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1.
Nat Genet ; 51(11): 1624-1636, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31636452

RESUMO

Subcortical brain structures are integral to motion, consciousness, emotions and learning. We identified common genetic variation related to the volumes of the nucleus accumbens, amygdala, brainstem, caudate nucleus, globus pallidus, putamen and thalamus, using genome-wide association analyses in almost 40,000 individuals from CHARGE, ENIGMA and UK Biobank. We show that variability in subcortical volumes is heritable, and identify 48 significantly associated loci (40 novel at the time of analysis). Annotation of these loci by utilizing gene expression, methylation and neuropathological data identified 199 genes putatively implicated in neurodevelopment, synaptic signaling, axonal transport, apoptosis, inflammation/infection and susceptibility to neurological disorders. This set of genes is significantly enriched for Drosophila orthologs associated with neurodevelopmental phenotypes, suggesting evolutionarily conserved mechanisms. Our findings uncover novel biology and potential drug targets underlying brain development and disease.

2.
Aging Cell ; 18(4): e12964, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31144443

RESUMO

CpG-related single nucleotide polymorphisms (CGS) have the potential to perturb DNA methylation; however, their effects on Alzheimer disease (AD) risk have not been evaluated systematically. We conducted a genome-wide association study using a sliding-window approach to measure the combined effects of CGSes on AD risk in a discovery sample of 24 European ancestry cohorts (12,181 cases, 12,601 controls) from the Alzheimer's Disease Genetics Consortium (ADGC) and replication sample of seven European ancestry cohorts (7,554 cases, 27,382 controls) from the International Genomics of Alzheimer's Project (IGAP). The potential functional relevance of significant associations was evaluated by analysis of methylation and expression levels in brain tissue of the Religious Orders Study and the Rush Memory and Aging Project (ROSMAP), and in whole blood of Framingham Heart Study participants (FHS). Genome-wide significant (p < 5 × 10-8 ) associations were identified with 171 1.0 kb-length windows spanning 932 kb in the APOE region (top p < 2.2 × 10-308 ), five windows at BIN1 (top p = 1.3 × 10-13 ), two windows at MS4A6A (top p = 2.7 × 10-10 ), two windows near MS4A4A (top p = 6.4 × 10-10 ), and one window at PICALM (p = 6.3 × 10-9 ). The total number of CGS-derived CpG dinucleotides in the window near MS4A4A was associated with AD risk (p = 2.67 × 10-10 ), brain DNA methylation (p = 2.15 × 10-10 ), and gene expression in brain (p = 0.03) and blood (p = 2.53 × 10-4 ). Pathway analysis of the genes responsive to changes in the methylation quantitative trait locus signal at MS4A4A (cg14750746) showed an enrichment of methyltransferase functions. We confirm the importance of CGS in AD and the potential for creating a functional CpG dosage-derived genetic score to predict AD risk.

3.
J Alzheimers Dis ; 68(3): 1161-1170, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30883345

RESUMO

BACKGROUND: The UNC5C rs3846455G allele has been linked to poor cognitive resilience against age-related neuropathologies, but this association remains to be replicated, and the allele's effect on hippocampal neurodegeneration needs to be examined. OBJECTIVE: To further validate the association between rs3846455G and faster cognitive decline, especially among cognitively normal older adults, and to assess whether rs3846455G predicts accelerated hippocampal volume loss in older adults. METHODS: We assessed participants in the Harvard Aging Brain Study (HABS), a longitudinal cohort study of older adults who were clinically normal at baseline. To avoid bias from population admixture, analyses were limited to participants of European descent with longitudinal neuroimaging data (n = 174). Linear mixed effect models were used to examine the effect of rs3846455G on longitudinal change of the Preclinical Alzheimer Cognitive Composite (PACC) and MRI-measured bilateral hippocampal volume, adjusting for baseline amyloid-ß (Aß) measured by the cortical Pittsburgh Compound B PET distributed volume ratio. We also tested whether hippocampal atrophy mediates the association between rs3846455G and greater PACC decline through a mediation analysis. RESULTS: rs3846455G was associated with greater PACC decline (ß= -0.087/year, 95% CI -0.169 to -0.005, p = 0.039) after controlling for baseline Aß. Further, rs3846455G predicted accelerated hippocampal atrophy after controlling for baseline Aß (ß= -57.3 mm3/year, 95% CI -102.8 to -11.9, p = 0.014). The association between rs3846455G and greater PACC decline was partially mediated by accelerated hippocampal atrophy (mediated effect (relative scale) = -0.014, 95% CI -0.032 to -6.0×10-4, p = 0.039). CONCLUSION: UNC5C rs3846455G predicts greater cognitive decline and accelerated hippocampal atrophy in clinically normal older adults.

4.
Nat Commun ; 9(1): 3930, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30258103

RESUMO

Social networks are conduits of support, information, and health behavior flows. Existing measures of social networks used in clinical research are typically summative scales of social support or artificially truncated networks of ≤ 5 people. Here, we introduce a quantitative social network assessment tool on a secure open-source web platform, readily deployable in large-scale clinical studies. The tool maps an individual's personal network, including specific persons, their relationships to each other, and their health habits. To demonstrate utility, we used the tool to measure the social networks of 1493 persons at risk of multiple sclerosis. We examined each person's social network in relation to self-reported neurological disability. We found that the characteristics of persons surrounding the participant, such as negative health behaviors, were strongly associated with the individual's functional disability. This quantitative assessment reveals the key elements of individuals' social environments that could be targeted in clinical trials.

5.
Sci Data ; 5: 180142, 2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30084846

RESUMO

We initiated the systematic profiling of the dorsolateral prefrontal cortex obtained from a subset of autopsied individuals enrolled in the Religious Orders Study (ROS) or the Rush Memory and Aging Project (MAP), which are jointly designed prospective studies of aging and dementia with detailed, longitudinal cognitive phenotyping during life and a quantitative, structured neuropathologic examination after death. They include over 3,322 subjects. Here, we outline the first generation of data including genome-wide genotypes (n=2,090), whole genome sequencing (n=1,179), DNA methylation (n=740), chromatin immunoprecipitation with sequencing using an anti-Histone 3 Lysine 9 acetylation (H3K9Ac) antibody (n=712), RNA sequencing (n=638), and miRNA profile (n=702). Generation of other omic data including ATACseq, proteomic and metabolomics profiles is ongoing. Thanks to its prospective design and recruitment of older, non-demented individuals, these data can be repurposed to investigate a large number of syndromic and quantitative neuroscience phenotypes. The many subjects that are cognitively non-impaired at death also offer insights into the biology of the human brain in older non-impaired individuals.

6.
Lancet Neurol ; 17(9): 773-781, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30093249

RESUMO

BACKGROUND: Transactive response DNA-binding protein of 43 kDa (TDP-43) proteinopathy in older adults frequently coexists with Alzheimer's disease pathology and hippocampal sclerosis. It is unclear whether there is a link between APOE ε4 and TDP-43 proteinopathy, and the role of APOE ε4 in the association of TDP-43 proteinopathy with hippocampal sclerosis remains to be examined. We investigated the relationships of TDP-43 proteinopathy and hippocampal sclerosis with APOE ε4. METHODS: We used data from two community-based cohort studies of ageing and dementia: the Religious Orders Study (ROS) and the Rush Memory and Aging Project (MAP). A battery of cognitive tests examining multiple cognitive domains is given to ROS-MAP participants each year, and a measure of annual global cognitive function for each participant is derived by averaging Z scores of these tests. The final clinical diagnosis is assigned after death by a neurologist using all available clinical data without access to post-mortem pathology. Amyloid-ß, paired helical filament tau, Lewy bodies, TDP-43, and hippocampal sclerosis were microscopically evaluated in the midbrain, medial temporal, and neocortical regions that capture the progression of each neuropathology. TDP-43 proteinopathy topographic stage was recorded as an ordinal variable, and TDP-43 burden was defined by averaging a semi-quantitative six-point scale across six brain regions. The relationships among APOE ε4, TDP-43 proteinopathy, and hippocampal sclerosis were tested with regression models controlled for sex and age at death, and they were further explored with a mediation analysis using the quasi-Bayesian Monte Carlo method. FINDINGS: ROS began data collection in 1994, and MAP began data collection in 1997. The data included in this study were analysed from Jan 16, 2017, to July 12, 2017. When analysis began in January, 2017, a total of 1059 ROS-MAP participants who were deceased had APOE genotype and complete pathological measures for amyloid-ß, paired helical filament tau, and TDP-43 proteinopathy stage. After excluding 15 participants with other pathological diagnoses, 1044 participants, 1042 of whom also had measures of Lewy body pathology, were included in this study (470 from ROS and 574 from MAP). APOE ε4 count was associated with higher TDP-43 proteinopathy stage (odds ratio [OR] 2·0, 95% CI 1·6-2·6; p=1·9 × 10-9) and TDP-43 burden (0·40, 0·28-0·52; p=1·2 × 10-10). Amyloid-ß, paired helical filament tau, or Lewy body pathology did not fully explain this association. APOE ε4 increased the odds of hippocampal sclerosis (OR 2·1, 95% CI 1·4-3·0; p=1·7 × 10-4); this effect was largely mediated by TDP-43 burden (mediated effect p<1·0 × 10-4) but not directly by APOE ε4 (direct effect p=0·40). APOE ε4 was associated with worse global cognition proximate to death even after adjusting for amyloid-ß and paired helical filament tau (estimated effect -0·18, 95% CI -0·31 to -0·04; p=0·010), but this association was attenuated by additionally adjusting for TDP-43 burden (-0·09, -0·22 to 0·04; p=0·18). INTERPRETATION: APOE ε4 seems to increase TDP-43 burden, and this effect in turn was associated with higher odds of hippocampal sclerosis, a pathology potentially downstream of TDP-43 proteinopathy. TDP-43 proteinopathy contributes to the detrimental effect of APOE ε4 on late-life cognition through mechanisms independent of Alzheimer's disease pathology, and future research should consider that TDP-43 proteinopathy might be an integral component of APOE-related neurodegeneration. FUNDING: US National Institute on Aging and Alzheimer's Association.

7.
Nat Neurosci ; 21(6): 811-819, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29802388

RESUMO

There is a need for new therapeutic targets with which to prevent Alzheimer's disease (AD), a major contributor to aging-related cognitive decline. Here we report the construction and validation of a molecular network of the aging human frontal cortex. Using RNA sequence data from 478 individuals, we first build a molecular network using modules of coexpressed genes and then relate these modules to AD and its neuropathologic and cognitive endophenotypes. We confirm these associations in two independent AD datasets. We also illustrate the use of the network in prioritizing amyloid- and cognition-associated genes for in vitro validation in human neurons and astrocytes. These analyses based on unique cohorts enable us to resolve the role of distinct cortical modules that have a direct effect on the accumulation of AD pathology from those that have a direct effect on cognitive decline, exemplifying a network approach to complex diseases.

8.
Genetics ; 209(1): 51-64, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29507048

RESUMO

Recent technical and methodological advances have greatly enhanced genome-wide association studies (GWAS). The advent of low-cost, whole-genome sequencing facilitates high-resolution variant identification, and the development of linear mixed models (LMM) allows improved identification of putatively causal variants. While essential for correcting false positive associations due to sample relatedness and population stratification, LMMs have commonly been restricted to quantitative variables. However, phenotypic traits in association studies are often categorical, coded as binary case-control or ordered variables describing disease stages. To address these issues, we have devised a method for genomic association studies that implements a generalized LMM (GLMM) in a Bayesian framework, called Bayes-GLMM Bayes-GLMM has four major features: (1) support of categorical, binary, and quantitative variables; (2) cohesive integration of previous GWAS results for related traits; (3) correction for sample relatedness by mixed modeling; and (4) model estimation by both Markov chain Monte Carlo sampling and maximal likelihood estimation. We applied Bayes-GLMM to the whole-genome sequencing cohort of the Alzheimer's Disease Sequencing Project. This study contains 570 individuals from 111 families, each with Alzheimer's disease diagnosed at one of four confidence levels. Using Bayes-GLMM we identified four variants in three loci significantly associated with Alzheimer's disease. Two variants, rs140233081 and rs149372995, lie between PRKAR1B and PDGFA The coded proteins are localized to the glial-vascular unit, and PDGFA transcript levels are associated with Alzheimer's disease-related neuropathology. In summary, this work provides implementation of a flexible, generalized mixed-model approach in a Bayesian framework for association studies.


Assuntos
Doença de Alzheimer/genética , Teorema de Bayes , Predisposição Genética para Doença , Modelos Lineares , Locos de Características Quantitativas , Idade de Início , Algoritmos , Animais , Estudo de Associação Genômica Ampla , Humanos , Cadeias de Markov , Camundongos , Modelos Biológicos , Método de Monte Carlo , Sequenciamento Completo do Genoma
9.
Nat Commun ; 9(1): 539, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29416036

RESUMO

With a rapidly aging global human population, finding a cure for late onset neurodegenerative diseases has become an urgent enterprise. However, these efforts are hindered by the lack of understanding of what constitutes the phenotype of aged human microglia-the cell type that has been strongly implicated by genetic studies in the pathogenesis of age-related neurodegenerative disease. Here, we establish the set of genes that is preferentially expressed by microglia in the aged human brain. This HuMi_Aged gene set captures a unique phenotype, which we confirm at the protein level. Furthermore, we find this gene set to be enriched in susceptibility genes for Alzheimer's disease and multiple sclerosis, to be increased with advancing age, and to be reduced by the protective APOEε2 haplotype. APOEε4 has no effect. These findings confirm the existence of an aging-related microglial phenotype in the aged human brain and its involvement in the pathological processes associated with brain aging.

10.
Sci Transl Med ; 9(421)2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29263232

RESUMO

Microglia are emerging as a key cell type in neurodegenerative diseases, yet human microglia are challenging to study in vitro. We developed an in vitro cell model system composed of human monocyte-derived microglia-like (MDMi) cells that recapitulated key aspects of microglia phenotype and function. We then used this model system to perform an expression quantitative trait locus (eQTL) study examining 94 genes from loci associated with Alzheimer's disease, Parkinson's disease, and multiple sclerosis. We found six loci (CD33, PILRB, NUP160, LRRK2, RGS1, and METTL21B) in which the risk haplotype drives the association with both disease susceptibility and altered expression of a nearby gene (cis-eQTL). In the PILRB and LRRK2 loci, the cis-eQTL was found in the MDMi cells but not in human peripheral blood monocytes, suggesting that differentiation of monocytes into microglia-like cells led to the acquisition of a cellular state that could reveal the functional consequences of certain genetic variants. We further validated the effect of risk haplotypes at the protein level for PILRB and CD33, and we confirmed that the CD33 risk haplotype altered phagocytosis by the MDMi cells. We propose that increased LRRK2 gene expression by MDMi cells could be a functional outcome of rs76904798, a single-nucleotide polymorphism in the LRKK2 locus that is associated with Parkinson's disease.


Assuntos
Predisposição Genética para Doença , Variação Genética , Microglia/patologia , Modelos Biológicos , Degeneração Neural/genética , Degeneração Neural/patologia , Polaridade Celular , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Monócitos/patologia , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Isoformas de Proteínas/metabolismo , Locos de Características Quantitativas/genética , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo
11.
Nat Neurosci ; 20(10): 1418-1426, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28869584

RESUMO

We report a multi-omic resource generated by applying quantitative trait locus (xQTL) analyses to RNA sequence, DNA methylation and histone acetylation data from the dorsolateral prefrontal cortex of 411 older adults who have all three data types. We identify SNPs significantly associated with gene expression, DNA methylation and histone modification levels. Many of these SNPs influence multiple molecular features, and we demonstrate that SNP effects on RNA expression are fully mediated by epigenetic features in 9% of these loci. Further, we illustrate the utility of our new resource, xQTL Serve, by using it to prioritize the cell type(s) most affected by an xQTL. We also reanalyze published genome wide association studies using an xQTL-weighted analysis approach and identify 18 new schizophrenia and 2 new bipolar susceptibility variants, which is more than double the number of loci that can be discovered with a larger blood-based expression eQTL resource.


Assuntos
Encéfalo/metabolismo , Epigênese Genética/genética , Genoma Humano/genética , Locos de Características Quantitativas/genética , Transcriptoma/genética , Transtorno Bipolar/genética , Epigenômica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/genética
12.
Neurol Genet ; 3(4): e176, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28761931

RESUMO

OBJECTIVE: To determine whether common genetic variants in UNC5C, a recently identified late-onset Alzheimer disease (LOAD) dementia susceptibility gene, are associated with AD susceptibility or AD-related clinical/pathologic phenotypes. METHODS: We used data from deceased individuals of European descent who participated in the Religious Orders Study or the Rush Memory and Aging Project (n = 1,288). We examined whether there were associations between single nucleotide polymorphisms (SNPs) within ±100 kb of the UNC5C gene and a diagnosis of AD dementia, global cognitive decline, a pathologic diagnosis of AD, ß-amyloid load, neuritic plaque count, diffuse plaque count, paired helical filament tau density, neurofibrillary tangle count, and cerebral amyloid angiopathy (CAA) score. We also evaluated the relation of the CAA-associated variant and dorsolateral prefrontal cortex (DLPFC) UNC5C RNA expression. Secondary analyses were performed to examine the interaction of the CAA-associated SNP and known genetic risk factors of CAA as well as the association of the SNP with other cerebrovascular pathologies. RESULTS: A set of UNC5C SNPs tagged by rs28660566T was associated with a higher CAA score (p = 2.3 × 10-6): each additional rs28660566T allele was associated with a 0.60 point higher CAA score, which is equivalent to approximately 75% of the higher CAA score associated with each allele of APOE ε4. rs28660566T was weakly associated with lower UNC5C expression in the human DLPFC (p = 0.036). Moreover, rs28660566T had a synergistic interaction with APOE ε4 on their association with higher CAA severity (p = 0.027) and was associated with more severe arteriolosclerosis (p = 0.0065). CONCLUSIONS: Targeted analysis of the UNC5C region uncovered a set of SNPs associated with CAA.

13.
Nat Genet ; 49(9): 1373-1384, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28714976

RESUMO

We identified rare coding variants associated with Alzheimer's disease in a three-stage case-control study of 85,133 subjects. In stage 1, we genotyped 34,174 samples using a whole-exome microarray. In stage 2, we tested associated variants (P < 1 × 10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, we used an additional 14,997 samples to test the most significant stage 2 associations (P < 5 × 10-8) using imputed genotypes. We observed three new genome-wide significant nonsynonymous variants associated with Alzheimer's disease: a protective variant in PLCG2 (rs72824905: p.Pro522Arg, P = 5.38 × 10-10, odds ratio (OR) = 0.68, minor allele frequency (MAF)cases = 0.0059, MAFcontrols = 0.0093), a risk variant in ABI3 (rs616338: p.Ser209Phe, P = 4.56 × 10-10, OR = 1.43, MAFcases = 0.011, MAFcontrols = 0.008), and a new genome-wide significant variant in TREM2 (rs143332484: p.Arg62His, P = 1.55 × 10-14, OR = 1.67, MAFcases = 0.0143, MAFcontrols = 0.0089), a known susceptibility gene for Alzheimer's disease. These protein-altering changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified risk genes in Alzheimer's disease. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to the development of Alzheimer's disease.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/genética , Imunidade Inata/genética , Glicoproteínas de Membrana/genética , Microglia/metabolismo , Fosfolipase C gama/genética , Polimorfismo de Nucleotídeo Único , Receptores Imunológicos/genética , Sequência de Aminoácidos , Estudos de Casos e Controles , Exoma/genética , Perfilação da Expressão Gênica , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Humanos , Desequilíbrio de Ligação , Razão de Chances , Mapas de Interação de Proteínas/genética , Homologia de Sequência de Aminoácidos
14.
Circulation ; 135(24): 2336-2353, 2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28461624

RESUMO

BACKGROUND: Common diseases such as coronary heart disease (CHD) are complex in etiology. The interaction of genetic susceptibility with lifestyle factors may play a prominent role. However, gene-lifestyle interactions for CHD have been difficult to identify. Here, we investigate interaction of smoking behavior, a potent lifestyle factor, with genotypes that have been shown to associate with CHD risk. METHODS: We analyzed data on 60 919 CHD cases and 80 243 controls from 29 studies for gene-smoking interactions for genetic variants at 45 loci previously reported to be associated with CHD risk. We also studied 5 loci associated with smoking behavior. Study-specific gene-smoking interaction effects were calculated and pooled using fixed-effects meta-analyses. Interaction analyses were declared to be significant at a P value of <1.0×10-3 (Bonferroni correction for 50 tests). RESULTS: We identified novel gene-smoking interaction for a variant upstream of the ADAMTS7 gene. Every T allele of rs7178051 was associated with lower CHD risk by 12% in never-smokers (P=1.3×10-16) in comparison with 5% in ever-smokers (P=2.5×10-4), translating to a 60% loss of CHD protection conferred by this allelic variation in people who smoked tobacco (interaction P value=8.7×10-5). The protective T allele at rs7178051 was also associated with reduced ADAMTS7 expression in human aortic endothelial cells and lymphoblastoid cell lines. Exposure of human coronary artery smooth muscle cells to cigarette smoke extract led to induction of ADAMTS7. CONCLUSIONS: Allelic variation at rs7178051 that associates with reduced ADAMTS7 expression confers stronger CHD protection in never-smokers than in ever-smokers. Increased vascular ADAMTS7 expression may contribute to the loss of CHD protection in smokers.


Assuntos
Doença das Coronárias/genética , Doença das Coronárias/prevenção & controle , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Fumar/genética , Proteína ADAMTS7/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Doença das Coronárias/epidemiologia , Vasos Coronários/patologia , Vasos Coronários/fisiologia , Feminino , Interação Gene-Ambiente , Predisposição Genética para Doença/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fumar/efeitos adversos , Fumar/epidemiologia
15.
PLoS Med ; 14(4): e1002287, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28441426

RESUMO

INTRODUCTION: The molecular underpinnings of the dissociation of cognitive performance and neuropathological burden are poorly understood, and there are currently no known genetic or epigenetic determinants of the dissociation. METHODS AND FINDINGS: "Residual cognition" was quantified by regressing out the effects of cerebral pathologies and demographic characteristics on global cognitive performance proximate to death. To identify genes influencing residual cognition, we leveraged neuropathological, genetic, epigenetic, and transcriptional data available for deceased participants of the Religious Orders Study (n = 492) and the Rush Memory and Aging Project (n = 487). Given that our sample size was underpowered to detect genome-wide significance, we applied a multistep approach to identify genes influencing residual cognition, based on our prior observation that independent genetic and epigenetic risk factors can converge on the same locus. In the first step (n = 979), we performed a genome-wide association study with a predefined suggestive p < 10-5, and nine independent loci met this threshold in eight distinct chromosomal regions. Three of the six genes within 100 kb of the lead SNP are expressed in the dorsolateral prefrontal cortex (DLPFC): UNC5C, ENC1, and TMEM106B. In the second step, in the subset of participants with DLPFC DNA methylation data (n = 648), we found that residual cognition was related to differential DNA methylation of UNC5C and ENC1 (false discovery rate < 0.05). In the third step, in the subset of participants with DLPFC RNA sequencing data (n = 469), brain transcription levels of UNC5C and ENC1 were evaluated for their association with residual cognition: RNA levels of both UNC5C (estimated effect = -0.40, 95% CI -0.69 to -0.10, p = 0.0089) and ENC1 (estimated effect = 0.0064, 95% CI 0.0033 to 0.0096, p = 5.7 × 10-5) were associated with residual cognition. In secondary analyses, we explored the mechanism of these associations and found that ENC1 may be related to the previously documented effect of depression on cognitive decline, while UNC5C may alter the composition of presynaptic terminals. Of note, the TMEM106B allele identified in the first step as being associated with better residual cognition is in strong linkage disequilibrium with rs1990622A (r2 = 0.66), a previously identified protective allele for TDP-43 proteinopathy. Limitations include the small sample size for the genetic analysis, which was underpowered to detect genome-wide significance, the evaluation being limited to a single cortical region for epigenetic and transcriptomic data, and the use of categorical measures for certain non-amyloid-plaque, non-neurofibrillary-tangle neuropathologies. CONCLUSIONS: Through a multistep analysis of cognitive, neuropathological, genomic, epigenomic, and transcriptomic data, we identified ENC1 and UNC5C as genes with convergent genetic, epigenetic, and transcriptomic evidence supporting a potential role in the dissociation of cognition and neuropathology in an aging population, and we expanded our understanding of the TMEM106B haplotype that is protective against TDP-43 proteinopathy.


Assuntos
Envelhecimento/fisiologia , Encéfalo/patologia , Transtornos Cognitivos/genética , Cognição/fisiologia , Proteínas de Membrana/genética , Proteínas dos Microfilamentos/genética , Proteínas do Tecido Nervoso/genética , Neuropeptídeos/genética , Proteínas Nucleares/genética , Receptores de Superfície Celular/genética , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Alelos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Transtornos Cognitivos/metabolismo , Metilação de DNA , Depressão/metabolismo , Epigênese Genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Proteínas de Membrana/metabolismo , Memória , Proteínas dos Microfilamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Netrina , Neuropeptídeos/metabolismo , Proteínas Nucleares/metabolismo , Polimorfismo de Nucleotídeo Único , RNA/metabolismo , Receptores de Superfície Celular/metabolismo , Proteinopatias TDP-43/genética
16.
JAMA Neurol ; 74(3): 293-300, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28114441

RESUMO

Importance: Subclinical inflammatory demyelination and neurodegeneration often precede symptom onset in multiple sclerosis (MS). Objective: To investigate the prevalence of brain magnetic resonance imaging (MRI) and subclinical abnormalities among asymptomatic individuals at risk for MS. Design, Setting, and Participants: The Genes and Environment in Multiple Sclerosis (GEMS) project is a prospective cohort study of first-degree relatives of people with MS. Each participant's risk for MS was assessed using a weighted score (Genetic and Environmental Risk Score for Multiple Sclerosis Susceptibility [GERSMS]) comprising an individual's genetic burden and environmental exposures. The study dates were August 2012 to July 2015. Main Outcomes and Measures: Participants in the top and bottom 10% of the risk distribution underwent standard and quantitative neurological examination, including disability status, visual, cognitive, motor, and sensory testing, as well as qualitative and quantitative neuroimaging with 3-T brain MRI and optical coherence tomography. Results: This study included 100 participants at risk for MS, with 41 at higher risk (40 women [98%]) and 59 at lower risk (25 women [42%]), at a mean (SD) age of 35.1 (8.7) years. Given the unequal sex distribution between the 2 groups, the analyses were restricted to women (n = 65). When considering all measured outcomes, higher-risk women differed from lower-risk women (P = .01 by omnibus test). Detailed testing with a vibration sensitivity testing device in a subgroup of 47 women showed that higher-risk women exhibited significantly poorer vibration perception in the distal lower extremities (P = .008, adjusting for age, height, and testing date). Furthermore, 5 of 65 women (8%) (4 at higher risk and 1 at lower risk) met the primary neuroimaging outcome of having T2-weighted hyperintense brain lesions consistent with the 2010 McDonald MRI criteria for dissemination in space. A subset of participants harbor many different neuroimaging features associated with MS, including perivenous T2-weighted hyperintense lesions and focal leptomeningeal enhancement, consistent with the hypothesis that these individuals are at higher risk of developing clinical symptoms of MS than the general population. Conclusions and Relevance: Higher-risk asymptomatic family members of patients with MS are more likely to have early subclinical manifestations of MS. These findings underscore the importance of early detection in high-risk individuals. Trial Registration: clinicaltrials.gov Identifier: NCT01353547.


Assuntos
Saúde da Família , Esclerose Múltipla/complicações , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/genética , Doenças do Sistema Nervoso/etiologia , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Distribuição de Qui-Quadrado , Estudos de Coortes , Avaliação da Deficiência , Feminino , Humanos , Imagem Tridimensional , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Adulto Jovem
17.
Alzheimers Dement ; 13(6): 663-673, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27939925

RESUMO

INTRODUCTION: We hypothesized that common Alzheimer's disease (AD)-associated variants within the triggering receptor expressed on myeloid (TREM) gene cluster influence disease through gene expression. METHODS: Expression microarrays on temporal cortex and cerebellum from ∼400 neuropathologically diagnosed subjects and two independent RNAseq replication cohorts were used for expression quantitative trait locus analysis. RESULTS: A variant within a DNase hypersensitive site 5' of TREM2, rs9357347-C, associates with reduced AD risk and increased TREML1 and TREM2 levels (uncorrected P = 6.3 × 10-3 and 4.6 × 10-2, respectively). Meta-analysis on expression quantitative trait locus results from three independent data sets (n = 1006) confirmed these associations (uncorrected P = 3.4 × 10-2 and 3.5 × 10-3, Bonferroni-corrected P = 6.7 × 10-2 and 7.1 × 10-3, respectively). DISCUSSION: Our findings point to rs9357347 as a functional regulatory variant that contributes to a protective effect observed at the TREM locus in the International Genomics of Alzheimer's Project genome-wide association study meta-analysis and suggest concomitant increase in TREML1 and TREM2 brain levels as a potential mechanism for protection from AD.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Cerebelo/metabolismo , Feminino , Expressão Gênica , Predisposição Genética para Doença , Variação Genética , Humanos , Desequilíbrio de Ligação , Masculino , Análise em Microsséries , Família Multigênica , Locos de Características Quantitativas , Lobo Temporal/metabolismo
18.
Neurology ; 87(14): 1457-1463, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27605175

RESUMO

OBJECTIVE: To determine the association between hormone therapy (HT) and physical quality of life (QOL) in postmenopausal women with multiple sclerosis (MS). METHODS: We included female participants from the prospective Nurses' Health Study, with a diagnosis of definite or probable MS, who had completed a physical functioning assessment (PF10; subscale of the 36-Item Short-Form Health Survey QOL survey) at a time point between 3 and 10 years after their final menstrual period (early postmenopause). We assessed the association between HT use at this time point (never vs at least 12 months of systemic estrogen with/without progestin) and both PF10 and the 36-Item Short-Form Health Survey Physical Component Scale. We used a linear regression model adjusting for age, MS duration, menopause type and duration, and further for additional covariates (only ancestry was significant). RESULTS: Among 95 participants meeting all inclusion criteria at their first postmenopausal assessment, 61 reported HT use and 34 reported none. HT users differed from non-HT users in MS duration (p = 0.02) and menopause type (p = 0.01) but no other clinical or demographic characteristics. HT users had average PF10 scores that were 23 points higher than non-HT users (adjusted p = 0.004) and average Physical Component Scale scores that were 9.1 points higher in the 59 women with these available (adjusted p = 0.02). Longer duration of HT use was also associated with higher PF10 scores (p = 0.02, adjusted p = 0.06). CONCLUSIONS: Systemic HT use was associated with better physical QOL in postmenopausal women with MS in this observational study. Further studies are necessary to investigate causality.


Assuntos
Terapia de Reposição de Estrogênios , Esclerose Múltipla/epidemiologia , Pós-Menopausa , Qualidade de Vida , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Estudos Prospectivos , Inquéritos e Questionários
19.
Neurol Genet ; 2(4): e90, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27504496

RESUMO

OBJECTIVE: Given evidence from genetic studies, we hypothesized that there may be a shared component to the role of myeloid function in Parkinson and Alzheimer disease (PD and AD) and assessed whether PD susceptibility variants influenced protein expression of well-established AD-associated myeloid genes in human monocytes. METHODS: We repurposed data in which AD-related myeloid proteins CD33, TREM1, TREM2, TREML2, TYROBP, and PTK2B were measured by flow cytometry in monocytes from 176 participants of the PhenoGenetic Project (PGP) and Harvard Aging Brain Study. Linear regression was used to identify associations between 24 PD risk variants and protein expression. The 2 cohorts were meta-analyzed in a discovery analysis, and the 4 most strongly suggestive results were validated in an independent cohort of 50 PGP participants. RESULTS: We discovered and validated an association between the PD risk allele rs12456492(G) in the RIT2 locus and increased CD33 expression (p joint = 3.50 × 10(-5)) and found strongly suggestive evidence that rs11060180(A) in the CCDC62/HIP1R locus decreased PTK2B expression (p joint = 1.12 × 10(-4)). Furthermore, in older individuals, increased CD33 expression on peripheral monocytes was associated with a greater burden of parkinsonism (p = 0.047), particularly bradykinesia (p = 6.64 × 10(-3)). CONCLUSIONS: We find that the rs12456492 PD risk variant affects expression of AD-associated protein CD33 in peripheral monocytes, which suggests that genetic factors for these 2 diseases may converge to influence overlapping innate immune-mediated mechanisms that contribute to neurodegeneration. Furthermore, the effect of the rs12456492(G) PD risk allele on increased CD33 suggests that the inhibition of certain myeloid functions may contribute to PD susceptibility, as is the case for AD.

20.
PLoS One ; 11(7): e0157452, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27458716

RESUMO

BACKGROUND AND OBJECTIVE: Recently, we have shown that the Parkinson's disease (PD) susceptibility locus MAPT (microtubule associated protein tau) is associated with parkinsonism in older adults without a clinical diagnosis of PD. In this study, we investigated the relationship between parkinsonian signs and MAPT transcripts by assessing the effect of MAPT haplotypes on alternative splicing and expression levels of the most common isoforms in two prospective clinicopathologic studies of aging. MATERIALS AND METHODS: using regression analysis, controlling for age, sex, study and neuropathology, we evaluated 976 subjects with clinical, genotyping and brain pathology data for haplotype analysis. For transcript analysis, we obtained MAPT gene and isoform-level expression from the dorsolateral prefrontal cortex for 505 of these subjects. RESULTS: The MAPT H2 haplotype was associated with lower total MAPT expression (p = 1.2x10-14) and global parkinsonism at both study entry (p = 0.001) and proximate to death (p = 0.050). Specifically, haplotype H2 was primarily associated with bradykinesia in both assessments (p<0.001 and p = 0.008). MAPT total expression was associated with age and decreases linearly with advancing age (p<0.001). Analysing MAPT alternative splicing, the expression of 1N/4R isoform was inversely associated with global parkinsonism (p = 0.008) and bradykinesia (p = 0.008). Diminished 1N/4R isoform expression was also associated with H2 (p = 0.001). CONCLUSIONS: Overall, our results suggest that age and H2 are associated with higher parkinsonism score and decreased total MAPT RNA expression. Additionally, we found that H2 and parkinsonism are associated with altered expression levels of specific isoforms. These findings may contribute to the understanding of the association between MAPT locus and parkinsonism in elderly subjects and in some extent to age-related neurodegenerative diseases.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Transtornos Parkinsonianos/genética , Proteínas tau/genética , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Processamento Alternativo , Encéfalo/metabolismo , Encéfalo/patologia , Diagnóstico , Feminino , Expressão Gênica , Genótipo , Humanos , Masculino , Doença de Parkinson/genética , Transtornos Parkinsonianos/diagnóstico , Transtornos Parkinsonianos/mortalidade , Fenótipo , Isoformas de Proteínas , Característica Quantitativa Herdável
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