale disease epidemiology, effectiveness of diagnostic platforms and therapeutic treatments, and the genetic, genomic and molecular bases of diseases.
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Affiliation(s)
- Emmanuel Quansah
- Pharmacology, Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH, UK.
- Department of Molecular Biology and Biotechnology, School of Biological Science, University of Cape Coast, Cape Coast, Ghana.
| | - Thomas K Karikari
- Neuroscience, School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.
- Midlands Integrative Biosciences Training Partnership, University of Warwick, Coventry, CV4 7AL, UK.
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18
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Blanckenberg J, Bardien S, Glanzmann B, Okubadejo NU, Carr JA. The prevalence and genetics of Parkinson's disease in sub-Saharan Africans. J Neurol Sci 2013; 335:22-5. [PMID: 24079843 DOI: 10.1016/j.jns.2013.09.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Revised: 08/08/2013] [Accepted: 09/06/2013] [Indexed: 01/12/2023]
Abstract
Parkinson's disease (PD) is under-studied in Black Sub-Saharan African (SSA) populations. To date, there have been only six prevalence and no incidence studies. The crude prevalence of PD in SSA varies from 7 to 20 per 100,000, which is appreciably lower than in Caucasian populations. There are a limited number of published studies (nine) on the genetic factors associated with PD in SSA populations. Mutations have been reported in the parkin gene, and are restricted to only three patients (two Black South Africans and one Zambian). No mutations have been identified in the LRRK2, SNCA, PINK, or DJ-1 genes. Given the unique ancestry of SSA populations, their inclusion in genetic studies may provide a substantial contribution to the identification of novel genetic factors and genetic-environmental interactions underlying this disorder. More initiatives are needed to drive further research on PD in these populations and to facilitate collaborative projects across Africa.
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Affiliation(s)
- Janine Blanckenberg
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, University of Stellenbosch, Cape Town, South Africa
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19
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Liu M, Bender SA, Cuny GD, Sherman W, Glicksman M, Ray SS. Type II kinase inhibitors show an unexpected inhibition mode against Parkinson's disease-linked LRRK2 mutant G2019S. Biochemistry 2013; 52:1725-36. [PMID: 23379419 PMCID: PMC3966205 DOI: 10.1021/bi3012077] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A number of well-known type II inhibitors (ATP-noncompetitive) that bind kinases in their DFG-out conformation were tested against wild-type LRRK2 and the most common Parkinson's disease-linked mutation, G2019S. We found that traditional type II inhibitors exhibit surprising variability in their inhibition mechanism between the wild type (WT) and the G2019S mutant of LRRK2. The type II kinase inhibitors were found to work in an ATP-competitive fashion against the G2019S mutant, whereas they appear to follow the expected noncompetitive mechanism against WT. Because the G2019S mutation lies in the DXG motif (DYG in LRRK2 but DFG in most other kinases) of the activation loop, we explored the structural consequence of the mutation on loop dynamics using an enhanced sampling method called metadynamics. The simulations suggest that the G2019S mutation stabilizes the DYG-in state of LRRK2 through a series of hydrogen bonds, leading to an increase in the conformational barrier between the active and inactive forms of the enzyme and a relative stabilization of the active form. The conformational bias toward the active form of LRRK2 mutants has two primary consequences. (1) The mutant enzyme becomes hyperactive, a known contributor to the Parkinsonian phenotype, as a consequence of being "locked" into the activated state, and (2) the mutation creates an unusual allosteric pocket that can bind type II inhibitors but in an ATP-competitive fashion. Our results suggest that developing type II inhibitors, which are generally considered superior to type I inhibitors because of desirable selectivity profiles, might be especially challenging for the G2019S LRRK2 mutant.
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Affiliation(s)
- Min Liu
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
| | | | - Gregory D Cuny
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
| | - Woody Sherman
- Schrodinger, 120 W. 45 Street, New York, NY, 10036
- Proteus Discovery Inc. 411 Massachusetts avenue, Cambridge, MA 02139-410
| | - Marcie Glicksman
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
| | - Soumya S. Ray
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
- Department of Neurology, Brigham and Women’s Hospital
- Center for Neurologic Diseases, Brigham and Women’s Hospital
- Proteus Discovery Inc. 411 Massachusetts avenue, Cambridge, MA 02139-410
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20
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Yonova-Doing E, Atadzhanov M, Quadri M, Kelly P, Shawa N, Musonda STS, Simons EJ, Breedveld GJ, Oostra BA, Bonifati V. Analysis of LRRK2, SNCA, Parkin, PINK1, and DJ-1 in Zambian patients with Parkinson's disease. Parkinsonism Relat Disord 2012; 18:567-71. [PMID: 22445250 DOI: 10.1016/j.parkreldis.2012.02.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 01/25/2012] [Accepted: 02/29/2012] [Indexed: 12/26/2022]
Abstract
Recent studies delineate substantial genetic components in Parkinson's disease (PD). However, very few studies were performed in Sub-Saharan African populations. Here, we explore the contribution of known PD-causing genes in patients of indigenous Zambian ancestry. We studied thirty-nine Zambian patients, thirty-eight with PD and one with parkinsonian-pyramidal syndrome (18% familial; average onset age 54.9 ± 12.2 years). In the whole group, all SNCA exons and LRRK2 exons 29 to 48 (encoding for important functional domains) were sequenced. In the familial patients and those with onset <55 years (n = 22) the whole LRRK2 coding region was sequenced (51 exons). In the patients with onset <50 years (n = 12), all parkin, PINK1, and DJ-1 exons were sequenced, and dosage analysis of parkin, PINK1, DJ-1, LRRK2, and SNCA was performed. Dosage analysis was also performed in the majority of the late-onset patients. The LRRK2 p.Gly2019Ser mutation was not detected. A novel LRRK2 missense variant (p.Ala1464Gly) of possible pathogenic role was found in one case. Two heterozygous, likely disease-causing deletions of parkin (exon 2 and exon 4) were detected in an early-onset case. Pathogenic mutations were not detected in SNCA, PINK1, or DJ-1. We also report variability at several single nucleotide polymorphisms in the above-mentioned genes. This is the first molecular genetic study in Zambian PD patients, and the first comprehensive analysis of the LRRK2 and SNCA genes in a Sub-Saharan population. Common disease-causing mutations were not detected, suggesting that further investigations in PD patients from these populations might unravel the role of additional, still unknown genes.
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Affiliation(s)
- Ekaterina Yonova-Doing
- Department of Clinical Genetics, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands
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21
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Bardien S, Lesage S, Brice A, Carr J. Genetic characteristics of leucine-rich repeat kinase 2 (LRRK2) associated Parkinson's disease. Parkinsonism Relat Disord 2011; 17:501-8. [PMID: 21641266 DOI: 10.1016/j.parkreldis.2010.11.008] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 11/09/2010] [Accepted: 11/09/2010] [Indexed: 11/30/2022]
Abstract
Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the progressive and selective degeneration of nigrostriatal dopaminergic neurons. The discovery of at least six PD-causing genes in predominantly early-onset forms of the disorder has cemented a genetic component to the etiology. Notably, the discovery of mutations in the LRRK2 gene in patients presenting with typical 'sporadic' PD with ages at onset in their sixties and seventies has shifted paradigms in the field of PD research. The G2019S mutation in LRRK2 has been found in diverse populations worldwide and usually resides on a common haplotype revealing that many of these individuals share a common ancestor, probably of Middle Eastern origin. The only validated coding susceptibility alleles for PD, G2385R and R1628P, are both in this gene but to date have been found exclusively in Asian populations. Concomitant with genetic testing for PD is the need for appropriate and informed genetic counseling. Families of patients with LRRK2 mutations and susceptibility alleles need to be informed about the current lack of disease preventative strategies and the implications surrounding incomplete penetrance. In summary, single-handedly LRRK2 has had a major impact on the field of PD research and the findings have been of interest to both clinicians and scientists. We anticipate that other genes of such major impact exist for PD and look forward to their discovery.
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Affiliation(s)
- Soraya Bardien
- Division of Molecular Biology and Human Genetics, Stellenbosch University, Cape Town, South Africa
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22
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Cilia R, Sironi F, Akpalu A, Cham M, Sarfo FS, Brambilla T, Bonetti A, Amboni M, Goldwurm S, Pezzoli G. Screening LRRK2 gene mutations in patients with Parkinson's disease in Ghana. J Neurol 2011; 259:569-70. [PMID: 21842440 DOI: 10.1007/s00415-011-6210-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/29/2011] [Accepted: 08/01/2011] [Indexed: 10/17/2022]
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23
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Cilia R, Akpalu A, Cham M, Bonetti A, Amboni M, Faceli E, Pezzoli G. Parkinson’s disease in sub-Saharan Africa: step-by-step into the challenge. Neurodegener Dis Manag 2011. [DOI: 10.2217/nmt.11.28] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SUMMARY Nowadays, most developing countries are experiencing a demographic transition characterized by an increase in mean life expectancy, thus the prevalence of age-related disorders such as Parkinson’s disease (PD) are expected to increase accordingly. Previous reports suggest that PD is still largely underdiagnosed and undertreated in low-income areas because of the limited availability of trained staff and medication, as well as inadequate patient follow-up and education. In this article, we performed a step-by-step assessment of the main challenges encountered in the management of patients with PD in developing countries, ranging from diagnostic to therapeutic issues. These issues stem from published literature and, mostly, from our direct experience of PD management in Ghana and Zambia through personal contribution of local physicians who face this challenge in their routine clinical practice.
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Affiliation(s)
| | | | | | - Alba Bonetti
- Parkinson Institute, Istituti Clinici di Perfezionamento, Milan, Italy
| | - Marianna Amboni
- Centro Malattie Neurodegenerative, Salerno, University of Salerno, Italy
- IDC Hermitage-Capodimonte, Naples, Italy
| | | | - Gianni Pezzoli
- Parkinson Institute, Istituti Clinici di Perfezionamento, Milan, Italy
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24
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Identification of Parkinson’s disease candidate genes using CAESAR and screening of MAPT and SNCAIP in South African Parkinson’s disease patients. J Neural Transm (Vienna) 2011; 118:889-97. [DOI: 10.1007/s00702-011-0591-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 01/24/2011] [Indexed: 01/08/2023]
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25
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Keyser RJ, Lesage S, Brice A, Carr J, Bardien S. Assessing the prevalence of PINK1 genetic variants in South African patients diagnosed with early- and late-onset Parkinson's disease. Biochem Biophys Res Commun 2010; 398:125-9. [PMID: 20558144 DOI: 10.1016/j.bbrc.2010.06.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 06/10/2010] [Indexed: 01/08/2023]
Abstract
Mutations in the PINK1 gene are the second most common cause after parkin of autosomal recessive early-onset Parkinson's disease (PD). PINK1 is a protein kinase that is localized to the mitochondrion and is ubiquitously expressed in the human brain. Recent studies aimed at elucidating the function of PINK1, have found that it has neuroprotective properties against mitochondrial dysfunction and proteasomally-induced apoptosis. In the present study, we aimed to investigate the prevalence of PINK1 genetic variants in 154 South African PD patients from all ethnic groups. Mutation screening was performed using the High-Resolution Melt technique and direct sequencing. A total of 16 sequence variants were identified: one known homozygous mutation (Y258X), two heterozygous missense variants (P305A and E476K), and 13 polymorphisms of which five were novel. No homozygous exonic deletions were detected. The novel P305A variant was found in a female patient of Black Xhosa ethnicity who has a positive family history of the disease and an age at onset of 30years. This variant has the potential to modulate enzymatic activity due to its location in the kinase domain. This is the first report on mutation screening of PINK1 in the South African population. Results from the present study showed that point mutations and homozygous exonic deletions in PINK1 are not a common cause of PD in the South African population.
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Affiliation(s)
- Rowena J Keyser
- Division of Molecular Biology and Human Genetics, Faculty of Health Sciences, University of Stellenbosch, Cape Town, South Africa
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