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AIMS: Although highly heritable, the genetic etiology of calcific aortic stenosis (AS) remains incompletely understood. The aim of this study was to discover novel genetic contributors to AS and to integrate functional, expression, and cross-phenotype data to identify mechanisms of AS. METHODS AND RESULTS: A genome-wide meta-analysis of 11.6 million variants in 10 cohorts involving 653 867 European ancestry participants (13 765 cases) was performed. Seventeen loci were associated with AS at P ≤ 5 × 10-8, of which 15 replicated in an independent cohort of 90 828 participants (7111 cases), including CELSR2-SORT1, NLRP6, and SMC2. A genetic risk score comprised of the index variants was associated with AS [odds ratio (OR) per standard deviation, 1.31; 95% confidence interval (CI), 1.26-1.35; P = 2.7 × 10-51] and aortic valve calcium (OR per standard deviation, 1.22; 95% CI, 1.08-1.37; P = 1.4 × 10-3), after adjustment for known risk factors. A phenome-wide association study indicated multiple associations with coronary artery disease, apolipoprotein B, and triglycerides. Mendelian randomization supported a causal role for apolipoprotein B-containing lipoprotein particles in AS (OR per g/L of apolipoprotein B, 3.85; 95% CI, 2.90-5.12; P = 2.1 × 10-20) and replicated previous findings of causality for lipoprotein(a) (OR per natural logarithm, 1.20; 95% CI, 1.17-1.23; P = 4.8 × 10-73) and body mass index (OR per kg/m2, 1.07; 95% CI, 1.05-1.9; P = 1.9 × 10-12). Colocalization analyses using the GTEx database identified a role for differential expression of the genes LPA, SORT1, ACTR2, NOTCH4, IL6R, and FADS. CONCLUSION: Dyslipidemia, inflammation, calcification, and adiposity play important roles in the etiology of AS, implicating novel treatments and prevention strategies.
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Estenose da Valva Aórtica , Dislipidemias , Humanos , Estudo de Associação Genômica Ampla/métodos , Adiposidade/genética , Predisposição Genética para Doença , Estenose da Valva Aórtica/genética , Obesidade , Fatores de Risco , Inflamação , Dislipidemias/complicações , Dislipidemias/genética , Apolipoproteínas/genética , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
INTRODUCTION: Plasma has been proposed as an alternative to cerebrospinal fluid (CSF) for measuring Alzheimer's disease (AD) biomarkers, but no studies have analyzed in detail which biofluid is more informative for genetics studies of AD. METHOD: Eleven proteins associated with AD (α-synuclein, apolipoprotein E [apoE], CLU, GFAP, GRN, NfL, NRGN, SNAP-25, TREM2, VILIP-1, YKL-40) were assessed in plasma (n = 2317) and CSF (n = 3107). Both plasma and CSF genome-wide association study (GWAS) analyses were performed for each protein, followed by functional annotation. Additional characterization for each biomarker included calculation of correlations and predictive power. RESULTS: Eighteen plasma protein quantitative train loci (pQTLs) associated with 10 proteins and 16 CSF pQTLs associated with 9 proteins were identified. Plasma and CSF shared some genetic loci, but protein levels between tissues correlated weakly. CSF protein levels better associated with AD compared to plasma. DISCUSSION: The present results indicate that CSF is more informative than plasma for genetic studies in AD. HIGHLIGHTS: The identification of novel protein quantitative trait loci (pQTLs) in both plasma and cerebrospinal fluid (CSF). Plasma and CSF levels of neurodegeneration-related proteins correlated weakly. CSF is more informative than plasma for genetic studies of Alzheimer's disease (AD). Neurofilament light (NfL), triggering receptor expressed on myeloid cells 2 (TREM2), and chitinase-3-like protein 1 (YKL-40) tend to show relatively strong inter-tissue associations. A novel signal in the apolipoprotein E (APOE) region was identified, which is an eQTL for APOC1.
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BACKGROUND: Genome-wide association studies (GWAS) of Alzheimer's disease (AD) have identified several risk loci, but many remain unknown. Cerebrospinal fluid (CSF) biomarkers may aid in gene discovery and we previously demonstrated that six CSF biomarkers (ß-amyloid, total/phosphorylated tau, NfL, YKL-40, and neurogranin) cluster into five principal components (PC), each representing statistically independent biological processes. Here, we aimed to (1) identify common genetic variants associated with these CSF profiles, (2) assess the role of associated variants in AD pathophysiology, and (3) explore potential sex differences. METHODS: We performed GWAS for each of the five biomarker PCs in two multi-center studies (EMIF-AD and ADNI). In total, 973 participants (n = 205 controls, n = 546 mild cognitive impairment, n = 222 AD) were analyzed for 7,433,949 common SNPs and 19,511 protein-coding genes. Structural equation models tested whether biomarker PCs mediate genetic risk effects on AD, and stratified and interaction models probed for sex-specific effects. RESULTS: Five loci showed genome-wide significant association with CSF profiles, two were novel (rs145791381 [inflammation] and GRIN2D [synaptic functioning]) and three were previously described (APOE, TMEM106B, and CHI3L1). Follow-up analyses of the two novel signals in independent datasets only supported the GRIN2D locus, which contains several functionally interesting candidate genes. Mediation tests indicated that variants in APOE are associated with AD status via processes related to amyloid and tau pathology, while markers in TMEM106B and CHI3L1 are associated with AD only via neuronal injury/inflammation. Additionally, seven loci showed sex-specific associations with AD biomarkers. CONCLUSIONS: These results suggest that pathway and sex-specific analyses can improve our understanding of AD genetics and may contribute to precision medicine.
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Doença de Alzheimer , Humanos , Feminino , Masculino , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Estudo de Associação Genômica Ampla , Proteínas tau/genética , Biomarcadores , Inflamação , Apolipoproteínas E/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Receptores de N-Metil-D-Aspartato/genéticaRESUMO
Background: Poorer health outcomes experienced by young women with acute coronary syndrome may be related to sex differences in the safety and efficacy of antiplatelet agents, such as clopidogrel. Polymorphisms in drug metabolism enzyme (cytochrome P450 [CYP] family) genes are independent factors for the variability in response to clopidogrel. However, a sex-specific impact of genetics to explain worse clinical outcomes in women has not been explored extensively. Therefore, our objective was to determine whether an interaction of sex with CYP variants occurs among users of clopidogrel, and if so, its impact on 1-year adverse clinical outcomes. Methods: We used data from a combined cohort of 2272 patients (median age 49 years; 56% female) hospitalized for acute coronary syndrome. We examined interactions between sex and CYP variants among clopidogrel users at admission and discharge to assess associations with 1-year readmission due to cardiac events. Results: The case-only analysis of 177 participants on clopidogrel at the time of presentation showed that the risk of an atherothrombotic event was greater in female carriers of the CYP2C9∗3 loss-of-function allele (odds ratio = 3.77, 95% confidence interval = 1.54-9.24). The results of the multivariable logistic regression model for users of clopidogrel at discharge (n = 1733) indicated that women had significantly higher risk of atherothrombotic readmissions at 1 year (odds ratio = 1.55, 95% confidence interval = 1.16-2.07), compared to the risk for men, but the loss-of-function alleles, either individually or through a genetic risk score, were not associated with 1-year readmissions. Conclusion: This study highlights the need for an improved understanding of the role of sex-by-gene interactions in causing sex differences in drug metabolism.
Contexte: Les piètres résultats cliniques observés chez les jeunes femmes atteintes d'un syndrome coronarien aigu pourraient être liés à des différences entre les sexes en ce qui concerne l'innocuité et l'efficacité des antiplaquettaires, comme le clopidogrel. Le polymorphisme génétique des enzymes intervenant dans le métabolisme des médicaments (famille des cytochromes P450 [CYP]) est un facteur indépendant de la variabilité de la réponse au clopidogrel. Cependant, jamais la possibilité d'un effet génétique propre au sexe qui expliquerait les résultats cliniques défavorables chez les femmes n'a été examinée en profondeur. Notre objectif était donc de déterminer s'il se produit une interaction entre le sexe et les variants de CYP chez les personnes prenant du clopidogrel et, si tel est le cas, quels sont ses effets sur les résultats cliniques indésirables après un an. Méthodologie: Nous avons utilisé les données d'une cohorte combinée de 2 272 patients (âge médian : 49 ans; 56 % de femmes) hospitalisés en raison d'un syndrome coronarien aigu. Nous avons examiné les interactions entre le sexe et les variants du CYP chez les utilisateurs de clopidogrel au moment de leur admission à l'hôpital et de leur congé pour évaluer les liens entre ces variables et les réhospitalisations après un an en raison d'événements cardiaques. Résultats: L'analyse de cas de 177 participants prenant du clopidogrel au moment de leur admission à l'hôpital a montré que le risque d'événement athérothrombotique était plus élevé chez les femmes porteuses de l'allèle non fonctionnel CYP2C9∗3 (rapport de cotes = 3,77; intervalle de confiance [IC] à 95 % = 1,54 à 9,24). Les résultats obtenus avec le modèle de régression logistique multivariée pour les utilisateurs de clopidogrel au moment du congé (n = 1 733) indiquent que les femmes présentaient un risque significativement plus élevé de réhospitalisation en raison d'un événement athérothrombotique après un an (rapport de cotes = 1,55; [IC] à 95 % = 1,16 à 2,07), comparativement aux hommes. Toutefois, les allèles non fonctionnels, considérés individuellement ou sur la base d'un score de risque génétique, n'étaient pas liés à la réhospitalisation après un an. Conclusion: Cette étude fait ressortir la nécessité de mieux comprendre le rôle de l'interaction sexe-gène dans les différences entre les sexes relativement au métabolisme des médicaments.
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Alp/Enigma family members have a unique PDZ domain followed by zero to four LIM domains, and are essential for myofibril assembly across all species analyzed so far. Drosophila melanogaster has three Alp/Enigma family members, Zasp52, Zasp66, and Zasp67. Ortholog search and phylogenetic tree analysis suggest that Zasp genes have a common ancestor, and that Zasp66 and Zasp67 arose by duplication in insects. While Zasp66 has a conserved domain structure across orthologs, Zasp67 domains and lengths are highly variable. In flies, Zasp67 appears to be expressed only in indirect flight muscles, where it colocalizes with Zasp52 at Z-discs. We generated a CRISPR null mutant of Zasp67, which is viable but flightless. We can rescue all phenotypes by re-expressing a Zasp67 transgene at endogenous levels. Zasp67 mutants show extended and broken Z-discs in adult flies, indicating that the protein helps stabilize the highly regular myofibrils of indirect flight muscles. In contrast, a Zasp66 CRISPR null mutant has limited viability, but only mild indirect flight muscle defects illustrating the diverging evolutionary paths these two paralogous genes have taken since they arose by duplication.