| 11. |
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| 12. |
- Rödström, E. Ygland, et al.
(författare)
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Genomic analyses of a large Swedish multi-incident kindred with autosomal dominant Parkinson’s disease with dementia
- 2023
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Ingår i: Parkinsonism & Related Disorders. - 1353-8020. ; 113:Supp, s. 28-29
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Konferensbidrag (refereegranskat)abstract
- Background:The known genetic causes for Parkinson’s disease (PD) onlyexplain a small proportion of the familial aggregation of PD. Despiteintensive efforts by researchers internationally, identifying and confirmingadditional monogenic causes for PD has been difficult.Methods:We examined 16 members of a large family with multi-incidentPD and dementia. Eight members were examined by whole exome (WES)or whole genome sequencing. Rare variants co-segregating with the disease were evaluated based on their distribution in additional familymembers and known gene functions. WES data from 843 PD cases and 885controls were screened for the two most highly ranked candidate variantsand used for gene burden analysis.Results:Clinically, all affected family members had typical PD withcognitive decline. Two affected individuals showed typical PD neuropathology. Out of nine genetic variants identified, we highlighted two as goodcandidates for causing this family’s PD. However, co-segregation with PDwas imperfect and this study was complicated by the fact that somegenotyped family members showed mild motor symptoms of uncertaincause, or cognitive decline without apparent motor dysfunction. Geneburden analysis showed no difference between cases and controls in thefrequency of potentially deleterious variants in the top-candidate genes.Nonetheless, factors that could indicate an impact of either of the two topcandidate genetic variants were found as one of the variants was identifiedin one additional familial PD proband from the case series and geneticvariants in the other top-candidate gene had previously been associatedwith an increased risk for PD in humans.Conclusions: Our study was not able to determine a single high-impactvariant as the cause of PD with cognitive decline in the family despitedetailed clinical and genetic assessments, but we nominate two potentialcandidate variants. Reduced penetrance and phenocopies may complicategenomic studies of families with PD.
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| 14. |
- Soto-Ortolaza, A. I., et al.
(författare)
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GWAS risk factors in Parkinson's disease : LRRK2 coding variation and genetic interaction with PARK16
- 2013
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Ingår i: American Journal of Neurodegenerative Disease. - 2165-591X. ; 2:4, s. 99-287
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Tidskriftsartikel (refereegranskat)abstract
- Parkinson's disease (PD) is a multifactorial movement disorder characterized by progressive neurodegeneration. Genome-wide association studies (GWAS) have nominated over fifteen distinct loci associated with risk of PD, however the biological mechanisms by which these loci influence disease risk are mostly unknown. GWAS are only the first step in the identification of disease genes: the specific causal variants responsible for the risk within the associated loci and the interactions between them must be identified to fully comprehend their impact on the development of PD. In the present study, we first attempted to replicate the association signals of 17 PD GWAS loci in our series of 1381 patients with PD and 1328 controls. BST1, SNCA, HLA-DRA, CCDC62/HIP1R and MAPT all showed a significant association with PD under different models of inheritance and LRRK2 showed a suggestive association. We then examined the role of coding LRRK2 variants in the GWAS association signal for that gene. The previously identified LRRK2 risk mutant p.M1646T and protective haplotype p.N551K-R1398H-K1423K did not explain the association signal of LRRK2 in our series. Finally, we investigated the gene-gene interaction between PARK16 and LRRK2 that has previously been proposed. We observed no interaction between PARK16 and LRRK2 GWAS variants, but did observe a non-significant trend toward interaction between PARK16 and LRRK2 variants within the protective haplotype. Identification of causal variants and the interactions between them is the crucial next step in making biological sense of the massive amount of data generated by GWAS studies. Future studies combining larger sample sizes will undoubtedly shed light on the complex molecular interplay leading to the development of PD.
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| 15. |
- Springer, W, et al.
(författare)
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Heterozygous PINK1 p.G411S mutation increases risk for Parkinson's disease (PD)
- 2016
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Ingår i: Movement Disorders. - : Wiley. - 0885-3185. ; 31:Suppl. S2, s. 282-282
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Konferensbidrag (refereegranskat)abstract
- Objective: To investigate the possible disease-association and pathogenic mechanisms of heterozygous PINK1 mutations from a genetic, functional, and structural perspective. Background: It has been postulated that heterozygous mutations in recessive PD genes may increase disease risk. In particular, the PINK1 p.G411S mutation has been reported in families with dominant inheritance patterns, suggesting that it might confer a sizeable disease risk. Methods: We performed a pedigree analysis of seven patients with a heterozygous PINK1 p.G411S mutation with at least one additional affected family member. We screened five case-control series and performed a meta-analysis of previous studies that had examined the variant. For functional cell-based analyses, we used patients skin fibroblast from PINK1 p.G411S or p.Q456X heterozygotes and investigated endogenous protein levels and kinase activity by biochemistry and imaging. For structural analyses, we performed molecular modeling and generated monomeric and dimeric forms of wild type (WT) and mutant PINK1 protein. Using molecular dynamics simulations, we analyzed effects of the p.G411S mutation on WT PINK1 in a heterodimeric complex over time. Results: Our analyses revealed a genetic association of heterozygous PINK1 p.G411S mutation with an increased risk for PD and a possible dominant inheritance with incomplete co-segregation. In patients skin fibroblasts, we establish a dominant negative mode for heterozygous p.G411S mutations under endogenous conditions. While total PINK1 protein levels were similar to controls upon mitochondrial stress, cellular PINK1 kinase activity was significantly reduced in p.G411S heterozygotes compared to WT and importantly to p.Q456X heterozygotes, which resulted in 50% reduction of PINK1 protein levels. Structural analyses supported our hypothesis that the p.G411S mutation can poison PINK1 WT in a heterodimeric complex and thus effectively reduce cellular PINK1 kinase activity. This in turn impairs the protective functions of the PINK1/PARKIN-mediated mitochondrial quality control. Conclusions: Our study uncovers increased disease risk and molecular mechanisms of a particular heterozygous mutation in a recessive PD gene. Based on genetic and clinical evaluation as well as functional and structural characterization, we established PINK1 p.G411S as a rare genetic risk factor with a relatively large effect size conferred by a dominant negative function phenotype.
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| 16. |
- Sundal, Christina, et al.
(författare)
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Hereditary diffuse leukoencephalopathy with spheroids with phenotype of primary progressive multiple sclerosis
- 2015
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Ingår i: European Journal of Neurology. - : Wiley. - 1351-5101 .- 1468-1331. ; 22:2, s. 328-333
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Tidskriftsartikel (refereegranskat)abstract
- Background and purpose Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is a devastating, hereditary white matter (WM) disorder with heterogeneous neuropsychiatric features. Colony stimulating factor 1 receptor (CSF1R) mutations were looked for in primary progressive multiple sclerosis (PPMS) patients and the clinical features of a family with a novel CSF1R mutation are reported. Methods CSF1R exons 12−22 in a cohort of 220 PPMS patients from the Swedish and Norwegian national multiple sclerosis registries were sequenced. Results One patient had a novel mutation, c.2562T>A; p.Asn854Lys, in the CSF1R gene. Her symptoms started at the age of 29 years with insidious onset of pyramidal weakness in the left leg. The cerebrospinal fluid examination showed four intrathecal immunoglobulin G bands. A magnetic resonance imaging scan performed 4 years after symptom onset demonstrated patchy deep WM lesions. She was diagnosed as having PPMS and treated with intramuscular interferon beta 1a. Due to slow disease progression, the development of memory decline and cerebellar signs, she was given subcutaneous interferon beta 1a without any benefit. The updated pedigree indicated that five siblings also had the CSF1R gene mutation; one was diagnosed with PPMS. Six more distant relatives also had a neurological disorder; four were clinically diagnosed with PPMS. Conclusions Our study indicates that a chronic course of HDLS may mimic PPMS. Genetic testing for CSF1R gene mutations in PPMS cases with a positive family history of neurological disorders may establish the diagnosis of HDLS.
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| 17. |
- Sundal, Christina, et al.
(författare)
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Parkinsonian features in hereditary diffuse leukoencephalopathy with spheroids (HDLS) and CSF1R mutations
- 2013
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Ingår i: Parkinsonism & Related Disorders. - : Elsevier BV. - 1353-8020. ; 19:10, s. 869-877
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Tidskriftsartikel (refereegranskat)abstract
- Atypical Parkinsonism associated with white matter pathology has been described in cerebrovascular diseases, mitochondrial cytopathies, osmotic demyelinating disorders, leukoencephalopathies leukodystrophies, and others. Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is an autosomal dominant disorder with symptomatic onset in midlife and death within a few years after symptom onset. Neuroimaging reveals cerebral white matter lesions that are pathologically characterized by noninflammatory myelin loss, reactive astrocytosis, and axonal spheroids. Most cases are caused by mutations in the colony-stimulating factor 1 receptor (CSF1R) gene. We studied neuropathologically verified HDLS patients with CSF1R mutations to assess parkinsonian features. Ten families were evaluated with 16 affected individuals. During the course of the illness, all patients had at least some degree of bradykinesia. Fifteen patients had postural instability, and seven had rigidity. Two patients initially presented with parkinsonian gait and asymmetrical bradykinesia. These two patients and two others exhibited bradykinesia, rigidity, postural instability, and tremor (two with resting) early in the course of the illness. Levodopa/carbidopa therapy in these four patients provided no benefit, and the remaining 12 patients were not treated. The mean age of onset for all patients was about 45 years (range, 18-71) and the mean disease duration was approximately six years (range, 3-11). We also reviewed HDLS patients published prior to the CSF1R discovery for the presence of parkinsonian features. Out of 50 patients, 37 had gait impairments, 8 rigidity, 7 bradykinesia, and 5 resting tremor. Our report emphasizes the presence of atypical Parkinsonism in HDLS due to CSF1R mutations.
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| 18. |
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| 19. |
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| 20. |
- van der Lee, S. J., et al.
(författare)
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A nonsynonymous mutation in PLCG2 reduces the risk of Alzheimer's disease, dementia with Lewy bodies and frontotemporal dementia, and increases the likelihood of longevity
- 2019
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Ingår i: Acta Neuropathologica. - : Springer Science and Business Media LLC. - 0001-6322 .- 1432-0533. ; 138:2, s. 237-250
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Tidskriftsartikel (refereegranskat)abstract
- The genetic variant rs72824905-G (minor allele) in the PLCG2 gene was previously associated with a reduced Alzheimer's disease risk (AD). The role of PLCG2 in immune system signaling suggests it may also protect against other neurodegenerative diseases and possibly associates with longevity. We studied the effect of the rs72824905-G on seven neurodegenerative diseases and longevity, using 53,627 patients, 3,516 long-lived individuals and 149,290 study-matched controls. We replicated the association of rs72824905-G with reduced AD risk and we found an association with reduced risk of dementia with Lewy bodies (DLB) and frontotemporal dementia (FTD). We did not find evidence for an effect on Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS) risks, despite adequate sample sizes. Conversely, the rs72824905-G allele was associated with increased likelihood of longevity. By-proxy analyses in the UK Biobank supported the associations with both dementia and longevity. Concluding, rs72824905-G has a protective effect against multiple neurodegenerative diseases indicating shared aspects of disease etiology. Our findings merit studying the PLC gamma 2 pathway as drug-target.
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