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Patel A, Dharap A. An Emerging Role for Enhancer RNAs in Brain Disorders. Neuromolecular Med 2024; 26:7. [PMID: 38546891 DOI: 10.1007/s12017-024-08776-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 02/23/2024] [Indexed: 04/02/2024]
Abstract
Noncoding DNA undergoes widespread context-dependent transcription to produce noncoding RNAs. In recent decades, tremendous advances in genomics and transcriptomics have revealed important regulatory roles for noncoding DNA elements and the RNAs that they produce. Enhancers are one such element that are well-established drivers of gene expression changes in response to a variety of factors such as external stimuli, cellular responses, developmental cues, and disease states. They are known to act at long distances, interact with multiple target gene loci simultaneously, synergize with other enhancers, and associate with dynamic chromatin architectures to form a complex regulatory network. Recent advances in enhancer biology have revealed that upon activation, enhancers transcribe long noncoding RNAs, known as enhancer RNAs (eRNAs), that have been shown to play important roles in enhancer-mediated gene regulation and chromatin-modifying activities. In the brain, enhancer dysregulation and eRNA transcription has been reported in numerous disorders from acute injuries to chronic neurodegeneration. Because this is an emerging area, a comprehensive understanding of eRNA function has not yet been achieved in brain disorders; however, the findings to date have illuminated a role for eRNAs in activity-driven gene expression and phenotypic outcomes. In this review, we highlight the breadth of the current literature on eRNA biology in brain health and disease and discuss the challenges as well as focus areas and strategies for future in-depth research on eRNAs in brain health and disease.
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Affiliation(s)
- Ankit Patel
- Department of Molecular Medicine, University of South Florida, Tampa, FL, USA
- Byrd Alzheimer's Center & Research Institute, USF Health Neuroscience Institute, Tampa, FL, USA
| | - Ashutosh Dharap
- Department of Molecular Medicine, University of South Florida, Tampa, FL, USA.
- Byrd Alzheimer's Center & Research Institute, USF Health Neuroscience Institute, Tampa, FL, USA.
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2
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Lambert JC, Ramirez A, Grenier-Boley B, Bellenguez C. Step by step: towards a better understanding of the genetic architecture of Alzheimer's disease. Mol Psychiatry 2023; 28:2716-2727. [PMID: 37131074 PMCID: PMC10615767 DOI: 10.1038/s41380-023-02076-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 04/12/2023] [Accepted: 04/14/2023] [Indexed: 05/04/2023]
Abstract
Alzheimer's disease (AD) is considered to have a large genetic component. Our knowledge of this component has progressed over the last 10 years, thanks notably to the advent of genome-wide association studies and the establishment of large consortia that make it possible to analyze hundreds of thousands of cases and controls. The characterization of dozens of chromosomal regions associated with the risk of developing AD and (in some loci) the causal genes responsible for the observed disease signal has confirmed the involvement of major pathophysiological pathways (such as amyloid precursor protein metabolism) and opened up new perspectives (such as the central role of microglia and inflammation). Furthermore, large-scale sequencing projects are starting to reveal the major impact of rare variants - even in genes like APOE - on the AD risk. This increasingly comprehensive knowledge is now being disseminated through translational research; in particular, the development of genetic risk/polygenic risk scores is helping to identify the subpopulations more at risk or less at risk of developing AD. Although it is difficult to assess the efforts still needed to comprehensively characterize the genetic component of AD, several lines of research can be improved or initiated. Ultimately, genetics (in combination with other biomarkers) might help to redefine the boundaries and relationships between various neurodegenerative diseases.
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Affiliation(s)
- Jean-Charles Lambert
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de risque et déterminants moléculaires des maladies liées au vieillissement, Lille, France.
| | - Alfredo Ramirez
- Division of Neurogenetics and Molecular Psychiatry, Department of Psychiatry and Psychotherapy, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Department of Neurodegenerative diseases and Geriatric Psychiatry, University Hospital Bonn, Medical Faculty, Bonn, Germany
- Department of Psychiatry & Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, San Antonio, TX, USA
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
- Cluster of Excellence Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Benjamin Grenier-Boley
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de risque et déterminants moléculaires des maladies liées au vieillissement, Lille, France
| | - Céline Bellenguez
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de risque et déterminants moléculaires des maladies liées au vieillissement, Lille, France
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3
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Watts JA, Grunseich C, Rodriguez Y, Liu Y, Li D, Burdick J, Bruzel A, Crouch RJ, Mahley RW, Wilson S, Cheung V. A common transcriptional mechanism involving R-loop and RNA abasic site regulates an enhancer RNA of APOE. Nucleic Acids Res 2022; 50:12497-12514. [PMID: 36453989 PMCID: PMC9757052 DOI: 10.1093/nar/gkac1107] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/30/2022] [Accepted: 11/07/2022] [Indexed: 12/03/2022] Open
Abstract
RNA is modified by hundreds of chemical reactions and folds into innumerable shapes. However, the regulatory role of RNA sequence and structure and how dysregulation leads to diseases remain largely unknown. Here, we uncovered a mechanism where RNA abasic sites in R-loops regulate transcription by pausing RNA polymerase II. We found an enhancer RNA, AANCR, that regulates the transcription and expression of apolipoprotein E (APOE). In some human cells such as fibroblasts, AANCR is folded into an R-loop and modified by N-glycosidic cleavage; in this form, AANCR is a partially transcribed nonfunctional enhancer and APOE is not expressed. In contrast, in other cell types including hepatocytes and under stress, AANCR does not form a stable R-loop as its sequence is not modified, so it is transcribed into a full-length enhancer that promotes APOE expression. DNA sequence variants in AANCR are associated significantly with APOE expression and Alzheimer's Disease, thus AANCR is a modifier of Alzheimer's Disease. Besides AANCR, thousands of noncoding RNAs are regulated by abasic sites in R-loops. Together our data reveal the essentiality of the folding and modification of RNA in cellular regulation and demonstrate that dysregulation underlies common complex diseases such as Alzheimer's disease.
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Affiliation(s)
- Jason A Watts
- Department of Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Epigenetics and Stem Cell Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Christopher Grunseich
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yesenia Rodriguez
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Yaojuan Liu
- Department of Pediatrics and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dongjun Li
- Department of Pediatrics and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Joshua T Burdick
- Department of Pediatrics and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alan Bruzel
- Department of Pediatrics and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Robert J Crouch
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Robert W Mahley
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA
- Departments of Pathology and Medicine, University of California, San Francisco, CA, USA
| | - Samuel H Wilson
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Vivian G Cheung
- Department of Pediatrics and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
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4
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Zhou X, Fu AK, Ip NY. APOE signaling in neurodegenerative diseases: an integrative approach targeting APOE coding and noncoding variants for disease intervention. Curr Opin Neurobiol 2021; 69:58-67. [PMID: 33647674 DOI: 10.1016/j.conb.2021.02.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/05/2021] [Accepted: 02/05/2021] [Indexed: 10/22/2022]
Abstract
APOE (apolipoprotein E) is a key regulator of lipid metabolism and a leading genetic risk factor for Alzheimer's disease. While APOE participates in multiple biological pathways, its roles in diseases are largely due to the mutant protein encoded by APOE-ε4. However, emerging evidence suggests that some noncoding Alzheimer's disease risk variants residing in APOE and its nearby regions exert APOE-ε4-independent risks and modify APOE gene expression. Moreover, intervention strategies targeting APOE are being explored. In this review, we summarize the literature on the genetic risks and roles of APOE in biological systems. Moreover, we propose an integrative approach to evaluate disease risk and tailor interventions to aid research on APOE-associated diseases.
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Affiliation(s)
- Xiaopu Zhou
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen-Hong Kong Institute of Brain Science, 518057 Shenzhen, Guangdong, China
| | - Amy Ky Fu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen-Hong Kong Institute of Brain Science, 518057 Shenzhen, Guangdong, China
| | - Nancy Y Ip
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen-Hong Kong Institute of Brain Science, 518057 Shenzhen, Guangdong, China.
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5
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Zhou X, Chen Y, Mok KY, Kwok TCY, Mok VCT, Guo Q, Ip FC, Chen Y, Mullapudi N, Giusti-Rodríguez P, Sullivan PF, Hardy J, Fu AKY, Li Y, Ip NY; Alzheimer’s Disease Neuroimaging Initiative. Non-coding variability at the APOE locus contributes to the Alzheimer's risk. Nat Commun 2019; 10:3310. [PMID: 31346172 DOI: 10.1038/s41467-019-10945-z] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 06/10/2019] [Indexed: 12/30/2022] Open
Abstract
Alzheimer’s disease (AD) is a leading cause of mortality in the elderly. While the coding change of APOE-ε4 is a key risk factor for late-onset AD and has been believed to be the only risk factor in the APOE locus, it does not fully explain the risk effect conferred by the locus. Here, we report the identification of AD causal variants in PVRL2 and APOC1 regions in proximity to APOE and define common risk haplotypes independent of APOE-ε4 coding change. These risk haplotypes are associated with changes of AD-related endophenotypes including cognitive performance, and altered expression of APOE and its nearby genes in the human brain and blood. High-throughput genome-wide chromosome conformation capture analysis further supports the roles of these risk haplotypes in modulating chromatin states and gene expression in the brain. Our findings provide compelling evidence for additional risk factors in the APOE locus that contribute to AD pathogenesis. Several studies show that APOE-ε4 coding variants are associated with Alzheimer’s disease (AD) risk. Here, Zhou et al. perform fine-mapping of the APOE region and find AD risk haplotypes with non-coding variants in the PVRL2 and APOC1 regions that are associated with relevant endophenotypes.
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Chen XQ, Mobley WC. Alzheimer Disease Pathogenesis: Insights From Molecular and Cellular Biology Studies of Oligomeric Aβ and Tau Species. Front Neurosci 2019; 13:659. [PMID: 31293377 PMCID: PMC6598402 DOI: 10.3389/fnins.2019.00659] [Citation(s) in RCA: 174] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 06/07/2019] [Indexed: 01/08/2023] Open
Abstract
Alzheimer disease (AD) represents an oncoming epidemic that without an effective treatment promises to exact extraordinary human and financial burdens. Studies of pathogenesis are essential for defining targets for discovering disease-modifying treatments. Past studies of AD neuropathology provided valuable, albeit limited, insights. Nevertheless, building on these findings, recent studies have provided an increasingly rich harvest of genetic, molecular and cellular data that are creating unprecedented opportunities to both understand and treat AD. Among the most significant are those documenting the presence within the AD brain of toxic oligomeric species of Aβ and tau. Existing data support the view that such species can propagate and spread within neural circuits. To place these findings in context we first review the genetics and neuropathology of AD, including AD in Down syndrome (AD-DS). We detail studies that support the existence of toxic oligomeric species while noting the significant unanswered questions concerning their precise structures, the means by which they spread and undergo amplification and how they induce neuronal dysfunction and degeneration. We conclude by offering a speculative synthesis for how oligomers of Aβ and tau initiate and drive pathogenesis. While 100 years after Alzheimer's first report there is much still to learn about pathogenesis and the discovery of disease-modifying treatments, the application of new concepts and sophisticated new tools are poised to deliver important advances for combatting AD.
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Affiliation(s)
- Xu-Qiao Chen
- Department of Neurosciences, University of California, San Diego, San Diego, CA, United States
| | - William C. Mobley
- Department of Neurosciences, University of California, San Diego, San Diego, CA, United States
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7
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Galmés S, Serra F, Palou A. Vitamin E Metabolic Effects and Genetic Variants: A Challenge for Precision Nutrition in Obesity and Associated Disturbances. Nutrients 2018; 10:E1919. [PMID: 30518135 DOI: 10.3390/nu10121919] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 11/27/2018] [Accepted: 11/30/2018] [Indexed: 02/07/2023] Open
Abstract
Vitamin E (VE) has a recognized leading role as a contributor to the protection of cell constituents from oxidative damage. However, evidence suggests that the health benefits of VE go far beyond that of an antioxidant acting in lipophilic environments. In humans, VE is channeled toward pathways dealing with lipoproteins and cholesterol, underlining its relevance in lipid handling and metabolism. In this context, both VE intake and status may be relevant in physiopathological conditions associated with disturbances in lipid metabolism or concomitant with oxidative stress, such as obesity. However, dietary reference values for VE in obese populations have not yet been defined, and VE supplementation trials show contradictory results. Therefore, a better understanding of the role of genetic variants in genes involved in VE metabolism may be crucial to exert dietary recommendations with a higher degree of precision. In particular, genetic variability should be taken into account in targets concerning VE bioavailability per se or concomitant with impaired lipoprotein transport. Genetic variants associated with impaired VE liver balance, and the handling/resolution of oxidative stress might also be relevant, but the core information that exists at present is insufficient to deliver precise recommendations.
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8
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Bratosiewicz-Wasik J, Liberski PP, Peplonska B, Styczynska M, Smolen-Dzirba J, Cycon M, Wasik TJ. Regulatory region single nucleotide polymorphisms of the apolipoprotein E gene as risk factors for Alzheimer's disease. Neurosci Lett 2018; 684:86-90. [PMID: 29990559 DOI: 10.1016/j.neulet.2018.07.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/26/2018] [Accepted: 07/06/2018] [Indexed: 11/19/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by a complex aetiology. The ε4 allel of the apolipoprotein E gene (APOE) is the only confirmed genetic risk factor for the development of AD. In addition, polymorphisms at the promoter region of the APOE gene are assumed to modulate the susceptibility to AD by their different affinity to the transcription factors thus affecting the expression of the gene. In the presented study, we investigated the association between -491 A/T (rs449647), -427C/T, (rs769446) and -219 T/G (rs405509) single nucleotide polymorphisms (SNPs) of APOE gene and AD risk in the Polish population. We found that only the -491 T allele and -491 A/T genotype acted as protective factors against AD, whereas the -219 T/G heterozygosity increased risk for AD in APOE ε4 carriers but not in APOE ε4 non-carriers. What is more, haplotype frequency estimation showed significant positive for A-T-T-C-C and A-T-G-C-C haplotypes or negative for A-T-T-T-C and T-T-T-T-C haplotypes associations with AD. These results contribute to the evidence that APOE promoter polymorphisms modulate risk for AD.
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Affiliation(s)
- Jolanta Bratosiewicz-Wasik
- Department of Biopharmacy, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland.
| | - Pawel P Liberski
- Department of Molecular Pathology and Neuropathology, Medical University of Lodz, Poland
| | - Beata Peplonska
- Department of Neurodegenerative Disorders, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warszawa, Poland
| | - Maria Styczynska
- Department of Neurodegenerative Disorders, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warszawa, Poland
| | - Joanna Smolen-Dzirba
- Department of Microbiology and Virology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Mariusz Cycon
- Department of Microbiology and Virology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Tomasz J Wasik
- Department of Microbiology and Virology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
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Wang Z, Qin W, Wei CB, Tang Y, Zhao LN, Jin HM, Li Y, Wang Q, Luan XQ, He JC, Jia J. The microRNA-1908 up-regulation in the peripheral blood cells impairs amyloid clearance by targeting ApoE. Int J Geriatr Psychiatry 2018; 33:980-986. [PMID: 29635818 DOI: 10.1002/gps.4881] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/28/2018] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To give a new insight into the mechanism of ApoE dysregulation and microRNA-1908 in Alzheimer's disease (AD). METHODS Plasma ApoE levels were measured in 20 AD patients and 20 healthy controls. THP-1 was maintained in RPMI1640 with 10% fetal bovine serum. Quantitative real-time polymerase chain reaction was performed to detect 13-microRNA and ApoE mRNA in cultured cell lines. Enzyme-linked immunosorbent assay was used to measure human ApoE in the plasma or culture medium of cell lines and also used to quantify the human Aβ42 in the culture medium of cell lines. RESULTS We found plasma ApoE level reduced in AD patients (2.28 vs 3.78 μg/mL, P < .001), and microRNA-1908 was up-regulated in AD patients and was negatively associated with plasma ApoE (r = -0.32, P = .012). In human macrophage cell line THP-1 and astrocytoma cell line U87, microRNA-1908 could inhibit the mRNA and protein levels of ApoE by targeting its 3'untranslated region. Consistently, microRNA-1908 inhibits the ApoE-mediated Aβ clearance. CONCLUSIONS Our study provides new insight into the mechanism of ApoE dysregulation in AD patients, and microRNA-1908 might be a therapeutic target for AD treatment.
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Affiliation(s)
- Z Wang
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - W Qin
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - C B Wei
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - Y Tang
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - L N Zhao
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - H M Jin
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - Y Li
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - Q Wang
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - X Q Luan
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, ZJ, China
| | - J C He
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, ZJ, China
| | - J Jia
- Inovation Center for Neurological Disorders, Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, China.,Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
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10
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Dwivedi S, Madeshiya AK, Singh S, Chandra A, Mahdi AA. Association of APOE − 219G > T and − 427T > C polymorphic variants in transcriptional regulatory region of APOE gene with gallbladder stone: A north Indian case-control study. Meta Gene 2018. [DOI: 10.1016/j.mgene.2018.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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11
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Zhang A, Zhao Q, Xu D, Jiang S. Brain APOE expression quantitative trait loci-based association study identified one susceptibility locus for Alzheimer's disease by interacting with APOE ε4. Sci Rep 2018; 8:8068. [PMID: 29795290 PMCID: PMC5966425 DOI: 10.1038/s41598-018-26398-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 05/08/2018] [Indexed: 02/05/2023] Open
Abstract
Some studies have demonstrated interactions of AD-risk single nucleotide polymorphisms (SNPs) in non-APOE regions with APOE genotype. Nevertheless, no study reported interactions of expression quantitative trait locus (eQTL) for APOE with APOE genotype. In present study, we included 9286 unrelated AD patients and 8479 normal controls from 12 cohorts of NIA Genetics of Alzheimer’s Disease Data Storage Site (NIAGADS) and Alzheimer’s Disease Neuroimaging Initiative (ADNI). 34 unrelated brain eQTLs for APOE were compiled from BRAINEAC and GTEx. We used multi-covariate logistic regression analysis to identify eQTLs interacted with APOE ε4. Adjusted for age and gender, substantia nigra eQTL rs438811 for APOE showed significantly strong interaction with APOE ε4 status (OR, 1.448; CI, 1.124–1.430; P-value = 7.94 × 10−6). APOE ε4-based sub-group analyses revealed that carrying one minor allele T of rs438811 can increase the opportunity of developing to AD by 26.75% in APOE ε4 carriers but not in non-carriers. We revealed substantia nigra eQTL rs438811 for APOE can interact with APOE ε4 and confers risk in APOE ε4 carriers only.
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Affiliation(s)
- Aiqian Zhang
- Department of Gynecology, Third Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Qingnan Zhao
- Department of Pediatrics, The University of Texas MD Anderson Cancer center, Houston, Texas, USA
| | - Dabao Xu
- Department of Gynecology, Third Xiangya Hospital of Central South University, Changsha, Hunan, China.
| | - Shan Jiang
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA.
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12
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Shao Y, Shaw M, Todd K, Khrestian M, D'Aleo G, Barnard PJ, Zahratka J, Pillai J, Yu CE, Keene CD, Leverenz JB, Bekris LM. DNA methylation of TOMM40-APOE-APOC2 in Alzheimer's disease. J Hum Genet 2018; 63:459-471. [PMID: 29371683 DOI: 10.1038/s10038-017-0393-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 10/31/2017] [Accepted: 11/01/2017] [Indexed: 12/12/2022]
Abstract
The apolipoprotein E (APOE) ε4 allele is the major genetic risk factor for Alzheimer's disease (AD). Multiple regulatory elements, spanning the extended TOMM40-APOE-APOC2 region, regulate gene expression at this locus. Regulatory element DNA methylation changes occur under different environmental conditions, such as disease. Our group and others have described an APOE CpG island as hypomethylated in AD, compared to cognitively normal controls. However, little is known about methylation of the larger TOMM40-APOE-APOC2 region. The hypothesis of this investigation was that regulatory element methylation levels of the larger TOMM40-APOE-APOC2 region are associated with AD. The aim was to determine whether DNA methylation of the TOMM40-APOE-APOC2 region differs in AD compared to cognitively normal controls in post-mortem brain and peripheral blood. DNA was extracted from human brain (n = 12) and peripheral blood (n = 67). A methylation array was used for this analysis. Percent methylation within the TOMM40-APOE-APOC2 region was evaluated for differences according to tissue type, disease state, AD-related biomarkers, and gene expression. Results from this exploratory analysis suggest that regulatory element methylation levels within the larger TOMM40-APOE-APOC2 gene region correlate with AD-related biomarkers and TOMM40 or APOE gene expression in AD.
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Affiliation(s)
- Yvonne Shao
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - McKenzie Shaw
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Kaitlin Todd
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Maria Khrestian
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Giana D'Aleo
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - P John Barnard
- Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA
| | - Jeff Zahratka
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Jagan Pillai
- Lou Ruvo Center for Brain Health, Cleveland Clinic, Cleveland, OH, USA
| | - Chang-En Yu
- Department of Pathology, University of Washington School of Medicine, Seattle, WA, USA
| | - C Dirk Keene
- Department of Pathology, University of Washington School of Medicine, Seattle, WA, USA
| | - James B Leverenz
- Lou Ruvo Center for Brain Health, Cleveland Clinic, Cleveland, OH, USA
| | - Lynn M Bekris
- Lerner Research Institute, Genomic Medicine, Cleveland Clinic, Cleveland, OH, USA.
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13
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Parmenter BA, Denney DR, Lynch SG, Middleton LS, Harlan LM. Cognitive impairment in patients with multiple sclerosis: association with the APOE gene and promoter polymorphisms. Mult Scler 2016; 13:25-32. [PMID: 17294608 DOI: 10.1177/1352458506070682] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Background Studies examining the ε4 allele of the APOE gene as a factor affecting the severity of multiple sclerosis (MS) have yielded conflicting results. The focus of these studies on physical disability to the neglect of cognitive impairment is surprising in light of the associations between the ε4 allele and other dementia conditions. Only two studies examine the relationship between the ε4 allele and cognitive impairment. Methods A neuropsychological test battery was administered to 263 MS patients, and their current disability status was evaluated. Genotypes were determined for APOE epsilon and for two promoter region polymorphisms (-219 G/T and -491 A/T). Results Although effects were generally weak, female patients with the -491 AA genotype had a later age of disease onset, lower disability scores, and somewhat higher scores on the cognitive battery. Male patients with the ε2 allele had lower disability and higher scores on the cognitive battery. The ε4 allele was not related to physical disability, and there was no difference between ε4+and ε4– patients in overall cognitive performance. However, when patients with severe cognitive impairment were identified, a greater proportion (52%) of these patients had the ε4 allele than those in the unimpaired group (27%). Conclusion An association with the ε4 allele was evident in this study, but only in cases of severe cognitive impairment.
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Affiliation(s)
- B A Parmenter
- Department of Psychology, 1415 Jayhawk Boulevard, University of Kansas, Lawrence, KS 66045, USA
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14
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Ma C, Zhang Y, Li X, Zhang J, Chen K, Liang Y, Chen Y, Liu Z, Zhang Z. Is there a significant interaction effect between apolipoprotein E rs405509 T/T and ε4 genotypes on cognitive impairment and gray matter volume? Eur J Neurol 2016; 23:1415-25. [PMID: 27259692 DOI: 10.1111/ene.13052] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 04/21/2016] [Indexed: 11/28/2022]
Abstract
BACKGROUND Evidence demonstrates that the T allele of the single-nucleotide polymorphism rs405509 in the apolipoprotein E (APOE) promoter is a risk factor for Alzheimer's disease. However, it is unknown whether rs405509 T allele synergizes with the APOE ε4 allele in influencing cognition and brain structure. METHODS We analyzed the interaction effect of the rs405509 T allele and the APOE ε4 allele on cognitive ability and brain gray matter volume among elderly people. The subjects were grouped into four groups according to APOE and rs405509 genotypes. RESULTS Significant interaction effects were found between rs405509 and APOE on general mental status, memory and attention. Analysis of the whole brain gray matter showed a significantly positive interaction effect between rs405509and APOE on the right inferior temporal gyrus and right fusiform gyrus (alphasim correction P < 0.001). In addition, there was a significant relationship between cognitive ability and gray matter volume. CONCLUSIONS The data indicate that the APOE rs405509 T homozygote modulates the effect of APOE ε4 on both cognitive performance and brain gray matter structure.
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Affiliation(s)
- C Ma
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
| | - Y Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
| | - X Li
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
| | - J Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
| | - K Chen
- Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China.,Banner Alzheimer's Institute, Phoenix, AZ, USA
| | - Y Liang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
| | - Y Chen
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
| | - Z Liu
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
| | - Z Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Beijing Ageing Brain Rejuvenation Initiative Centre, Beijing Normal University, Beijing, China
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15
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Limon-Sztencel A, Lipska-Ziętkiewicz BS, Chmara M, Wasag B, Bidzan L, Godlewska BR, Limon J. The algorithm for Alzheimer risk assessment based on APOE promoter polymorphisms. Alzheimers Res Ther 2016; 8:19. [PMID: 27193889 PMCID: PMC4872351 DOI: 10.1186/s13195-016-0187-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 04/19/2016] [Indexed: 11/10/2022]
Abstract
Background Over the past two decades, the APOE gene and its polymorphisms have been among the most studied risk factors of Alzheimer disease (AD) development; yet, there are discrepancies between various studies regarding their impact. For this reason, the evaluation of the APOE genotype has not been included in the current European Federation of Neurological Societies guidelines for AD diagnosis and management. This aim of this study was to add to this discussion by assessing the possible influence of multiple polymorphisms in the promoter region of the APOE gene and genotypes of its allele E on the risk for dementia. Methods We performed a comprehensive analysis of APOE gene polymorphisms, assessed the detected genotypes and correlated molecular findings with serum apolipoprotein E concentrations. The study comprised 110 patients with AD and 110 age-matched healthy individuals from the Polish population. Results Four polymorphisms of the APOE gene had minor allele frequency exceeding 5 % and were included in the analysis: −491A/T (rs449647), −427T/C (rs769446), −219T/G (rs405509) in the promoter region and +113G/C (rs440446) in intron 1. A protective effect of the −219G allele on AD development was observed. Also, the −491T and −219G alleles were found to be underrepresented in the carriers of the APOE E4 variant. On the basis of the genotype and linkage disequilibrium studies, a relative score was attributed to given genotypes with respect to the estimated probability of their protective effects against AD, giving rise to the ‘preventive score’. This ‘preventive score’, based on the total sums of the relative scores, expresses the protective effect deriving from the synergistic action of individual single-nucleotide polymorphisms. The ‘preventive score’ was identified as an independent predictive factor. Conclusions We propose a novel, more complex approach to AD risk assessment based on the additive effect of multiple polymorphic loci within the APOE promoter region, which on their own may have too weak an impact to reach the level of significance. This has potentially practical implications, as it may help to improve the informative potential of APOE testing in a clinical setting. Subsequent studies of the proposed system in large, multi-ethnic cohorts are necessary for its validation and to assess its potential practical value for clinical applications. Electronic supplementary material The online version of this article (doi:10.1186/s13195-016-0187-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Beata S Lipska-Ziętkiewicz
- Department of Biology and Genetics, Medical University of Gdansk, Debinki 1 Street, 80-210, Gdansk, Poland
| | - Magdalena Chmara
- Department of Biology and Genetics, Medical University of Gdansk, Debinki 1 Street, 80-210, Gdansk, Poland
| | - Bartosz Wasag
- Department of Biology and Genetics, Medical University of Gdansk, Debinki 1 Street, 80-210, Gdansk, Poland
| | - Leszek Bidzan
- Department of Developmental, Psychotic, and Geriatric Psychiatry, Medical University of Gdansk, Debinki 7 Street, 80-952, Gdansk, Poland
| | - Beata R Godlewska
- University Department of Psychiatry, University of Oxford, Oxford, OX3 7JX, UK
| | - Janusz Limon
- Department of Biology and Genetics, Medical University of Gdansk, Debinki 1 Street, 80-210, Gdansk, Poland.
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Berto S, Perdomo-Sabogal A, Gerighausen D, Qin J, Nowick K. A Consensus Network of Gene Regulatory Factors in the Human Frontal Lobe. Front Genet 2016; 7:31. [PMID: 27014338 PMCID: PMC4782181 DOI: 10.3389/fgene.2016.00031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 02/18/2016] [Indexed: 01/29/2023] Open
Abstract
Cognitive abilities, such as memory, learning, language, problem solving, and planning, involve the frontal lobe and other brain areas. Not much is known yet about the molecular basis of cognitive abilities, but it seems clear that cognitive abilities are determined by the interplay of many genes. One approach for analyzing the genetic networks involved in cognitive functions is to study the coexpression networks of genes with known importance for proper cognitive functions, such as genes that have been associated with cognitive disorders like intellectual disability (ID) or autism spectrum disorders (ASD). Because many of these genes are gene regulatory factors (GRFs) we aimed to provide insights into the gene regulatory networks active in the human frontal lobe. Using genome wide human frontal lobe expression data from 10 independent data sets, we first derived 10 individual coexpression networks for all GRFs including their potential target genes. We observed a high level of variability among these 10 independently derived networks, pointing out that relying on results from a single study can only provide limited biological insights. To instead focus on the most confident information from these 10 networks we developed a method for integrating such independently derived networks into a consensus network. This consensus network revealed robust GRF interactions that are conserved across the frontal lobes of different healthy human individuals. Within this network, we detected a strong central module that is enriched for 166 GRFs known to be involved in brain development and/or cognitive disorders. Interestingly, several hubs of the consensus network encode for GRFs that have not yet been associated with brain functions. Their central role in the network suggests them as excellent new candidates for playing an essential role in the regulatory network of the human frontal lobe, which should be investigated in future studies.
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Affiliation(s)
- Stefano Berto
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University LeipzigLeipzig, Germany; Paul-Flechsig Institute for Brain Research, University of LeipzigLeipzig, Germany; Department of Neuroscience, University of Texas Southwestern Medical CenterDallas, TX, USA
| | - Alvaro Perdomo-Sabogal
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig Leipzig, Germany
| | - Daniel Gerighausen
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig Leipzig, Germany
| | - Jing Qin
- Department of Mathematics and Computer Sciences, University of Southern DenmarkOdense, Denmark; Institute for Theoretical Chemistry, University of ViennaVienna, Austria
| | - Katja Nowick
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University LeipzigLeipzig, Germany; Paul-Flechsig Institute for Brain Research, University of LeipzigLeipzig, Germany
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17
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Vasunilashorn S, Ngo L, Kosar CM, Fong TG, Jones RN, Inouye SK, Marcantonio ER. Does Apolipoprotein E Genotype Increase Risk of Postoperative Delirium? Am J Geriatr Psychiatry 2015; 23:1029-1037. [PMID: 26238230 PMCID: PMC4591079 DOI: 10.1016/j.jagp.2014.12.192] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/24/2014] [Accepted: 12/02/2014] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To determine whether apolipoprotein E (ApoE) is associated with postoperative delirium incidence, severity, and duration in older patients free of dementia at baseline. METHODS The authors examined 557 nondemented patients aged 70 years or older undergoing major noncardiac surgery enrolled in the Successful Aging after Elective Surgery Study. Three ApoE measures were considered: ε2, ε4 carriers versus noncarriers, and a three-category ApoE measure. Delirium was determined using the Confusion Assessment Method (CAM) and chart review. We used generalized linear models to estimate the association between ApoE and delirium incidence, severity (peak CAM Severity [CAM-S] score), and days. RESULTS ApoE ε2 and ε4 was present in 15% and 19%, respectively, and postoperative delirium occurred in 24%. Among patients with delirium, the mean peak CAM-S score was 8.0 (standard deviation: 4), with most patients experiencing 1 or 2 delirium days (51% or 28%, respectively). After adjusting for age, sex, surgical procedure, and preoperative cognitive function, ApoE ε4 and ε2 carrier status were not associated with postoperative delirium: RR for ε4=1.0, 95% CI: 0.7-1.5 and RR for ε2=0.9, 95% CI: 0.6-1.4. No association between ApoE and delirium severity or number of delirium days was observed. CONCLUSION In older surgery patients free of dementia, our findings do not support the hypothesis that the ApoE genotype does not confer either risk or protection in postoperative delirium incidence, severity, or duration. Thus, an important genetic risk factor for Alzheimer disease does not affect risk of delirium.
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Affiliation(s)
- Sarinnapha Vasunilashorn
- Division of General Medicine and Primary Care, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts,Aging Brain Center, Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Long Ngo
- Division of General Medicine and Primary Care, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Cyrus M. Kosar
- Aging Brain Center, Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts
| | - Tamara G. Fong
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts,Aging Brain Center, Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Richard N. Jones
- Aging Brain Center, Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts,Department of Psychiatry and Human Behavior, Warren Alpert Medical School, Brown University, Providence, Rhode Island
| | - Sharon K. Inouye
- Division of Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts,Aging Brain Center, Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Edward R. Marcantonio
- Division of General Medicine and Primary Care, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts,Division of Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts,Aging Brain Center, Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
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18
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Yin C, Huang GF, Ruan J, He ZZ, Sun XC. The APOE promoter polymorphism is associated with rebleeding after spontaneous SAH in a Chinese population. Gene 2015; 563:52-5. [PMID: 25752291 DOI: 10.1016/j.gene.2015.03.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/09/2015] [Accepted: 03/04/2015] [Indexed: 12/30/2022]
Affiliation(s)
- Cheng Yin
- Department of Neurosurgery, Hospital of the University of Electronic Science and Technology of China, Sichuan Provincial People's Hospital, Chengdu 610072, PR China
| | - Guang-fu Huang
- Department of Neurosurgery, Hospital of the University of Electronic Science and Technology of China, Sichuan Provincial People's Hospital, Chengdu 610072, PR China
| | - Jian Ruan
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China
| | - Zong-ze He
- Department of Neurosurgery, Hospital of the University of Electronic Science and Technology of China, Sichuan Provincial People's Hospital, Chengdu 610072, PR China
| | - Xiao-chuan Sun
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China.
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Chouinard-Watkins R, Plourde M. Fatty acid metabolism in carriers of apolipoprotein E epsilon 4 allele: is it contributing to higher risk of cognitive decline and coronary heart disease? Nutrients 2014; 6:4452-71. [PMID: 25333200 PMCID: PMC4210928 DOI: 10.3390/nu6104452] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/02/2014] [Accepted: 09/24/2014] [Indexed: 01/01/2023] Open
Abstract
Apolipoprotein E (ApoE) is a protein playing a pivotal role in lipid homeostasis since it regulates cholesterol, triglyceride and phospholipid metabolism in the blood and the brain. APOE gene regulates the expression of this protein and has three different alleles: ε2, ε3 and ε4. Carrying an APOE4 allele is recognised as a genetic risk factor of late-onset Alzheimer’s disease (LOAD) and coronary heart disease (CHD). Consuming fatty fish, rich in long chain omega-3 fatty acids (LC omega-3), seems to be associated with risk reduction of developing LOAD and CHD but this link seems not to hold in APOE4 carriers, at least in LOAD. In CHD trials, APOE4 carriers supplemented with LC omega-3 were categorized as differential responders to the treatment with regards to CHD risk markers. This is potentially because fatty acid metabolism is disturbed in APOE4 carriers compared to the non-carriers. More specifically, homeostasis of LC omega-3 is disrupted in carriers of APOE4 allele and this is potentially because they β-oxidize more LC omega-3 than the non-carriers. Therefore, there is a potential shift in fatty acid selection for β-oxidation towards LC omega-3 which are usually highly preserved for incorporation into cell membranes.
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Affiliation(s)
- Raphaël Chouinard-Watkins
- Research Center on Aging, Health and Social Services Centre-University Institute of Geriatrics of Sherbrooke, Department of medicine, Université de Sherbrooke, 1036 Belvédère Sud, Sherbrooke, J1H 4C4, Canada.
| | - Mélanie Plourde
- Research Center on Aging, Health and Social Services Centre-University Institute of Geriatrics of Sherbrooke, Department of medicine, Université de Sherbrooke, 1036 Belvédère Sud, Sherbrooke, J1H 4C4, Canada.
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20
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Lien E, Andersen GL, Bao Y, Gordish-Dressman H, Skranes J, Blackman JA, Vik T. Gene sequences regulating the production of apoE and cerebral palsy of variable severity. Eur J Paediatr Neurol 2014; 18:591-6. [PMID: 24786335 PMCID: PMC4160538 DOI: 10.1016/j.ejpn.2014.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 03/04/2014] [Accepted: 04/04/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND The apoE protein is the most important lipid transporter in the brain and has also been shown to have several regulatory functions in the central nervous system. The production of apoE is regulated by a number of genes and increases under certain conditions such as cerebral injury in adults. AIMS Our aim was to study whether variations in genes regulating the expression of the APOE gene were associated with severity of cerebral palsy (CP). METHODS Children enrolled in the Cerebral Palsy Register of Norway (CPRN) were invited to participate in this cross-sectional study; 281 of the invited 703 children (40%) returned swabs with buccal cells collected by parents. Six genetic variations thought to affect the production of apoE were genotyped and correlated with clinical data recorded in the CPRN. RESULTS Compared with children carrying the GG allele, children with genotype GT or TT in a specific genetic variation (rs59007384 located in the nearby TOMM40 gene) had excess risk for worse fine motor function (Odds ratio (OR): 1.82; 95% Confidence interval (CI): 1.10-2.99; p = 0.019) and epilepsy (OR: 2.32; CI: 1.17-4.61; p = 0.016). There was no association between severity of CP and any of the other five genetic variations analyzed. CONCLUSION Our findings suggest that genetic variations in one of the sequences regulating the expression of APOE, may be associated with worse clinical outcome in children with cerebral palsy.
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Affiliation(s)
- Espen Lien
- Department of Laboratory Medicine, Children's and Women's Health, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Department of Pediatrics, St. Olavs Hospital, University Hospital of Trondheim, Trondheim, Norway.
| | - Guro L Andersen
- Vestfold Hospital Trust, The Cerebral Palsy Register of Norway, Tønsberg, Norway
| | - Yongde Bao
- DNA Science Core, Univ. of Virginia School of Medicine, Charlottesville, VA, USA
| | - Heather Gordish-Dressman
- George Washington University School of Medicine and Health Sciences, Research Center for Genetic Medicine, Children's National Medical Center, Washington, DC, USA
| | - Jon Skranes
- Department of Laboratory Medicine, Children's and Women's Health, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - James A Blackman
- Department of Pediatrics, University of Virginia, Charlottesville, VA, USA; Cerebral Palsy International Research Foundation, Princeton Junction, NJ, USA
| | - Torstein Vik
- Department of Laboratory Medicine, Children's and Women's Health, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway
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21
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Meinitzer A, Tomaschitz A, Pilz S, Truber M, Zechner G, Gaksch M, Prietl B, Treiber G, Schwarz M, Baranyi A. Development of a liquid chromatography–mass spectrometry method for the determination of the neurotoxic quinolinic acid in human serum. Clin Chim Acta 2014; 436:268-72. [DOI: 10.1016/j.cca.2014.06.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 06/13/2014] [Accepted: 06/13/2014] [Indexed: 12/14/2022]
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22
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Mills JD, Sheahan PJ, Lai D, Kril JJ, Janitz M, Sutherland GT. The alternative splicing of the apolipoprotein E gene is unperturbed in the brains of Alzheimer’s disease patients. Mol Biol Rep 2014; 41:6365-76. [DOI: 10.1007/s11033-014-3516-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Accepted: 06/19/2014] [Indexed: 12/20/2022]
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23
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Jackson HM, Soto I, Graham LC, Carter GW, Howell GR. Clustering of transcriptional profiles identifies changes to insulin signaling as an early event in a mouse model of Alzheimer's disease. BMC Genomics 2013; 14:831. [PMID: 24274089 PMCID: PMC3907022 DOI: 10.1186/1471-2164-14-831] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 11/14/2013] [Indexed: 11/23/2022] Open
Abstract
Background Alzheimer’s disease affects more than 35 million people worldwide but there is no known cure. Age is the strongest risk factor for Alzheimer’s disease but it is not clear how age-related changes impact the disease. Here, we used a mouse model of Alzheimer’s disease to identify age-specific changes that occur prior to and at the onset of traditional Alzheimer-related phenotypes including amyloid plaque formation. To identify these early events we used transcriptional profiling of mouse brains combined with computational approaches including singular value decomposition and hierarchical clustering. Results Our study identifies three key events in early stages of Alzheimer’s disease. First, the most important drivers of Alzheimer’s disease onset in these mice are age-specific changes. These include perturbations of the ribosome and oxidative phosphorylation pathways. Second, the earliest detectable disease-specific changes occur to genes commonly associated with the hypothalamic-adrenal-pituitary (HPA) axis. These include the down-regulation of genes relating to metabolism, depression and appetite. Finally, insulin signaling, in particular the down-regulation of the insulin receptor substrate 4 (Irs4) gene, may be an important event in the transition from age-related changes to Alzheimer’s disease specific-changes. Conclusion A combination of transcriptional profiling combined with computational analyses has uncovered novel features relevant to Alzheimer’s disease in a widely used mouse model and offers avenues for further exploration into early stages of AD.
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Affiliation(s)
- Harriet M Jackson
- The Jackson Laboratory, 600 Main Street, Bar Harbor, Maine 04609, USA.
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Abstract
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder characterized by loss of memory and cognitive function. A key neuropathological event in AD is the accumulation of amyloid-β (Aβ) peptide. The production and clearance of Aβ in the brain are regulated by a large group of genes. The expression levels of these genes must be fine-tuned in the brain to keep Aβ at a balanced amount under physiological condition. Misregulation of AD genes has been found to either increase AD risk or accelerate the disease progression. In recent years, important progress has been made in uncovering the regulatory elements and transcriptional factors that guide the expression of these genes. In this review, we describe the mechanisms of transcriptional regulation for the known AD genes and the misregualtion that leads to AD susceptibility.
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Affiliation(s)
- Xiao-Fen Chen
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, 361102 Xiamen, Fujian, People's Republic of China.
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Nowak A, Przybylowska-Sygut K, Gacek M, Kaminska A, Szaflik JP, Szaflik J, Majsterek I. Neurodegenerative Genes Polymorphisms of the -491A/T APOE, the -877T/C APP and the Risk of Primary Open-angle Glaucoma in the Polish Population. Ophthalmic Genet 2013; 36:105-12. [PMID: 24073598 DOI: 10.3109/13816810.2013.838277] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Glaucoma is characterized by optic neuropathy of the retinal ganglion cell. It may be possible that β-amyloid (Aβ) and apolipoprotein E (APOE), the main proteins of the pathogenesis of AD, play a role in glaucoma development. The aim of this study was to evaluate a relationship between the APP and APOE gene polymorphisms and the risk of primary open-angle glaucoma (POAG) occurrence. MATERIALS AND METHODS The study consisted of 183 patients with POAG and 209 healthy subjects. Genomic DNA was extracted from peripheral blood. Analysis of the gene polymorphisms was performed using PCR-RFLP. RESULTS We found a statistically significant increase of the -491 T allele frequency (p=0.02; OR=1.48; 95% CI=1.06-2.08) of APOE in POAG compared to healthy controls. There were no differences in the genotype and allele distributions and odds ratios of the APP polymorphism between patients and controls group. We also found an association between APOE polymorphic variant and retinal nerve fiber layer (RNFL). There was a statistically significant difference in the APOE gene A/T genotype frequency in the early POAG stage and middle-advanced POAG stage in comparison to the advanced POAG stage (p=0.04; OR=3.38; 95% CI=1.04-10.97). CONCLUSIONS The -491 T allele of APOE polymorphism may be associated with a risk of POAG occurrence in the Polish population.
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Affiliation(s)
- Alicja Nowak
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz , Poland and
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Chouinard-Watkins R, Rioux-Perreault C, Fortier M, Tremblay-Mercier J, Zhang Y, Lawrence P, Vohl MC, Perron P, Lorrain D, Brenna JT, Cunnane SC, Plourde M. Disturbance in uniformly 13C-labelled DHA metabolism in elderly human subjects carrying the apoE ε4 allele. Br J Nutr 2013; 110:1751-9. [PMID: 23631810 DOI: 10.1017/S0007114513001268] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Carrying the apoE ε4 allele (E4+ ) is the most important genetic risk for Alzheimer’s disease. Unlike non-carriers (E4- ), E4+ seem not to be protected against Alzheimer's disease when consuming fish. We hypothesised that this may be linked to a disturbance in n-3 DHA metabolism in E4+. The aim of the present study was to evaluate [13C]DHA metabolism over 28 d in E4+ v. E4-. A total of forty participants (twenty-six women and fourteen men) received a single oral dose of 40 mg [13C]DHA, and its metabolism was monitored in blood and breath over 28 d. Of the participants, six were E4+ and thirty-four were E4-. In E4+, mean plasma [13C]DHA was 31% lower than that in E4-, and cumulative b-oxidation of [13C]DHA was higher than that in E4- 1–28 d post-dose (P ≤0·05). A genotype x time interaction was detected for cumulative b-oxidation of [13C]DHA (P ≤ 0·01). The whole-body half-life of [13C]DHA was 77% lower in E4+ compared with E4- (P ≤0·01). In E4+ and E4-, the percentage dose of [13C]DHA recovered/h as 13CO2 correlated with [13C]DHA concentration in plasma, but the slope of linear regression was 117% steeper in E4+ compared with E4- (P ≤ 0·05). These results indicate that DHA metabolism is disturbed in E4+, and may help explain why there is no association between DHA levels in plasma and cognition in E4+. However, whether E4+ disturbs the metabolism of 13C-labelled fatty acids other than DHA cannot be deduced from the present study.
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Jun G, Vardarajan BN, Buros J, Yu CE, Hawk MV, Dombroski BA, Crane PK, Larson EB, Mayeux R, Haines JL, Lunetta KL, Pericak-Vance MA, Schellenberg GD, Farrer LA. Comprehensive search for Alzheimer disease susceptibility loci in the APOE region. ACTA ACUST UNITED AC 2013; 69:1270-9. [PMID: 22869155 DOI: 10.1001/archneurol.2012.2052] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE To evaluate the association of risk and age at onset (AAO) of Alzheimer disease (AD) with single-nucleotide polymorphisms (SNPs) in the chromosome 19 region including apolipoprotein E (APOE) and a repeat-length polymorphism in TOMM40 (poly-T, rs10524523). DESIGN Conditional logistic regression models and survival analysis. SETTING Fifteen genome-wide association study data sets assembled by the Alzheimer's Disease Genetics Consortium. PARTICIPANTS Eleven thousand eight hundred forty AD cases and 10 931 cognitively normal elderly controls. MAIN OUTCOME MEASURES Association of AD risk and AAO with genotyped and imputed SNPs located in an 800-Mb region including APOE in the entire Alzheimer's Disease Genetics Consortium data set and with the TOMM40 poly-T marker genotyped in a subset of 1256 cases and 1605 controls. RESULTS In models adjusting for APOE ε4, no SNPs in the entire region were significantly associated with AAO at P.001. Rs10524523 was not significantly associated with AD or AAO in models adjusting for APOE genotype or within the subset of ε3/ε3 subjects. CONCLUSIONS APOE alleles ε2, ε3, and ε4 account for essentially all the inherited risk of AD associated with this region. Other variants including a poly-T track in TOMM40 are not independent risk or AAO loci.
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Affiliation(s)
- Gyungah Jun
- Department of Medicine (Biomedical Genetics), Boston University Schools of Medicine and Public Health, Boston, MA, USA
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Abstract
Uncovering the genetic risk and protective factors for complex diseases is of fundamental importance for advancing therapeutic and biomarker discoveries. This endeavor is particularly challenging for neuropsychiatric diseases where diagnoses predominantly rely on the clinical presentation, which may be heterogeneous, possibly due to the heterogeneity of the underlying genetic susceptibility factors and environmental exposures. Although genome-wide association studies of various neuropsychiatric diseases have recently identified susceptibility loci, there likely remain additional genetic risk factors that underlie the liability to these conditions. Furthermore, identification and characterization of the causal risk variant(s) in each of these novel susceptibility loci constitute a formidable task, particularly in the absence of any prior knowledge about their function or mechanism of action. Biologically relevant, quantitative phenotypes, i.e., endophenotypes, provide a powerful alternative to the more traditional, binary disease phenotypes in the discovery and characterization of susceptibility genes for neuropsychiatric conditions. In this review, we focus on Alzheimer's disease (AD) as a model neuropsychiatric disease and provide a synopsis of the recent literature on the use of endophenotypes in AD genetics. We highlight gene expression, neuropathology and cognitive endophenotypes in AD, with examples demonstrating the utility of these alternative approaches in the discovery of novel susceptibility genes and pathways. In addition, we discuss how these avenues generate testable hypothesis about the pathophysiology of genetic factors that have far-reaching implications for therapies.
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Affiliation(s)
- Nilüfer Ertekin-Taner
- Departments of Neurology and Neuroscience, Mayo Clinic Florida, 4500 San Pablo Road, Birdsall 3, Jacksonville, FL 32224 USA
| | - Phillip L. De Jager
- Departments of Neurology and Psychiatry, Program in Translational NeuroPsychiatric Genomics, Institute for the Neurosciences, Brigham and Women’s Hospital, 77 Avenue Louis Pasteur NRB168, Boston, MA 02115 USA
- Harvard Medical School, Boston, MA 02115 USA
- Program in Medical and Population Genetics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142 USA
| | - Lei Yu
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL 60612 USA
| | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL 60612 USA
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McIntosh AM, Bennett C, Dickson D, Anestis SF, Watts DP, Webster TH, Fontenot MB, Bradley BJ. The apolipoprotein E (APOE) gene appears functionally monomorphic in chimpanzees (Pan troglodytes). PLoS One 2012; 7:e47760. [PMID: 23112842 PMCID: PMC3480407 DOI: 10.1371/journal.pone.0047760] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 09/20/2012] [Indexed: 12/21/2022] Open
Abstract
Background The human apolipoprotein E (APOE) gene is polymorphic, with three primary alleles (E2, E3, E4) that differ at two key non-synonymous sites. These alleles are functionally different in how they bind to lipoproteins, and this genetic variation is associated with phenotypic variation for several medical traits, including cholesterol levels, cardiovascular health, Alzheimer’s disease risk, and longevity. The relative frequencies of these alleles vary across human populations, and the evolution and maintenance of this diversity is much debated. Previous studies comparing human and chimpanzee APOE sequences found that the chimpanzee sequence is most similar to the human E4 allele, although the resulting chimpanzee protein might function like the protein coded for by the human E3 allele. However, these studies have used sequence data from a single chimpanzee and do not consider whether chimpanzees, like humans, show intra-specific and subspecific variation at this locus. Methodology and Principal Findings To examine potential intraspecific variation, we sequenced the APOE gene of 32 chimpanzees. This sample included 20 captive individuals representing the western subspecies (P. troglodytes verus) and 12 wild individuals representing the eastern subspecies (P. t. schweinfurthii). Variation in our resulting sequences was limited to one non-coding, intronic SNP, which showed fixed differences between the two subspecies. We also compared APOE sequences for all available ape genera and fossil hominins. The bonobo APOE protein is identical to that of the chimpanzee, and the Denisovan APOE exhibits all four human-specific, non-synonymous changes and appears functionally similar to the human E4 allele. Conclusions We found no coding variation within and between chimpanzee populations, suggesting that the maintenance of functionally diverse APOE polymorphisms is a unique feature of human evolution.
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Affiliation(s)
- Annick M. McIntosh
- Department of Anthropology, Yale University, New Haven, Connecticut, United States of America
| | - Calvin Bennett
- Department of Anthropology, Yale University, New Haven, Connecticut, United States of America
| | - Dara Dickson
- Department of Anthropology, Yale University, New Haven, Connecticut, United States of America
| | - Stephanie F. Anestis
- Department of Anthropology, Yale University, New Haven, Connecticut, United States of America
| | - David P. Watts
- Department of Anthropology, Yale University, New Haven, Connecticut, United States of America
| | - Timothy H. Webster
- Department of Anthropology, Yale University, New Haven, Connecticut, United States of America
| | - M. Babette Fontenot
- Division of Behavioral Sciences, New Iberia Research Center, University of Louisiana at Lafayette, Lafayette, Louisiana, United States of America
| | - Brenda J. Bradley
- Department of Anthropology, Yale University, New Haven, Connecticut, United States of America
- * E-mail:
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Simon R, Girod M, Fonbonne C, Salvador A, Clément Y, Lantéri P, Amouyel P, Lambert JC, Lemoine J. Total ApoE and ApoE4 isoform assays in an Alzheimer's disease case-control study by targeted mass spectrometry (n=669): a pilot assay for methionine-containing proteotypic peptides. Mol Cell Proteomics 2012; 11:1389-403. [PMID: 22918225 DOI: 10.1074/mcp.m112.018861] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Allelic polymorphism of the apolipoprotein E (ApoE) gene (ApoE ε2, ApoE ε3 and ApoE ε4 alleles) gives rise to three protein isoforms (ApoE2, ApoE3 and ApoE4) that differ by 1 or 2 amino acids. Inheritance of the ApoE ε4 allele is a risk factor for developing Alzheimer's disease (AD). The potential diagnostic value of ApoE protein levels in biological fluids (i.e. cerebrospinal fluid, plasma and serum) for distinguishing between AD patients and healthy elderly subjects is subject to great controversy. Although a recent study reported subnormal total ApoE and ApoE4 levels in the plasma of AD patients, other studies have found normal or even elevated protein levels (versus controls). Because all previously reported assays were based on immunoenzymatic techniques, we decided to develop an orthogonal assay based on targeted mass spectrometry by tracking (i) a proteotypic peptide common to all ApoE isoforms and (ii) a peptide that is specific for the ε4 allele. After trypsin digestion, the ApoE4-specific peptide contains an oxidation-prone methionine residue. The endogenous methionine oxidation level was evaluated in a small cohort (n=68) of heterozygous ε3ε4 carriers containing both healthy controls and AD patients. As expected, the proportion of oxidized residues varied from 0 to 10%, with an average of 5%. We therefore developed a standardized strategy for the unbiased, absolute quantification of ApoE4, based on performic acid oxidization of methionine. Once the sample workflow had been thoroughly validated, it was applied to the concomitant quantification of total ApoE and ApoE4 isoform in a large case-control study (n=669). The final measurements were consistent with most previously reported ApoE concentration values and confirm the influence of the different alleles on the protein expression level. Our results illustrate (i) the reliability of selected reaction monitoring-based assays and (ii) the value of the oxidization step for unbiased monitoring of methionine-containing proteotypic peptides. Furthermore, a statistical analysis indicated that neither total ApoE and ApoE4 levels nor the ApoE/ApoE4 ratio correlated with the diagnosis of AD. These findings reinforce the conclusions of previous studies in which plasma ApoE levels had no obvious clinical significance.
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Affiliation(s)
- Romain Simon
- Institut des Sciences Analytiques, UMR n° 5280 CNRS Université Lyon 1, Université de Lyon, France
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31
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Abstract
Apolipoprotein E (apoE) is a major structural apolipoprotein of several lipoprotein classes. Over the last 13 years, numerous studies have focused on the question whether human apoE affects bone phenotypes and, more recently, whether apoE regulates bone metabolism in mice. Here, we first provide a brief background introduction into the structure, established physiological and pathophysiological functions of apoE, and will then discuss the new aspects of the emerging role of apoE in bone.
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Affiliation(s)
- Andreas Niemeier
- Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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32
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Bañares VG, Bardach A, Peterson G, Tavella MJ, Schreier LE. APOE −491 T allele may reduce the risk of atherosclerotic lesions among middle-aged women. Mol Cell Biochem 2011; 362:123-31. [DOI: 10.1007/s11010-011-1134-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 10/22/2011] [Indexed: 01/10/2023]
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Abstract
Genetic variation within the apolipoprotein E gene (APOE) locus is associated with late-onset Alzheimer's disease risk and quantitative traits as well as apoE expression in multiple tissues. The aim of this investigation was to explore the influence of APOE locus cis-regulatory element enhancer region genetic variation on regional gene promoter activity. Luciferase reporter constructs containing haplotypes of APOE locus gene promoters; APOE, APOC1, and TOMM40, and regional putative enhancers; TOMM40 IVS2-4, TOMM40 IVS6 poly-T, as well as previously described enhancers; ME1, or BCR, were evaluated for their effects on luciferase activity in 3 human cell lines. Results of this investigation demonstrate that in SHSY5Y cells, the APOE promoter is significantly influenced by the TOMM40 IVS2-4 and ME1 and the TOMM40 promoter is significantly influenced by the TOMM40 IVS6 poly-T, ME1 and BCR. In HepG2 cells, theTOMM40 promoter is significantly influenced by all four enhancers, whereas the APOE promoter is not influenced by any of the enhancers. The main novel finding of this investigation was that multiple APOE locus cis-elements influence both APOE and TOMM40 promoter activity according to haplotype and cell type suggesting that a complex transcriptional regulatory structure modulates regional expression.
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Affiliation(s)
- Lynn M Bekris
- Geriatric Research, Education and Clinical Center, VA Puget Sound Health Care System, 1660 South Columbian Way, Seattle, WA 98108, USA..
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Geng H, Law PPY, Ng MCY, Li T, Liang LY, Ge TF, Wong KB, Liang C, Ma RC, So WY, Chan JCN, Ho YY. APOE genotype-function relationship: evidence of -491 A/T promoter polymorphism modifying transcription control but not type 2 diabetes risk. PLoS One 2011; 6:e24669. [PMID: 22028770 PMCID: PMC3196492 DOI: 10.1371/journal.pone.0024669] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 08/18/2011] [Indexed: 12/04/2022] Open
Abstract
Background The apolipoprotein E gene (APOE) coding polymorphism modifies the risks of Alzheimer's disease, type 2 diabetes, and coronary heart disease. Aside from the coding variants, single nucleotide polymorphism (SNP) of the APOE promoter has also been shown to modify the risk of Alzheimer's disease. Methodology/Principal Findings In this study we investigate the genotype-function relationship of APOE promoter polymorphism at molecular level and at physiological level: i.e., in transcription control of the gene and in the risk of type 2 diabetes. In molecular studies, the effect of the APOE −491A/T (rs449647) polymorphism on gene transcription was accessed by dual-luciferase reporter gene assays. The −491 A to T substitution decreased the activity (p<0.05) of the cloned APOE promoter (−1017 to +406). Using the −501 to −481 nucleotide sequence of the APOE promoter as a ‘bait’ to screen the human brain cDNA library by yeast one-hybrid system yielded ATF4, an endoplasmic reticulum stress response gene, as one of the interacting factors. Electrophoretic-mobility-shift assays (EMSA) and chromatin immuno-precipitation (ChIP) analyses further substantiated the physical interaction between ATF4 and the APOE promoter. Over-expression of ATF4 stimulated APOE expression whereas siRNA against ATF4 suppressed the expression of the gene. However, interaction between APOE promoter and ATF4 was not −491A/T-specific. At physiological level, the genotype-function relationship of APOE promoter polymorphism was studied in type 2 diabetes. In 630 cases and 595 controls, three APOE promoter SNPs −491A/T, −219G/T (rs405509), and +113G/C (rs440446) were genotyped and tested for association with type 2 diabetes in Hong Kong Chinese. No SNP or haplotype association with type 2 diabetes was detected. Conclusions/Significance At molecular level, polymorphism −491A/T and ATF4 elicit independent control of APOE gene expression. At physiological level, no genotype-risk association was detected between the studied APOE promoter SNPs and type 2 diabetes in Hong Kong Chinese.
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Affiliation(s)
- Hua Geng
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Peggy P. Y. Law
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Maggie C. Y. Ng
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Ting Li
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Li-Yun Liang
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Tian-Fang Ge
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Kam-Bo Wong
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Chun Liang
- Department of Biochemistry, Hong Kong University of Science and Technology, Hong Kong, China
| | - Ronald C. Ma
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Wing-Yee So
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Juliana C. N. Chan
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Yuan-Yuan Ho
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
- Genetics of Complex Disorder Program, Departments of Biostatistics and Psychiatry, Columbia University, New York, New York, United States of America
- * E-mail:
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Fu YH, Lv RJ, Jin LR, Lu Q, Shao XQ, He JS, Wu LW, Zhang LS, Hu HG. Association of apolipoprotein E polymorphisms with temporal lobe epilepsy in a Chinese Han population. Epilepsy Res 2011; 91:253-9. [PMID: 20810250 DOI: 10.1016/j.eplepsyres.2010.07.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Revised: 07/14/2010] [Accepted: 07/25/2010] [Indexed: 11/16/2022]
Abstract
Apolipoprotein E (ApoE) has been implicated as one of the susceptibility genes for temporal lobe epilepsy (TLE). Previous studies indicate that ApoE ɛ4 is associated with several disease-related traits including the increased risk of late posttraumatic seizures, earlier onset of TLE, refractory complex partial seizures, and postictal confusion. Contradictory data were also reported regarding the association between ApoE polymorphisms and TLE. The present study was designed to investigate whether ApoE ɛ4 is a risk factor for TLE and the above clinical variables, as well as to determine whether -491A/T polymorphism may independently alter the risk for TLE in a Chinese Han population. The ApoE and -491A/T polymorphisms were genotyped in 558 controls and 735 patients including 560 TLE patients using polymerase chain reaction-restriction fragment length polymorphism. A significant association was detected between prior trauma and the ApoE ɛ4 allele in TLE patients. However, no significant differences were observed in the genotype and haplotype distributions and allele frequencies of these two polymorphisms between cases and controls. Furthermore, there were no significant associations between these two polymorphisms and the other clinical variables examined. The study illustrates that the ApoE ɛ4 allele may be involved in the development of TLE in those patients with prior trauma in the Chinese Han population.
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Affiliation(s)
- Yuan-Hui Fu
- College of Life Sciences & Bioengineering, Beijing Jiaotong University, 3 Shangyuan Residence, Haidian District, Beijing 100044, PR China
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Cervantes S, Samaranch L, Vidal-Taboada JM, Lamet I, Bullido MJ, Frank-García A, Coria F, Lleó A, Clarimón J, Lorenzo E, Alonso E, Sánchez-Juan P, Rodríguez-Rodríguez E, Combarros O, Rosich M, Vilella E, Pastor P. Genetic variation in APOE cluster region and Alzheimer's disease risk. Neurobiol Aging 2011; 32:2107.e7-17. [PMID: 21752496 DOI: 10.1016/j.neurobiolaging.2011.05.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 05/10/2011] [Accepted: 05/30/2011] [Indexed: 11/29/2022]
Abstract
We report the fine mapping/sequencing results of promoter and regulatory regions of APOE cluster genes (APOE, APOC1, APOC4, APOC2, and TOMM40) in Alzheimer's disease (AD) risk as well as in the progression from mild cognitive impairment (MCI) to AD. Long-range sequencing in 29 MCI subjects who progressed to dementia revealed 7 novel variants. Two potentially relevant novel variants and 34 single nucleotide polymorphisms (SNPs) were genotyped in a large sample of AD, MCI, and control subjects (n = 1453). Globally, very little association signal was observed in our sample in the absence of APOE ε4. Rs5158 (APOC4 intron 1) and rs10413089 (3' to APOC2) showed a trend toward an increase in AD risk independently from APOE ε4 associated risk though it did not survive multiple test correction (uncorrected p = 0.0099 and 0.01, respectively). Interestingly, rs10413089 showed a similar effect in an independent series. The analysis of the discovery sample showed an association of TOMM40 single nucleotide polymorphisms with progression from MCI stage to AD (rs59007384 and rs11556510), as well as with a shorter time to progression from MCI status to AD (rs10119), though these results could not be replicated in independent series. Further studies are needed to investigate the role of APOE cluster variants in AD risk.
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Affiliation(s)
- Sebastián Cervantes
- Neurogenetics Laboratory, Division of Neurosciences, Center for Applied Medical Research, University of Navarra, Pamplona, Spain
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Ertekin-Taner N. Gene expression endophenotypes: a novel approach for gene discovery in Alzheimer's disease. Mol Neurodegener 2011; 6:31. [PMID: 21569597 PMCID: PMC3113300 DOI: 10.1186/1750-1326-6-31] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Accepted: 05/14/2011] [Indexed: 11/15/2022] Open
Abstract
Uncovering the underlying genetic component of any disease is key to the understanding of its pathophysiology and may open new avenues for development of therapeutic strategies and biomarkers. In the past several years, there has been an explosion of genome-wide association studies (GWAS) resulting in the discovery of novel candidate genes conferring risk for complex diseases, including neurodegenerative diseases. Despite this success, there still remains a substantial genetic component for many complex traits and conditions that is unexplained by the GWAS findings. Additionally, in many cases, the mechanism of action of the newly discovered disease risk variants is not inherently obvious. Furthermore, a genetic region with multiple genes may be identified via GWAS, making it difficult to discern the true disease risk gene. Several alternative approaches are proposed to overcome these potential shortcomings of GWAS, including the use of quantitative, biologically relevant phenotypes. Gene expression levels represent an important class of endophenotypes. Genetic linkage and association studies that utilize gene expression levels as endophenotypes determined that the expression levels of many genes are under genetic influence. This led to the postulate that there may exist many genetic variants that confer disease risk via modifying gene expression levels. Results from the handful of genetic studies which assess gene expression level endophenotypes in conjunction with disease risk suggest that this combined phenotype approach may both increase the power for gene discovery and lead to an enhanced understanding of their mode of action. This review summarizes the evidence in support of gene expression levels as promising endophenotypes in the discovery and characterization of novel candidate genes for complex diseases, which may also represent a novel approach in the genetic studies of Alzheimer's and other neurodegenerative diseases.
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Affiliation(s)
- Nilüfer Ertekin-Taner
- Mayo Clinic Florida, Departments of Neurology and Neuroscience, 4500 San Pablo Road, Birdsall 210, Jacksonville, Florida 32224 USA.
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38
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Li S, Zhang H, Gao P, Chen Z, Wang C, Li J. A functional mutation at position -155 in porcine APOE promoter affects gene expression. BMC Genet 2011; 12:40. [PMID: 21549015 PMCID: PMC3098798 DOI: 10.1186/1471-2156-12-40] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Accepted: 05/09/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Apolipoprotein E, a component of the plasma lipoproteins, plays an important role in the transport and metabolism of cholesterol and other lipids. Three single nucleotide polymorphisms (SNPs) -491A>T, -219T>G and +113G>C in the regulatory region of human apolipoprotein E gene (APOE) change the promoter activity and are associated with a wide variety of disorders including Alzheimer disease (AD). Functional SNPs in porcine APOE gene 5' regulatory region have not been explored. RESULTS We examined SNPs within this region (from -831 to +855), and the analysis revealed that the T>A SNP at position -155 among these three polymorphism sites (-440, -155, +501) was found to exert a marked influence on the transcription of the porcine APOE gene. Electrophoretic mobility shift assays showed that the binding affinity of oligonucletides containing the -155A to transcription factor(s) was stronger than that of the -155T. Transient transfection assays and quantitative real-time PCR results revealed that the -155T>A variant enhanced the activity of the APOE promoter and was associated with increased APOE mRNA levels in vivo. CONCLUSIONS These data suggest that the -155T>A mutation in the promoter region of the porcine APOE gene is an important functional variant. The results provided new insights into aspects of pig genetics and might also facilitate the application of pigs in biomedical studies addressing important human diseases.
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Affiliation(s)
- Shixin Li
- Guangdong Provincial Key Lab of Agroanimal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, PR China
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Wu H, Ruan J, Zhang X, Xia H, Jiang Y, Sun X. Association of promoter polymorphism of apolipoprotein E gene with cerebral vasospasm after spontaneous SAH. Brain Res 2010; 1362:112-6. [DOI: 10.1016/j.brainres.2010.09.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 09/03/2010] [Accepted: 09/03/2010] [Indexed: 11/19/2022]
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Vargas T, Bullido MJ, Martinez-Garcia A, Antequera D, Clarimon J, Rosich-Estrago M, Martin-Requero A, Mateo I, Rodriguez-Rodriguez E, Vilella-Cuadrada E, Frank A, Lleo A, Molina-Porcel L, Blesa R, Combarros O, Gomez-Isla T, Bermejo-Pareja F, Valdivieso F, Carro E. A megalin polymorphism associated with promoter activity and Alzheimer's disease risk. Am J Med Genet B Neuropsychiatr Genet 2010; 153B:895-902. [PMID: 20052685 DOI: 10.1002/ajmg.b.31056] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Elevated cerebral levels of amyloid beta-protein (Abeta) occur in Alzheimer's disease (AD), yet only a few patients show evidence of increased Abeta production. This observation suggests that many, perhaps most, cases of AD are caused by faulty clearance of Abeta. Megalin, which plays an important role in mediating Abeta clearance, is an attractive candidate gene for genetic association with AD. To investigate this hypothesis, we analyzed the megalin gene in a population of 2,183 subjects. Genetic analysis indicated that the rs3755166 (G/A) polymorphism located in the megalin promoter associated with risk for AD, dependently of apolipoprotein E genotype. The rs3755166 AA genotype frequency was significantly greater in AD patients than in control subjects. Furthermore, the luciferase reporter assay indicated that the rs3755166 A variant has 20% less transcriptional activity than the rs3755166 G variant. This study provides strong evidence that this megalin polymorphism confers a greater risk for AD, and supports a biological role for megalin in the neurodegenerative processes involved in AD.
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Affiliation(s)
- Teo Vargas
- Neuroscience Laboratory, Research Center, Hospital 12 de Octubre, Madrid, Spain
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Bekris LM, Galloway NM, Montine TJ, Schellenberg GD, Yu CE. APOE mRNA and protein expression in postmortem brain are modulated by an extended haplotype structure. Am J Med Genet B Neuropsychiatr Genet 2010; 153B:409-417. [PMID: 19554612 PMCID: PMC2829359 DOI: 10.1002/ajmg.b.30993] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Currently the epsilon4 allele of the apolipoprotein E gene (APOE) is the strongest genetic risk factor for late onset Alzheimer's disease (AD). However, inheritance of the APOE epsilon4 allele is not necessary or sufficient for the development of AD. Genetic evidence suggests that multiple loci in a 70 kb region surrounding APOE are associated with AD risk. Even though these loci could represent surrogate markers in linkage disequilibrium with APOE epsilon4 allele, they could also contribute biological effects independent of the APOE epsilon4 allele. Our previous study identified multiple SNPs upstream from APOE that are associated with cerebrospinal fluid apoE levels, suggesting that a haplotype structure proximal to APOE can influence apoE expression. In this study, we examined apoE expression in human post-mortem brain (PMB), and constructed chromosome-phase-separated haplotypes of the APOE proximal region to evaluate their effect on PMB apoE expression. ApoE protein expression was found to differ among AD brain regions and to differ between AD and control hippocampus. In addition, an extended APOE proximal haplotype structure, spanning from the TOMM40 gene to the APOE promoter, may modulate apoE expression in a brain region-specific manner and may influence AD disease status. In conclusion, this haplotype-phenotype analysis of apoE expression in PMB suggests that either; (1) the cis-regulation of APOE expression levels extends far upstream of the APOE promoter or (2) an APOE epsilon4 allele independent mechanism involving the TOMM40 gene plays a role in the risk of AD.
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Affiliation(s)
- Lynn M. Bekris
- Geriatric Research, Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, Washington,Department of Medicine, University of Washington, Seattle, Washington
| | - Nichole M. Galloway
- Geriatric Research, Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, Washington
| | - Thomas J. Montine
- Department of Pathology, University of Washington, Seattle, Washington
| | - Gerard D. Schellenberg
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Chang-En Yu
- Geriatric Research, Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, Washington,Department of Medicine, University of Washington, Seattle, Washington
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Valenza A, Bizzarro A, Marra C, Lauria A, Guglielmi V, Rossi C, Tiziano FD, Brahe C, Masullo C. The APOE-491 A/T promoter polymorphism effect on cognitive profile of Alzheimer's patients. Neurosci Lett 2010; 472:199-203. [PMID: 20152880 DOI: 10.1016/j.neulet.2010.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 01/25/2010] [Accepted: 02/02/2010] [Indexed: 11/21/2022]
Abstract
Alzheimer's Disease (AD) is a neurodegenerative disorder with a complex aetiology displayed by multiple pathogenic factors. The APOE varepsilon4 allele represents the only established genetic risk factor for sporadic AD; in addition, previous findings on three single nucleotide polymorphisms (SNPs) located on the APOE promoter region, have led to a growing interest in their potential role in AD pathogenesis. The -491 A/T promoter polymorphism has been the one most frequently shown to be associated with AD, as it influences the APOE coding region transcription. The aim of this study was to evaluate the possible effect of the -491 A/T polymorphism on the cognitive profile of sporadic AD patients with a disease severity ranging from mild to moderate. Our results showed that patients carrying the -491 AA genotype had poorer cognitive performances than the -491 AT ones, statistically significant in demanding tests of visual attention, especially for the late-onset AD (LOAD). No further differences on cognitive profile were observed when stratifying AA and AT patients according to their APOE genotype. These results suggest a possible functional effect of the -491 A/T promoter on the neuropsychological performances of AD. This role seems to be independent of APOE genotype. In fact the effect of -491 A/T occurs predominantly on attention while the APOE varepsilon4 allele mainly affects memory performances. According to the biological effect exerted on APOE transcription, the -491 A/T polymorphism could be considered a disease modifier more than a risk factor for sporadic AD.
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Maloney B, Ge YW, Petersen RC, Hardy J, Rogers JT, Pérez-Tur J, Lahiri DK. Functional characterization of three single-nucleotide polymorphisms present in the human APOE promoter sequence: Differential effects in neuronal cells and on DNA-protein interactions. Am J Med Genet B Neuropsychiatr Genet 2010; 153B:185-201. [PMID: 19504470 PMCID: PMC5875733 DOI: 10.1002/ajmg.b.30973] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Variations in levels of apolipoprotein E (ApoE) have been tied to the risk and progression of Alzheimer's disease (AD). Our group has previously compared and contrasted the promoters of the mouse and human ApoE gene (APOE) promoter sequences and found notable similarities and significant differences that suggest the importance of the APOE promoter's role in the human disease. We examine here three specific single-nucleotide polymorphisms within the human APOE promoter region, specifically at -491 (A/T), -427 (T/C), and at -219 (G/T) upstream from the +1 transcription start site. The -219 and -491 polymorphic variations have significant association with instance of AD, and -491AA has significant risk even when stratified for the APOEepsilon4 allele. We also show significant effects on reporter gene expression in neuronal cell cultures, and, notably, these effects are modified by species origin of the cells. The -491 and -219 polymorphisms may have an interactive effect in addition to any independent activity. DNA-protein interactions differ between each polymorphic state. We propose SP1 and GATA as candidates for regulatory control of the -491 and -219 polymorphic sites. This work's significance lies in drawing connection among APOE promoter polymorphisms' associations with AD to functional promoter activity differences and specific changes in DNA-protein interactions in cell culture-based assays. Taken together, these results suggest that APOE expression levels are a risk factor for AD irrespective of APOEepsilon4 allele status.
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Affiliation(s)
- Bryan Maloney
- Department of Psychiatry, Institute of Psychiatric Research, Laboratory of Molecular Neurogenetics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Yuan-Wen Ge
- Department of Psychiatry, Institute of Psychiatric Research, Laboratory of Molecular Neurogenetics, Indiana University School of Medicine, Indianapolis, Indiana
| | | | - John Hardy
- Department of Molecular Neuroscience and Reta Lila Weston Laboratories, Institute of Neurology, UCL, Queen Square, London, UK
| | - Jack T. Rogers
- Department of Psychiatry, MGH, Harvard Medical School, Charlestown, Massachusetts
| | - Jordi Pérez-Tur
- Unitat de Genètica Molecular and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Institut de Biomedicina de València-CSIC, València, Spain
| | - Debomoy K. Lahiri
- Department of Psychiatry, Institute of Psychiatric Research, Laboratory of Molecular Neurogenetics, Indiana University School of Medicine, Indianapolis, Indiana,Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana,Correspondence to: Dr. Debomoy K. Lahiri, Department of Psychiatry, Institute of Psychiatric, Research, Indiana University School of Medicine, 791 Union Drive, Indianapolis, IN 46202.
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Maloney B, Ray B, Hayden EP, Nurnberger JI Jr, Lahiri DK. Development and validation of the high-quality 'rapid method for swab' to genotype the HTTLPR serotonin transporter (SLC6A4) promoter polymorphism. Psychiatr Genet 2009; 19:72-82. [PMID: 19668112 DOI: 10.1097/YPG.0b013e3283208091] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The importance of genetic variation to the etiology of neuropsychiatric disorders is well established and is currently being examined for diagnosis and treatment. The most popular method of obtaining material for genotype analysis, high-yielding DNA extraction from blood, has several limitations, including invasiveness, need for skilled individuals to collect material, and requirement for cold storage. Saliva sampling is noninvasive and trained personnel are less necessary, but it still requires a relatively high level of subject compliance. Buccal mucosa cells sampling is almost completely noninvasive, reducing compliance issues significantly. Samples collected have been shown to produce usable DNA after shipment through conventional mail. The DNA produced by rapid elution of these swabs in chaotropic buffers is, however, of limited quality and low purity. OBJECTIVE Our aim was to develop a rapid, economical, and environmentally safe method for extraction of high-quality genomic DNA, which can be used to determine clinically important genotypes from trace quantity samples and which has sufficient yield for multiple assays. METHODS We developed a method of extracting high-quality genomic DNA from buccal swab, which we termed the 'rapid method for swab' (RMS). We compared RMS with two established procedures, specifically the original rapid method and the commercially available Buccal Amp method. We assessed the generated genomic DNAs by their (i) quality, (ii) quantity, (iii) restriction enzyme digestibility, and (iv) PCR-based genotyping in addition to time, cost, and environmental impact of the procedures. MAIN RESULTS DNA generated by RMS was of higher purity than that by Buccal Amp. RMS is nonenzymatic and does not use strong chaotropic salts or extreme pH. We also showed the suitability of RMS-DNA for LA/LG genotyping as generated by PCR using 7-deaza-dGTP. CONCLUSION The RMS procedure is novel, efficient, safe, and yields sufficient material for multiple genotyping analyses. The RMS produces DNA of high quality from a single human buccal swab. RMS is a noninvasive technique and particularly suitable for children and older individuals and in field collection settings.
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Fritsche LG, Freitag-Wolf S, Bettecken T, Meitinger T, Keilhauer CN, Krawczak M, Weber BHF. Age-related macular degeneration and functional promoter and coding variants of the apolipoprotein E gene. Hum Mutat 2009; 30:1048-53. [PMID: 19384966 DOI: 10.1002/humu.20957] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Age-related macular degeneration (AMD) is a frequent, multifactorial disease of the central retina and a major cause of irreversible vision loss in industrialized countries. Apolipoprotein E (APOE) has been consistently associated with AMD, particularly its two functional isoforms E2 (predisposing) and E4 (protective). The biological correlate of this association, however, is still unclear. In this study, we have defined an extended haplotype block encompassing the entire APOE gene locus, including known coding as well as cis-regulatory promoter variants. Of the five extended APOE haplotypes common in the general population, two were found to be significantly associated with AMD, namely G-G-G-G-epsilon2 (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.19-2.12) and T-G-A-G-epsilon4 (OR, 0.76; 95% CI, 0.58-0.99). When analyzing common extended haplotype combinations, T-C-G-G-epsilon3/T-G-A-G-epsilon4 exhibited the most prominent effect (OR, 0.32; 95% CI, 0.20-0.51). Intriguingly, we also found one extended epsilon3-haplotype, G-G-G-A-epsilon3, to be protective in the homozygous state (OR, 0.65; 95% CI, 0.49-0.87). Since single nucleotide polymorphism (SNP) rs405509:G>T is a constituent of the extended epsilon-haplotype block and is known to significantly influence APOE promoter activity, we hypothesize that both the relative rate of APOE isoform expression in conjunction with established functional differences of the respective isoforms may be crucial in mediating AMD pathology. This would also imply that genotyping of the core epsilon-haplotypes alone is not sufficient to estimate AMD risk, but that determination of extended haplotype combinations, including the functional promoter SNP rs405509, is required instead.
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Affiliation(s)
- Lars G Fritsche
- Institute of Human Genetics, University of Regensburg, Regensburg, Germany
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Hiekkanen H, Kurki T, Brandstack N, Kairisto V, Tenovuo O. MRI changes and ApoE genotype, a prospective 1-year follow-up of traumatic brain injury: A pilot study. Brain Inj 2009; 21:1307-14. [DOI: 10.1080/02699050701739549] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Carrillo MC, Blackwell A, Hampel H, Lindborg J, Sperling R, Schenk D, Sevigny JJ, Ferris S, Bennett DA, Craft S, Hsu T, Klunk W. Early risk assessment for Alzheimer's disease. Alzheimers Dement 2009; 5:182-96. [PMID: 19328456 DOI: 10.1016/j.jalz.2009.01.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Accepted: 01/14/2009] [Indexed: 12/29/2022]
Abstract
The purpose of the Alzheimer's Association Research Roundtable meeting was to discuss the potential of finding diagnostic tools to determine the earliest risk factors for Alzheimer's disease (AD). Currently, drugs approved for AD address symptoms which are generally manifest after the disease is already well-established, but there is a growing pipeline of drugs that may alter the underlying pathology and therefore slow or halt progression of the disease. As these drugs become available, it will become increasingly imperative that those at risk for AD be detected and possibly treated early, especially given recent indications that the disease process may start decades before the first clinical symptoms are recognized. Early detection must go hand-in-hand with qualified tools to determine the efficacy of drugs in people who may be asymptomatic or who have only very mild symptoms of the disease. Devising strategies and screening tools to identify and monitor those at risk in order to perform "prevention" trials is seen by many as a top public-health priority, made all the more urgent by an impending growth in the elderly population worldwide.
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Trebuňová M, Slabá E, Habalová V, Gdovinová Z. The role of the −427T/C apolipoprotein E promoter polymorphism in the pathogenesis of Alzheimer’s disease, vascular dementia and mixed dementia. J Neural Transm (Vienna) 2009; 116:339-44. [DOI: 10.1007/s00702-008-0178-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Accepted: 12/17/2008] [Indexed: 11/26/2022]
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Bekris LM, Millard SP, Galloway NM, Vuletic S, Albers JJ, Li G, Galasko DR, DeCarli C, Farlow MR, Clark CM, Quinn JF, Kaye JA, Schellenberg GD, Tsuang D, Peskind ER, Yu CE. Multiple SNPs within and surrounding the apolipoprotein E gene influence cerebrospinal fluid apolipoprotein E protein levels. J Alzheimers Dis 2008; 13:255-66. [PMID: 18430993 DOI: 10.3233/jad-2008-13303] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The epsilon4 allele of the apolipoprotein E gene (APOE) is associated with increased risk and earlier age at onset in late onset Alzheimer's disease (AD). Other factors, such as expression level of apolipoprotein E protein (apoE), have been postulated to modify the APOE related risk of developing AD. Multiple loci in and outside of APOE are associated with a high risk of AD. The aim of this exploratory hypothesis generating investigation was to determine if some of these loci predict cerebrospinal fluid (CSF) apoE levels in healthy non-demented subjects. CSF apoE levels were measured from healthy non-demented subjects 21-87 years of age (n=134). Backward regression models were used to evaluate the influence of 21 SNPs, within and surrounding APOE, on CSF apoE levels while taking into account age, gender, APOE epsilon4 and correlation between SNPs (linkage disequilibrium). APOE epsilon4 genotype does not predict CSF apoE levels. Three SNPs within the TOMM40 gene, one APOE promoter SNP and two SNPs within distal APOE enhancer elements (ME1 and BCR) predict CSF apoE levels. Further investigation of the genetic influence of these loci on apoE expression levels in the central nervous system is likely to provide new insight into apoE regulation as well as AD pathogenesis.
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Affiliation(s)
- Lynn M Bekris
- Geriatric Research, Education, and Clinical Center (GRECC), VA Puget Sound Health Care System, Seattle, WA 98108, USA.
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Bahia VS, Kok F, Marie SN, Shinjo SO, Caramelli P, Nitrini R. Polymorphisms of APOE and LRP genes in Brazilian individuals with Alzheimer disease. Alzheimer Dis Assoc Disord 2008; 22:61-5. [PMID: 18317248 DOI: 10.1097/WAD.0b013e31815a9da7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Alzheimer disease (AD) is the most frequent cause of dementia in Western countries. Putative genetic risk factors for AD are polymorphisms in the apolipoprotein E (APOE) gene and in the low-density lipoprotein receptor-related protein (LRP) gene. Our objective was to investigate the role of the APOE coding region polymorphisms epsilon 2, epsilon 3, and epsilon 4 and APOE promoter variants A/T at position -491 and G/T at -219, as well as LRP polymorphism C/T, as risk factors for AD in Brazilian individuals. One hundred and twenty patients with probable AD, along with 120 controls were analyzed. A significant difference between patients and controls for epsilon 4 alleles was observed: frequency of this allele in AD was 0.31, and 0.10 in controls. Individuals with 2 epsilon 4 alleles had a higher risk for AD than subjects with only 1 such allele; presence of 1 epsilon 2 allele proved protective. The presence of the T allele of the -219 polymorphism was also associated with an increased risk of AD, but this polymorphism is in linkage disequilibrium with APOE epsilon polymorphisms. No significant differences between patients and controls were observed for -491 APOE or LRP polymorphisms. In this Brazilian population, both the epsilon 4 allele and T -219 polymorphism were associated with an increased risk for AD.
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