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1.
J Am Heart Assoc ; 8(10): e011922, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31070104

RESUMO

Background Recent studies have revealed sexually dimorphic associations between the carbamoyl-phosphate synthase 1 locus, intermediates of the metabolic pathway leading from choline to urea, and risk of coronary artery disease ( CAD ) in women. Based on evidence from the literature, the atheroprotective association with carbamoyl-phosphate synthase 1 could be mediated by the strong genetic effect of this locus on increased circulating glycine levels. Methods and Results We sought to identify additional genetic determinants of circulating glycine levels by carrying out a meta-analysis of genome-wide association study data in up to 30 118 subjects of European ancestry. Mendelian randomization and other analytical approaches were used to determine whether glycine-associated variants were associated with CAD and traditional risk factors. Twelve loci were significantly associated with circulating glycine levels, 7 of which were not previously known to be involved in glycine metabolism ( ACADM , PHGDH , COX 18- ADAMTS 3, PSPH , TRIB 1, PTPRD , and ABO ). Glycine-raising alleles at several loci individually exhibited directionally consistent associations with decreased risk of CAD . However, these effects could not be attributed directly to glycine because of associations with other CAD -related traits. By comparison, genetic models that only included the 2 variants directly involved in glycine degradation and for which there were no other pleiotropic associations were not associated with risk of CAD or blood pressure, lipid levels, and obesity-related traits. Conclusions These results provide additional insight into the genetic architecture of glycine metabolism, but do not yield conclusive evidence for a causal relationship between circulating levels of this amino acid and risk of CAD in humans.

2.
Circ Genom Precis Med ; 12(4): e002470, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30896328

RESUMO

BACKGROUND: The Genetics of Subsequent Coronary Heart Disease (GENIUS-CHD) consortium was established to facilitate discovery and validation of genetic variants and biomarkers for risk of subsequent CHD events, in individuals with established CHD. METHODS: The consortium currently includes 57 studies from 18 countries, recruiting 185 614 participants with either acute coronary syndrome, stable CHD, or a mixture of both at baseline. All studies collected biological samples and followed-up study participants prospectively for subsequent events. RESULTS: Enrollment into the individual studies took place between 1985 to present day with a duration of follow-up ranging from 9 months to 15 years. Within each study, participants with CHD are predominantly of self-reported European descent (38%-100%), mostly male (44%-91%) with mean ages at recruitment ranging from 40 to 75 years. Initial feasibility analyses, using a federated analysis approach, yielded expected associations between age (hazard ratio, 1.15; 95% CI, 1.14-1.16) per 5-year increase, male sex (hazard ratio, 1.17; 95% CI, 1.13-1.21) and smoking (hazard ratio, 1.43; 95% CI, 1.35-1.51) with risk of subsequent CHD death or myocardial infarction and differing associations with other individual and composite cardiovascular endpoints. CONCLUSIONS: GENIUS-CHD is a global collaboration seeking to elucidate genetic and nongenetic determinants of subsequent event risk in individuals with established CHD, to improve residual risk prediction and identify novel drug targets for secondary prevention. Initial analyses demonstrate the feasibility and reliability of a federated analysis approach. The consortium now plans to initiate and test novel hypotheses as well as supporting replication and validation analyses for other investigators.

3.
Circ Genom Precis Med ; 12(4): e002471, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30897348

RESUMO

BACKGROUND: Genetic variation at chromosome 9p21 is a recognized risk factor for coronary heart disease (CHD). However, its effect on disease progression and subsequent events is unclear, raising questions about its value for stratification of residual risk. METHODS: A variant at chromosome 9p21 (rs1333049) was tested for association with subsequent events during follow-up in 103 357 Europeans with established CHD at baseline from the GENIUS-CHD (Genetics of Subsequent Coronary Heart Disease) Consortium (73.1% male, mean age 62.9 years). The primary outcome, subsequent CHD death or myocardial infarction (CHD death/myocardial infarction), occurred in 13 040 of the 93 115 participants with available outcome data. Effect estimates were compared with case/control risk obtained from the CARDIoGRAMplusC4D consortium (Coronary Artery Disease Genome-wide Replication and Meta-analysis [CARDIoGRAM] plus The Coronary Artery Disease [C4D] Genetics) including 47 222 CHD cases and 122 264 controls free of CHD. RESULTS: Meta-analyses revealed no significant association between chromosome 9p21 and the primary outcome of CHD death/myocardial infarction among those with established CHD at baseline (GENIUS-CHD odds ratio, 1.02; 95% CI, 0.99-1.05). This contrasted with a strong association in CARDIoGRAMPlusC4D odds ratio 1.20; 95% CI, 1.18-1.22; P for interaction <0.001 compared with the GENIUS-CHD estimate. Similarly, no clear associations were identified for additional subsequent outcomes, including all-cause death, although we found a modest positive association between chromosome 9p21 and subsequent revascularization (odds ratio, 1.07; 95% CI, 1.04-1.09). CONCLUSIONS: In contrast to studies comparing individuals with CHD to disease-free controls, we found no clear association between genetic variation at chromosome 9p21 and risk of subsequent acute CHD events when all individuals had CHD at baseline. However, the association with subsequent revascularization may support the postulated mechanism of chromosome 9p21 for promoting atheroma development.

4.
Sci Rep ; 9(1): 1816, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755631

RESUMO

Emerging evidence from epidemiological and animal studies suggests that exposure to traffic-related air pollutants and particulate matter less than 2.5 µm in diameter (PM2.5) contributes to development of obesity and related metabolic abnormalities. However, it is not known whether nanoscale particulate matter (nPM) with aerodynamic diameter ≤200 nm have similar adverse metabolic effects. The goal of the present study was to determine the effects of prenatal and early life exposure to nPM on metabolic homeostasis in mice. C57BL/6 J mice were exposed to nPM or filtered air from gestation until 17 weeks of age and characterized for metabolic and behavioral parameters. In male mice, nPM exposure increased food intake, body weight, fat mass, adiposity, and whole-body glucose intolerance (p < 0.05). Consistent with these effects, male mice exposed to nPM displayed alterations in the expression of metabolically-relevant neuropeptides in the hypothalamus and decreased expression of insulin receptor signaling genes in adipose (p < 0.05). There were no differences in exploratory behavior or motor function, fasting lipid levels, or the inflammatory profile of adipose tissue. Our results provide evidence that chronic nPM exposure from gestation to early adulthood in male mice promotes metabolic dysregulation in part through modulation of feeding behavior and in the absence of an obesogenic diet.

5.
JCI Insight ; 3(6)2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-29563342

RESUMO

Using an untargeted metabolomics approach in initial (N = 99 subjects) and replication cohorts (N = 1,162), we discovered and structurally identified a plasma metabolite associated with cardiovascular disease (CVD) risks, N6,N6,N6-trimethyl-L-lysine (trimethyllysine, TML). Stable-isotope-dilution tandem mass spectrometry analyses of an independent validation cohort (N = 2,140) confirmed TML levels are independently associated with incident (3-year) major adverse cardiovascular event risks (hazards ratio [HR], 2.4; 95% CI, 1.7-3.4) and incident (5-year) mortality risk (HR, 2.9; 95% CI, 2.0-4.2). Genome-wide association studies identified several suggestive loci for TML levels, but none reached genome-wide significance; and d9(trimethyl)-TML isotope tracer studies confirmed TML can serve as a nutrient precursor for gut microbiota-dependent generation of trimethylamine (TMA) and the atherogenic metabolite trimethylamine N-oxide (TMAO). Although TML was shown to be abundant in both plant- and animal-derived foods, mouse and human fecal cultures (omnivores and vegans) showed slow conversion of TML to TMA. Furthermore, unlike chronic dietary choline, TML supplementation in mice failed to elevate plasma TMAO or heighten thrombosis potential in vivo. Thus, TML is identified as a strong predictor of incident CVD risks in subjects and to serve as a dietary precursor for gut microbiota-dependent generation of TMAO; however, TML does not appear to be a major microbial source for TMAO generation in vivo.

6.
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
7.
Curr Atheroscler Rep ; 19(2): 6, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28130654

RESUMO

PURPOSE OF REVIEW: We provide an overview of our current understanding of the genetic architecture of coronary artery disease (CAD) and discuss areas of research that provide excellent opportunities for further exploration. RECENT FINDINGS: Large-scale studies in human populations, coupled with rapid advances in genetic technologies over the last decade, have clearly established the association of common genetic variation with risk of CAD. However, the effect sizes of the susceptibility alleles are for the most part modest and collectively explain only a small fraction of the overall heritability. By comparison, evidence that rare variants make a substantial contribution to risk of CAD has been somewhat disappointing thus far, suggesting that other biological mechanisms have yet to be discovered. Emerging data suggests that novel pathways involved in the development of CAD can be identified through complementary and integrative systems genetics strategies in mice or humans. There is also convincing evidence that gut bacteria play a previously unrecognized role in the development of CAD, particularly through metabolism of certain dietary nutrients that lead to proatherogenic metabolites in the circulation. A major effort is now underway to functionally understand the newly discovered genetic and biological associations for CAD, which could lead to the development of potentially novel therapeutic strategies. Other important areas of investigation for understanding the pathophysiology of CAD, including epistatic interactions between genes or with either sex and environmental factors, have not been studied on a broad scope and represent additional opportunities for future studies.


Assuntos
Doença da Artéria Coronariana/genética , Alelos , Animais , Predisposição Genética para Doença , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Fatores de Risco
8.
J Nutrigenet Nutrigenomics ; 10(5-6): 155-162, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29339647

RESUMO

The International Society of Nutrigenetics and Nutrigenomics (ISNN) held its 11th annual Congress in Los Angeles, California, between September 16 and 19, 2017. In addition to 2 keynote lectures, 4 plenary sessions included presentations by internationally renowned speakers on cutting-edge areas of research and new discoveries in genetics/genomics, the microbiome, and nutrition. Scientific topics included multi-omics approaches; diet and the microbiome; cancer, longevity, and metabolism; moving the field forward; and translational/educational aspects and the future of medicine. There was also an accepted oral abstracts session designed specifically to provide young investigators and trainees with the opportunity to present their work, as well as a session focused on industry-academic partnerships, which included a roundtable discussion afterwards. Overall, the 11th ISNN Congress was an exciting and intellectually stimulating meeting focused on understanding the impact of biological interactions between genes and nutrients on health and disease. These efforts continued the decade-long tradition of the annual ISNN Congress to provide an interdisciplinary platform for scientists from various disciplines to discuss research ideas and advance the fields of nutrigenetics and nutrigenomics.

9.
J Assoc Res Otolaryngol ; 17(5): 417-31, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27539716

RESUMO

This study aimed to investigate the genetic causes of vestibular dysfunction. We used vestibular sensory-evoked potentials (VsEPs) to characterize the vestibular function of 35 inbred mouse strains selected from the Hybrid Mouse Diversity Panel and demonstrated strain-dependent phenotypic variation in vestibular function. Using these phenotypic data, we performed the first genome-wide association study controlling for population structure that has revealed two highly suggestive loci, one of which lies within a haplotype block containing five genes (Stard6, 4930503L19Rik, Poli, Mbd2, Dcc) on Chr. 18 (peak SNP rs29632020), one gene, deleted in colorectal carcinoma (Dcc) has a well-established role in nervous system development. An in-depth analysis of Dcc-deficient mice demonstrated elevation in mean VsEP threshold for Dcc (+/-) mice (-11.86 dB) compared to wild-type (-9.68 dB) littermates. Synaptic ribbon studies revealed Dcc (-/-) (P0) and Dcc (+/-) (6-week-old) mice showed lower density of the presynaptic marker (CtBP2) as compared to wild-type controls. Vestibular ganglion cell counts of Dcc (-/-) (P0) was lower than controls. Whole-mount preparations showed abnormal innervation of the utricle, saccule, and crista ampullaris at E14.5, E16.5, and E18.5. Postnatal studies were limited by the perinatal lethality in Dcc (-/-) mice. Expression analyses using in situ hybridization and immunohistochemistry showed Dcc expression in the mouse vestibular ganglion (E15.5), and utricle and crista ampullaris (6-week-old), respectively. In summary, we report the first GWAS for vestibular functional variation in inbred mice and provide evidence for the role of Dcc in the normal innervation of the peripheral vestibular system.


Assuntos
Receptor DCC/fisiologia , Vestíbulo do Labirinto/inervação , Animais , Potenciais Evocados , Feminino , Estudo de Associação Genômica Ampla , Masculino , Camundongos , Vestíbulo do Labirinto/metabolismo
10.
J Am Heart Assoc ; 5(8)2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-27468926

RESUMO

BACKGROUND: The effect of air pollution exposure on atherosclerosis severity or incident clinical events in patients with coronary artery disease is not known. METHODS AND RESULTS: We conducted a prospective longitudinal cohort study of 6575 Ohio residents undergoing elective diagnostic coronary angiography. Multinomial regression and Cox proportional hazards models were used to assess the relationship between exposure to fine particulate matter <2.5 µm in diameter (PM2.5) and nitrogen dioxide on coronary artery disease severity at baseline and risk of myocardial infarction, stroke, or all-cause mortality over 3 years of follow-up. Among participants with coronary artery disease, exposure to PM2.5 levels was associated with increased likelihood of having coronary atherosclerosis that was mild (odds ratio 1.43, 95% CI 1.11-1.83, P=0.005) and severe (odds ratio 1.63, 95% CI 1.26-2.11, P<0.0001), with the effect on severe coronary artery disease being significantly increased compared with mild disease (Ptrend=0.03). Exposure to higher PM2.5 levels was also significantly associated with increased risk of incident myocardial infarction (hazard ratio 1.33, 95% CI 1.02-1.73, P=0.03) but not stroke or all-cause mortality. The association of PM2.5 with incident myocardial infarction was not affected after adjustment for Framingham Adult Treatment Panel III (ATP III) risk score or statin therapy. In comparison, there were no significant associations between nitrogen dioxide levels and all-cause mortality or risk of stroke after adjustment for Framingham ATP III risk score. CONCLUSIONS: Exposure to PM2.5 increased the likelihood of having severe coronary artery disease and the risk of incident myocardial infarction among patients undergoing elective cardiac evaluation. These results suggest that ambient air pollution exposure may be a modifiable risk factor for risk of myocardial infarction in a highly susceptible patient population.


Assuntos
Poluição do Ar/efeitos adversos , Doença da Artéria Coronariana/induzido quimicamente , Infarto do Miocárdio/induzido quimicamente , Idoso , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Doença da Artéria Coronariana/epidemiologia , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Óxido Nítrico/efeitos adversos , Ohio/epidemiologia , Material Particulado/efeitos adversos , Estudos Prospectivos
11.
Nat Commun ; 7: 10558, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26822151

RESUMO

Metabolites derived from dietary choline and L-carnitine, such as trimethylamine N-oxide and betaine, have recently been identified as novel risk factors for atherosclerosis in mice and humans. We sought to identify genetic factors associated with plasma betaine levels and determine their effect on risk of coronary artery disease (CAD). A two-stage genome-wide association study (GWAS) identified two significantly associated loci on chromosomes 2q34 and 5q14.1. The lead variant on 2q24 (rs715) localizes to carbamoyl-phosphate synthase 1 (CPS1), which encodes a mitochondrial enzyme that catalyses the first committed reaction and rate-limiting step in the urea cycle. Rs715 is also significantly associated with decreased levels of urea cycle metabolites and increased plasma glycine levels. Notably, rs715 yield a strikingly significant and protective association with decreased risk of CAD in only women. These results suggest that glycine metabolism and/or the urea cycle represent potentially novel sex-specific mechanisms for the development of atherosclerosis.


Assuntos
Carbamoil-Fosfato Sintase (Amônia)/metabolismo , Doença das Coronárias/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Predisposição Genética para Doença , Betaína/sangue , Carbamoil-Fosfato Sintase (Amônia)/genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Metabolômica , Polimorfismo de Nucleotídeo Único , Fatores Sexuais
12.
Nat Genet ; 47(11): 1282-1293, 2015 11.
Artigo em Inglês | MEDLINE | ID: mdl-26390057

RESUMO

We carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 × 10(-11) to 5.0 × 10(-21)). The sentinel blood pressure SNPs are enriched for association with DNA methylation at multiple nearby CpG sites, suggesting that, at some of the loci identified, DNA methylation may lie on the regulatory pathway linking sequence variation to blood pressure. The sentinel SNPs at the 12 new loci point to genes involved in vascular smooth muscle (IGFBP3, KCNK3, PDE3A and PRDM6) and renal (ARHGAP24, OSR1, SLC22A7 and TBX2) function. The new and known genetic variants predict increased left ventricular mass, circulating levels of NT-proBNP, and cardiovascular and all-cause mortality (P = 0.04 to 8.6 × 10(-6)). Our results provide new evidence for the role of DNA methylation in blood pressure regulation.


Assuntos
Pressão Sanguínea/genética , Metilação de DNA , Loci Gênicos/genética , Estudo de Associação Genômica Ampla/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Asiático/genética , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/genética , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Predisposição Genética para Doença/etnologia , Predisposição Genética para Doença/genética , Variação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Polimorfismo de Nucleotídeo Único , Análise de Regressão , Fatores de Risco
13.
G3 (Bethesda) ; 5(11): 2329-39, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26342000

RESUMO

Genome-wide association studies (GWAS) have been successfully applied in humans for the study of many complex phenotypes. However, identification of the genetic determinants of hearing in adults has been hampered, in part, by the relative inability to control for environmental factors that might affect hearing throughout the lifetime, as well as a large degree of phenotypic heterogeneity. These and other factors have limited the number of large-scale studies performed in humans that have identified candidate genes that contribute to the etiology of this complex trait. To address these limitations, we performed a GWAS analysis using a set of inbred mouse strains from the Hybrid Mouse Diversity Panel. Among 99 strains characterized, we observed approximately two-fold to five-fold variation in hearing at six different frequencies, which are differentiated biologically from each other by the location in the cochlea where each frequency is registered. Among all frequencies tested, we identified a total of nine significant loci, several of which contained promising candidate genes for follow-up study. Taken together, our results indicate the existence of both genes that affect global cochlear function, as well as anatomical- and frequency-specific genes, and further demonstrate the complex nature of mammalian hearing variation.


Assuntos
Genoma , Perda Auditiva/genética , Locos de Características Quantitativas , Animais , Limiar Auditivo , Feminino , Estudo de Associação Genômica Ampla , Camundongos , Camundongos Endogâmicos
14.
Stem Cell Reports ; 5(1): 125-38, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26050929

RESUMO

Prior efforts to identify regulators of hematopoietic stem cell physiology have relied mainly on candidate gene approaches with genetically modified mice. Here we used a genome-wide association study (GWAS) strategy with the hybrid mouse diversity panel to identify the genetic determinants of hematopoietic stem/progenitor cell (HSPC) frequency. Among 108 strains, we observed ∼120- to 300-fold variation in three HSPC populations. A GWAS analysis identified several loci that were significantly associated with HSPC frequency, including a locus on chromosome 5 harboring the homeodomain-only protein gene (Hopx). Hopx previously had been implicated in cardiac development but was not known to influence HSPC biology. Analysis of the HSPC pool in Hopx-/- mice demonstrated significantly reduced cell frequencies and impaired engraftment in competitive repopulation assays, thus providing functional validation of this positional candidate gene. These results demonstrate the power of GWAS in mice to identify genetic determinants of the hematopoietic system.


Assuntos
Estudo de Associação Genômica Ampla , Células-Tronco Hematopoéticas , Proteínas de Homeodomínio/genética , Animais , Linhagem da Célula/genética , Proliferação de Células/genética , Camundongos , Camundongos Knockout
15.
Early Hum Dev ; 91(8): 483-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26073892

RESUMO

BACKGROUND: Vitamin D is essential for proper neurodevelopment and cognitive and behavioral function. We examined associations between autism spectrum disorder (ASD) and common, functional polymorphisms in vitamin D pathways. METHODS: Children aged 24-60 months enrolled from 2003 to 2009 in the population-based CHARGE case-control study were evaluated clinically and confirmed to have ASD (n=474) or typical development (TD, n=281). Maternal, paternal, and child DNA samples for 384 (81%) families of children with ASD and 234 (83%) families of TD children were genotyped for: TaqI, BsmI, FokI, and Cdx2 in the vitamin D receptor (VDR) gene, and CYP27B1 rs4646536, GC rs4588, and CYP2R1 rs10741657. Case-control logistic regression, family-based log-linear, and hybrid log-linear analyses were conducted to produce risk estimates and 95% confidence intervals (CI) for each allelic variant. RESULTS: Paternal VDR TaqI homozygous variant genotype was significantly associated with ASD in case-control analysis (odds ratio [OR] [CI]: 6.3 [1.9-20.7]) and there was a trend towards increased risk associated with VDR BsmI (OR [CI]: 4.7 [1.6-13.4]). Log-linear triad analyses detected parental imprinting, with greater effects of paternally-derived VDR alleles. Child GC AA-genotype/A-allele was associated with ASD in log-linear and ETDT analyses. A significant association between decreased ASD risk and child CYP2R1 AA-genotype was found in hybrid log-linear analysis. There were limitations of low statistical power for less common alleles due to missing paternal genotypes. CONCLUSIONS: This study provides preliminary evidence that paternal and child vitamin D metabolism could play a role in the etiology of ASD; further research in larger study populations is warranted.


Assuntos
Transtorno do Espectro Autista/genética , Colestanotriol 26-Mono-Oxigenase/genética , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Adulto , Estudos de Casos e Controles , Pré-Escolar , Família 2 do Citocromo P450 , Pai , Feminino , Humanos , Masculino , Vitamina D/sangue
16.
Invest Ophthalmol Vis Sci ; 56(4): 2737-48, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25813999

RESUMO

PURPOSE: The pathophysiology of ocular hypertension (OH) leading to primary open-angle glaucoma shares many features with a secondary form of OH caused by treatment with glucocorticoids, but also exhibits distinct differences. In this study, a pharmacogenomics approach was taken to discover candidate genes for this disorder. METHODS: A genome-wide association study was performed, followed by an independent candidate gene study, using a cohort enrolled from patients treated with off-label intravitreal triamcinolone, and handling change in IOP as a quantitative trait. RESULTS: An intergenic quantitative trait locus (QTL) was identified at chromosome 6p21.33 near the 5' end of HCG22 that attained the accepted statistical threshold for genome-level significance. The HCG22 transcript, encoding a novel mucin protein, was expressed in trabecular meshwork cells, and expression was stimulated by IL-1, and inhibited by triamcinolone acetate and TGF-ß. Bioinformatic analysis defined the QTL as an approximately 4 kilobase (kb) linkage disequilibrium block containing 10 common single nucleotide polymorphisms (SNPs). Four of these SNPs were identified in the National Center for Biotechnology Information (NCBI) GTEx eQTL browser as modifiers of HCG22 expression. Most are predicted to disrupt or improve motifs for transcription factor binding, the most relevant being disruption of the glucocorticoid receptor binding motif. A second QTL was identified within the predicted signal peptide of the HCG22 encoded protein that could affect its secretion. Translation, O-glycosylation, and secretion of the predicted HCG22 protein was verified in cultured trabecular meshwork cells. CONCLUSIONS: Identification of two independent QTLs that could affect expression of the HCG22 mucin gene product via two different mechanisms (transcription or secretion) is highly suggestive of a role in steroid-induced OH.


Assuntos
Regulação da Expressão Gênica , Pressão Intraocular/efeitos dos fármacos , Mucinas/genética , Hipertensão Ocular/genética , RNA Mensageiro/genética , Triancinolona/efeitos adversos , Adulto , Feminino , Seguimentos , Estudo de Associação Genômica Ampla , Genótipo , Glucocorticoides/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Mucinas/biossíntese , Hipertensão Ocular/induzido quimicamente , Hipertensão Ocular/metabolismo , Malha Trabecular/metabolismo
17.
Diabetologia ; 57(7): 1391-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24728128

RESUMO

AIMS/HYPOTHESIS: MTNR1B is a type 2 diabetes susceptibility locus associated with cross-sectional measures of insulin secretion. We hypothesised that variation in MTNR1B contributes to the absolute level of a diabetes-related trait, temporal rate of change in that trait, or both. METHODS: We tested rs10830963 for association with cross-sectional diabetes-related traits in up to 1,383 individuals or with rate of change in the same phenotypes over a 3-5 year follow-up in up to 374 individuals from the family-based BetaGene study of Mexican Americans. RESULTS: rs10830963 was associated cross-sectionally with fasting glucose (p = 0.0069), acute insulin response (AIR; p = 0.0013), disposition index (p = 0.00078), glucose effectiveness (p = 0.018) and gestational diabetes mellitus (OR 1.48; p = 0.012), but not with OGTT 30 min Δinsulin (the difference between the 30 min and fasting plasma insulin concentration) or 30 min insulin-based disposition index. rs10830963 was also associated with rate of change in fasting glucose (p = 0.043), OGTT 30 min Δinsulin (p = 0.01) and AIR (p = 0.037). There was no evidence for an association with the rate of change in beta cell compensation for insulin resistance. CONCLUSIONS/INTERPRETATION: We conclude that variation in MTNR1B contributes to the absolute level of insulin secretion but not to differences in the temporal rate of change in insulin secretion. The observed association with the rate of change in insulin secretion reflects the natural physiological response to changes in underlying insulin sensitivity and is not a direct effect of the variant.


Assuntos
Diabetes Gestacional/genética , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Americanos Mexicanos/genética , Polimorfismo de Nucleotídeo Único , Receptor MT2 de Melatonina/genética , Adulto , Glicemia/metabolismo , Estudos Transversais , Diabetes Gestacional/metabolismo , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Teste de Tolerância a Glucose , Humanos , Resistência à Insulina/genética , Masculino , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
18.
Arterioscler Thromb Vasc Biol ; 34(6): 1307-13, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24675659

RESUMO

OBJECTIVE: Elevated levels of plasma trimethylamine N-oxide (TMAO), the product of gut microbiome and hepatic-mediated metabolism of dietary choline and L-carnitine, have recently been identified as a novel risk factor for the development of atherosclerosis in mice and humans. The goal of this study was to identify the genetic factors associated with plasma TMAO levels. APPROACH AND RESULTS: We used comparative genome-wide association study approaches to discover loci for plasma TMAO levels in mice and humans. A genome-wide association study in the hybrid mouse diversity panel identified a locus for TMAO levels on chromosome 3 (P=2.37 × 10(-6)) that colocalized with a highly significant (P=1.07 × 10(-20)) cis-expression quantitative trait locus for solute carrier family 30 member 7. This zinc transporter could thus represent 1 positional candidate gene responsible for the association signal at this locus in mice. A genome-wide association study for plasma TMAO levels in 1973 humans identified 2 loci with suggestive evidence of association (P=3.0 × 10(-7)) on chromosomes 1q23.3 and 2p12. However, genotyping of the lead variants at these loci in 1892 additional subjects failed to replicate their association with plasma TMAO levels. CONCLUSIONS: The results of these limited observational studies indicate that, at least in humans, genes play a marginal role in determining TMAO levels and that any genetic effects are relatively weak and complex. Variation in diet or the repertoire of gut microbiota may be more important determinants of plasma TMAO levels in mice and humans, which should be investigated in future studies.


Assuntos
Carnitina/metabolismo , Colina/metabolismo , Estudo de Associação Genômica Ampla , Metilaminas/sangue , Idoso , Animais , Proteínas de Transporte de Cátions/genética , Cromossomos Humanos Par 1 , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Família Multigênica , Oxigenases/genética , Polimorfismo de Nucleotídeo Único
19.
Hum Mol Genet ; 23(8): 2198-209, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24256810

RESUMO

Genome-wide association studies of colorectal cancer (CRC) have identified a number of common variants associated with modest risk, including rs3802842 at chromosome 11q23.1. Several genes map to this region but rs3802842 does not map to any known transcribed or regulatory sequences. We reasoned, therefore, that rs3802842 is not the functional single-nucleotide polymorphism (SNP), but is in linkage disequilibrium (LD) with a functional SNP(s). We performed ChIP-seq for histone modifications in SW480 and HCT-116 CRC cells, and incorporated ChIP-seq and DNase I hypersensitivity data available through ENCODE within a 137-kb genomic region containing rs3802842 on 11q23.1. We identified SNP rs10891246 in LD with rs3802842 that mapped within a bidirectional promoter region of genes C11orf92 and C11orf93. Following mutagenesis to the risk allele, the promoter demonstrated lower levels of reporter gene expression. A second SNP rs7130173 was identified in LD with rs3802842 that mapped to a candidate enhancer region, which showed strong unidirectional activity in both HCT-116 and SW480 CRC cells. The risk allele of rs7130173 demonstrated reduced enhancer activity compared with the common allele, and reduced nuclear protein binding affinity in electromobility shift assays compared with the common allele suggesting differential transcription factor (TF) binding. SNPs rs10891246 and rs7130173 are on the same haplotype, and expression quantitative trait loci (eQTL) analyses of neighboring genes implicate C11orf53, C11orf92 and C11orf93 as candidate target genes. These data imply that rs10891246 and rs7130173 are functional SNPs mapping to 11q23.1 and that C11orf53, C11orf92 and C11orf93 represent novel candidate target genes involved in CRC etiology.


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 11/genética , Neoplasias Colorretais/genética , Elementos Facilitadores Genéticos/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Luciferases/metabolismo , Repetições de Microssatélites/genética , Locos de Características Quantitativas , Fatores de Risco , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas
20.
Obesity (Silver Spring) ; 21(12): E790-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23804528

RESUMO

OBJECTIVE: Genetic variation in six genes has been associated with elevated liver fat and nonalcoholic fatty liver disease in adults. The influence of these genes on liver fat and whether a genetic risk score (GRS) would improve upon the ability of common clinical risk factors to predict elevated liver fat content (ELF) in Hispanic children was determined. DESIGN AND METHODS: 223 obese Hispanic children were genotyped for six SNPs. MRI was used to measure liver fat. A GRS was tested for association with ELF using multivariate linear regression. Predictors were assessed via ROC curves and pair-wise analysis was used to determine significance alone and combined with clinical markers. RESULTS: Only variants in PNPLA3 and APOC3 genes were associated with liver fat (P < 0.001, P = 0.01, respectively). Subjects with a GRS = 4 had ∼3-fold higher liver fat content than subjects with GRS of 0 (15.1 ± 12.7 vs. 5.1 ± 3.7%, P = 0.03). While the addition of the GRS to a model containing BMI and liver enzymes increased ROC AUC from 0.83 to 0.85 [95% CI, 0.79-0.89], (P = 0.01), it does not improve detection of ELF from a clinical perspective. CONCLUSIONS: Only PNPLA3 and APOC3 were related to ELF and a GRS comprised of these susceptibility alleles did not add to the discriminatory power of traditional biomarkers for clinical assessment of liver fat.


Assuntos
Fígado Gorduroso/genética , Hispano-Americanos/genética , Obesidade/genética , Sobrepeso/genética , Adolescente , Alanina Transaminase/sangue , Alelos , Antropometria , Apolipoproteína C-III/genética , Apolipoproteína C-III/metabolismo , Aspartato Aminotransferases/sangue , Glicemia/metabolismo , Composição Corporal , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Genótipo , Humanos , Lipase/genética , Lipase/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Hepatopatia Gordurosa não Alcoólica , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Triglicerídeos/metabolismo
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