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Introduction: Genetic or pharmacological inhibition of sphingolipid synthases prevented diabetes in animal studies. Scanty of cohort studies that examined circulating sphingolipids and incident diabetes yielded disparate findings. Hypothesis: Specific sphingolipids are associated with elevated risk of diabetes beyond traditional risk factors. Methods: Untargeted metabolomics profiling was performed using fasting serum samples collected from 2010 adult participants of the Hispanic Community Health Study/Study of Latinos, who were free of diabetes and other major chronic diseases at baseline (2008 to 2011). A total of 43 sphingolipids were quantified and 6 sphingolipid scores were derived considering subclasses and chemical structures. Survey Poisson regressions were applied to estimate relative risk (RR) and 95% confidence interval (CI) of incident diabetes associated with individual sphingolipids and the scores. Results: Over ~6 years of follow-up, 224 incident diabetes cases were identified using the ADA criteria. After adjustment for socioeconomic and lifestyle factors, 8 sphingolipids were associated with higher risk of diabetes significantly at the FDR-adjusted level ( Figure ). After further adjusting for general and central adiposity, blood pressure, CRP, HDL cholesterol, and triglycerides, only associations for three saturated sphingomyelins (SMs),36:0 (RR =1.41 [95% CI 1.17-1.69]), 38:0 (RR =1.32 [1.11-1.56]), and d18:0/22:0 (RR =1.45 [1.24-1.71]) remained. Of the 6 scores, only a score comprising 5 saturated SMs was associated with higher risk of diabetes (RR =1.31 [1.12-1.53]) after the full adjustment. An addition of the saturated SM score to the full model including traditional risk factor lead to a modest improvement in diabetes risk classification (net reclassification improvement = 22.0%; 95% CI: 7.8%-36.1%). Conclusions: Our findings suggest that a cluster of saturated SMs may be associated with higher risk of diabetes beyond traditional risk factors in US Hispanics/Latinos.

Introduction: Sedentary behavior is associated with cardiometabolic risk independent of physical activity, but the underlying mechanisms are not fully understood. Hypothesis: Sedentary behavior may influence serum metabolite profiles which are associated with cardiometabolic risk factors. Methods: The analyses included 2711 participants (43% men) of the HCHS/SOL aged 18 to 74 years, free of CVD and other major chronic diseases. Serum metabolomics was performed using an untargeted approach. Physical activity and sedentary behavior were measured by accelerometer (Actical) for a 7-day period. Survey linear regressions were used to examine associations between sedentary behavior and metabolites. Metabolite scores were calculated by summing up z-scores of significant metabolites within the same sub-pathway. Results: Of 624 known metabolites, 95 were significantly associated with sedentary behavior ( P Figure 1A ). The majority of significant metabolites were clustered into 7 sub-pathways. Three sub-pathway scores (branched-chain amino acids [BCAA], acylcarnitine and medium-chain fatty acid metabolism) were positively associated with sedentary behavior, while the other 4 sub-pathway scores (acylcholine, plasmalogen, nicotinate, and arginine) were inversely associated with sedentary behavior. Among these scores, the BCAA score showed unfavorable correlations with all cardiometabolic traits including obesity measures, glycemic traits, blood lipids and blood pressure. The acylcholine score showed favorable correlations with obesity measures and glycemic traits, though positive correlations with blood lipids were observed ( Figure 1B) . Conclusions: Our study identified multiple serum metabolites associated with sedentary behavior independent of physical activity, suggesting potential mechanistic links between sedentary behavior and cardiometabolic diseases.

Introduction: Several putative biomarkers of accelerated biological aging have been developed from patterns of DNA methylation in blood and other tissues (DNAm-Age scores). Some of these DNAm-Age scores have been found to be associated with age-related outcomes such as CVD and all-cause mortality, but their associations with frailty are unclear. We hypothesized that higher DNAm-Age scores measured in midlife are associated with higher odds of frailty and its components in late life. Methods: DNAm was measured at visit 2 or 3 in leukocyte DNA from 812 African American (AA) and 400 European American (EA) participants (mean age=54 years in AA, 57 years in EA), and was used to calculate three different DNAm-Age scores (Horvath, Hannum, and PhenoAge). Frailty status was assessed at visit 5, and dichotomized (frail/pre-frail or robust) using the following component criteria: slow walking speed, low grip strength, weight loss, low physical activity, and exhaustion. Logistic regression tested the associations of DNAm-Age scores, as the predictors of frailty status or each frailty component. Model 1 adjusted for visit 2 or 3 age, sex, education, white blood cell count, cell type proportions, and technical variables and model 2 additionally adjusted for BMI, smoking, alcohol, and visit 5 CHD, stroke, hypertension, and T2D. Inverse probability weights accounted for cohort attrition prior to frailty assessment. The Bonferroni-corrected threshold for statistical significance was set to p Results: In African American participants, a 4-year increase in the PhenoAge score in midlife was associated with frailty in late life (OR=1.21, 95% CI=1.09, 1.35, p=3E-4) in model 1, which was attenuated in model 2 (OR=1.13, 95% CI=1.02, 1.26, p=2.4E-2), and with physical activity (model 2 OR=1.32, 95% CI=1.13-1.53, p=4E-4); a 4-year increase in the Hannum score was associated with the exhaustion and grip strength components (OR=1.33, 95% CI=1.13-1.57, p=6E-4; OR=1.38, 95% CI=1.16-1.64, p=3E-4, respectively). In European American participants, the DNAm-Age scores were not associated with frailty however a 4-year increase in both the Horvath and Hannum scores was associated with the weight loss component (model 2 OR=1.56, 95% CI=1.20-2.02, p=9E-4; OR=2.37, 95% CI=1.49-3.76, p=2E-4), respectively. Conclusions: In African American ARIC participants, a higher mid-life PhenoAge score was associated with higher odds of frailty/pre-frailty in late life, consistent with accelerated biological aging, but was not significant after further adjustment. The Horvath, Hannum, and PhenoAge scores were associated with some frailty components in African American and European American ARIC participants, consistent with accelerated biological aging. Following replication, future studies should examine the causal relationship between DNAm-Age, frailty, and frailty components.

Introduction: Individuals with obesity are thought to be protected against some chronic disease as long as they do not incur metabolic health (MH) conditions. A new epigenetic biomarker of accelerated biological aging and health span, PhenoAge, was developed using DNA methylation (DNAm) markers. We hypothesized that obesity would be associated with higher PhenoAge than normal weight and overweight individuals only in the presence of MH conditions. Methods: DNAm was measured in leukocyte DNA for 2,454 African American participants (mean age=56.4 years) and used to calculate PhenoAge. BMI status was categorized as normal weight, overweight, and obese and MH was categorized by 0, 1, or at least 2 of the following: coronary heart disease, stroke, hypertension, type-2 diabetes, and hyperlipidemia. Linear regression tested the cross-sectional association of PhenoAge with BMI and MH, adjusting for sociodemographic variables, smoking, and technical variables. Stratified analyses by MH status were conducted to illustrate the statistical effects of BMI status in adults with and without MH conditions. Results: Participants with obesity had approximately 8 months higher PhenoAge compared to normal weight (β=0.68, 95% CI=0.21, 1.14, p=4.1E-3), and those with one (β=0.55, 95% CI=0.15, 0.94, p=6.4E-3) or at least 2 (β=0.81, 95% CI=0.38, 1.25, p=2E-4) MH conditions also had higher PhenoAge compared to those with 0 conditions. Figure 1 shows increments in PhenoAge with increments in number of MH conditions regardless of BMI. PhenoAge was significantly higher for obese compared to overweight for 0 and 1 MH conditions, but not compared to normal weight. Conclusions: In African American adults, both obesity status and presence of MH conditions were associated with a higher PhenoAge, suggesting metabolically healthy obesity is not entirely benign. Further phenotyping of the “metabolic health” obese condition is warranted to understand its relevance for healthspan.

Methylation levels measured at defined sites across the genome have recently been shown to be correlated with an individual’s chronological age. Age acceleration, or the difference between age estimated from DNA methylation status and chronological age, has been proposed as a novel biomarker of aging. In this study, the cross-sectional association between two different measures of age acceleration and cognitive function was investigated using whole blood samples from 2,157 African American participants 47–70 years of age in the population-based Atherosclerosis Risk in Communities (ARIC) Study. Cognition was evaluated using three domain-specific tests. A significant inverse association between a 1-year increase in age acceleration calculated using a blood-based age predictor and scores on the Word Fluency Test was found using a general linear model adjusted for chronological age, gender, and years of education (β = −0.140 words; p = .001) and after adding other potential confounding variables (β = −0.104 words, p = .023). The results were replicated in 1,670 European participants in the Generation Scotland: Scottish Family Health Study (fully adjusted model: β = −0.199 words; p = .034). A significant association was also identified in a trans-ethnic meta-analysis across cohorts that included an additional 708 European American ARIC study participants (fully adjusted model: β = −0.110 words, p = .003). There were no associations found using an estimate of age acceleration derived from multiple tissues. These findings provide evidence that age acceleration is a correlate of performance on a test of verbal fluency in middle-aged adults.

Mitochondrial DNA (mtDNA) is present in multiple copies in human cells. We evaluated cross-sectional associations of whole blood mtDNA copy number (CN) with several cardiometabolic disease traits in 408,361 participants of multiple ancestries in TOPMed and UK Biobank. Age showed a threshold association with mtDNA CN: among younger participants (

Here we examine the association between DNA methylation in circulating leukocytes and blood lipids in a multi-ethnic sample of 16,265 subjects. We identify 148, 35, and 4 novel associations among Europeans, African Americans, and Hispanics, respectively, and an additional 186 novel associations through a trans-ethnic meta-analysis. We observe a high concordance in the direction of effects across racial/ethnic groups, a high correlation of effect sizes between high-density lipoprotein and triglycerides, a modest overlap of associations with epigenome-wide association studies of other cardio-metabolic traits, and a largely non-overlap with lipid loci identified to date through genome-wide association studies. Thirty CpGs reached significance in at least 2 racial/ethnic groups including 7 that showed association with the expression of an annotated gene. CpGs annotated to CPT1A showed evidence of being influenced by triglycerides levels. DNA methylation levels of circulating leukocytes show robust and consistent association with blood lipid levels across multiple racial/ethnic groups.

AimsSudden cardiac death (SCD) is a major public health burden. Mitochondrial dysfunction has been implicated in a wide range of cardiovascular diseases including cardiomyopathy, heart failure, and arrhythmias, but it is unknown if it also contributes to SCD risk. We sought to examine the prospective association between mtDNA copy number (mtDNA-CN), a surrogate marker of mitochondrial function, and SCD risk.Methods and ResultsWe measured baseline mtDNA-CN in 11,093 participants from the Atherosclerosis Risk in Communities (ARIC) study. mtDNA-CN was calculated from probe intensities of mitochondrial single nucleotide polymorphisms (SNP) on the Affymetrix Genome-Wide Human SNP Array 6.0. SCD was defined as a sudden pulseless condition presumed due to a ventricular tachyarrhythmia in a previously stable individual without evidence of a non-cardiac cause of cardiac arrest. SCD cases were reviewed and adjudicated by an expert committee. During a median follow-up of 20.4 years, we observed 361 SCD cases. After adjusting for age, race, sex, and center, the hazard ratio (HR) for SCD comparing the 1st to the 5th quintiles of mtDNA-CN was 2.24 (95% CI 1.58 to 3.19; p-trend ConclusionIn this community-based prospective study, mtDNA-CN in peripheral blood was inversely associated with the risk of SCD.

Hundreds of loci have been associated with blood pressure traits from many genome-wide association studies. We identified an enrichment of these loci in aorta and tibial artery expression quantitative trait loci in our previous work in ∼100,000 Genetic Epidemiology Research on Aging (GERA) study participants. In the present study, we subsequently focused on determining putative regulatory regions for these and other tissues of relevance to blood pressure, to both fine-map these loci by pinpointing genes and variants of functional interest within them, and to identify any novel genes.We constructed maps of putative cis-regulatory elements using publicly available open chromatin data for the heart, aorta and tibial arteries, and multiple kidney cell types. Sequence variants within these regions may be evaluated quantitatively for their tissue- or cell-type-specific regulatory impact using deltaSVM functional scores, as described in our previous work. In order to identify genes of interest, we aggregate these variants in these putative cis-regulatory elements within 50Kb of the start or end of genes considered as “expressed” in these tissues or cell types using publicly available gene expression data, and use the deltaSVM scores as weights in the well-known group-wise sequence kernel association test (SKAT). We test for association with both blood pressure traits as well as expression within these tissues or cell types of interest, and identify several genes, includingMTHFR,C10orf32,CSK,NOV,ULK4,SDCCAG8,SCAMP5,RPP25,HDGFRP3,VPS37B, andPPCDC. Although our study centers on blood pressure traits, we additionally examined two known genes,SCN5AandNOS1APinvolved in the cardiac trait QT interval, in the Atherosclerosis Risk in Communities Study (ARIC), as a positive control, and observed an expected heart-specific effect. Thus, our method may be used to identify variants and genes for further functional testing using tissue- or cell-type-specific putative regulatory information.Author SummarySequence change in genes (“variants”) are linked to the presence and severity of different traits or diseases. However, as genes may be expressed in different tissues and at different times and degrees, using this information is expected to more accurately identify genes of interest. Variants within the genes are essential, but also in the sequences (“regulatory elements”) that control the genes’ expression in different tissues or cell types. In this study, we aim to use this information about expression and variants potentially involved in gene expression regulation to better pinpoint genes and variants in regulatory elements of interest for blood pressure regulation. We do so by taking advantage of such data that are publicly available, and use methods to combine information about variants in aggregate within a gene’s putative regulatory elements in tissues thought to be relevant for blood pressure, and identify several genes, meant to enable experimental follow-up.

We conducted a methylome-wide association study to examine associations between DNA methylation in whole blood and central adiposity and body fat distribution, measured as waist circumference, waist- to-hip ratio, and waist-to-height ratio adjusted for body mass index, in 2684 African American adults in the Atherosclerosis Risk in Communities study. We validated significantly associated Cytosine-phosphate-Guanine methylation sites (CpGs) among adults using the Women’s Health Initiative and Framingham Heart Study participants (combined N=5743) and generalized associations in adolescents from The Raine Study (N=820). We identified 11 CpGs that were robustly associated with one or more central adiposity trait in adults and 2 in adolescents, including CpG site associations near TXNIP, ADCY7, SREBF1, and RAP1GAP2 that had not previously been associated with obesity-related traits.

Impaired mitochondrial function has been implicated as a mechanism of doxorubicin-induced cardiotoxicity, however the precise genes that regulate this process in human cardiomyocytes remain to be elucidated. We hypothesized that doxorubicin significantly alters expression of genes involved in mitochondrial function in human cardiomyocytes, which in turn impairs mitochondrial respiration. Towards this, we treated human inducible pluripotent stem cell (iPSC)-cardiomyocytes with doxorubicin at 15 different time and dose conditions. Gene expression was assessed by RNAseq for each condition and 169 genes involved in mitochondrial function were analyzed for differential expression between control and treated conditions. Mitochondrial respiration (basal respiration, ATP production, maximal respiration, and spare respiratory capacity) was measured using the Seahorse Bioscience XFe96 Cell Mito Stress Test kit and correlated to gene expression levels. Of the 169 genes analyzed, 25 were significantly differentially expressed (P < 0.05) including GPX4 (P = 5.70 x 10 -3 ). Expression of GPX4 remained significant in pairwise comparisons by dose for day 2 and qRT-PCR validation confirmed a dose-dependent decrease in GPX4 expression. Maximal respiration (r = -0.62; P = 0.031) and spare respiratory capacity (r = -0.67; P = 0.017) correlated with GPX4 expression in doxorubicin-treated iPSC-cardiomyocytes. GPX4 encodes a glutathione peroxidase that is responsible for protecting the cell against oxidative damage. Damage due to reactive oxygen species (ROS) is one of the established mechanisms of anthracycline-induced cardiac damage. Our findings underscore a role for mitochondrial function and ROS in the development of doxorubicin-induced cardiotoxicity and implicates GPX4 in this process. The assessment of doxorubicin-altered gene expression in iPSC-cardiomyocytes may provide insight into how impaired mitochondrial respiration leads to cardiotoxicity and heart failure in cancer survivors treated with doxorubicin and other anthracyclines.

Background: The prevalence of cerebral small vessel disease (CSVD) and its associated complication of cognitive decline is significantly higher amongst African Americans than non-Hispanic Whites. Sickle cell anemia or sickle cell disease has been associated with a 30-45% increased prevalence of CSVD which presents as silent cerebral infarcts and impaired cognitive function. However, the association between sickle cell trait (heterozygosity for the sickle cell mutation) and cognitive decline or dementia has not been reported. Hypothesis: African Americans with SCT will have a significantly higher incidence and prevalence of cognitive impairment and dementia compared to those without SCT. Methods: We studied African Americans participants enrolled in the community-based prospective Atherosclerosis Risk in Communities (ARIC) study. SCT genotype status was determined using Taqman® genotyping from blood samples collected at baseline. Data from cognitive assessments at visits 2, 4 and 5, and an MRI performed at visit 5 were used for analysis. Using linear regression models for visit 2 cognitive measures and visit 5 brain MRI outcomes, a generalized estimating equation (GEE) for cognitive change, and Cox models for the incidence of dementia, we determined whether SCT was associated with a higher risk for cognitive dysfunction, global and regional brain volumes, and dementia. Results: Distribution of traditional risk factors for cognitive decline were not significantly different between participants with SCT (N = 176) and those without SCT (N = 2,532). In multivariable, cross-sectional analyses of 2,708 participants, those participants with SCT compared to those without SCT did not show a statistically significant difference in the global or domain-specific cognitive function scores at baseline. Participants with SCT did not experience a faster 20-year cognitive decline compared to participants without SCT. Also, participants with SCT had larger parietal cortical volume (100.5 cm3 vs. 97.9 cm3, diff. = 2.67 (0.24, 5.11) cm3, p = 0.03), and lower incidence of dementia (HR = 0.63 95% CI = 0.38, 1.05) compared to those without SCT. Participants with a co-inheritance of the apolipoprotein E (APOE) ε4 risk allele and SCT (N = 63) had worse scores on the digit symbol substitution test (DSST) at baseline (z-score = -0.08 (-0.26, 0.09), Pinteraction = 0.05) and over time (z-score = -0.12 (-0.38, 0.14), Pinteraction = 0.04), compared to those with the APOE ε4 risk allele who do not have SCT (N = 113). SCT was associated with 2-fold increased risk of dementia among participants with diabetes mellitus and a 55% reduction in risk of dementia among those without diabetes mellitus (Pinteraction = 0.01). Conclusions: SCT was not an independent risk factor for prevalent or incident cognitive decline, but it could potentially interact with and modify other risk factors for dementia and cognitive dysfunction. Disclosures Key: UniQure BV: Research Funding.

BackgroundMitochondrial DNA copy number (mtDNA-CN) has been associated with a variety of aging-related diseases, including all-cause mortality. However, the mechanism by which mtDNA-CN influences disease is not currently understood. One such mechanism may be through regulation of nuclear gene expression via the modification of nuclear DNA (nDNA) methylation.MethodsTo investigate this hypothesis, we assessed the relationship between mtDNA-CN and nDNA methylation in 2,507 African American (AA) and European American (EA) participants from the Atherosclerosis Risk in Communities (ARIC) study. To validate our findings we assayed an additional 2,528 participants from the Cardiovascular Health Study (CHS) (N=533) and Framingham Heart Study (FHS) (N=1,995). We further assessed the effect of experimental modification of mtDNA-CN through knockout of TFAM, a regulator of mtDNA replication, via CRISPR-Cas9.ResultsThirty-four independent CpGs were associated with mtDNA-CN at genome-wide significance (P-8). Meta-analysis across all cohorts identified six mtDNA-CN associated CpGs at genome-wide significance (P-8). Additionally, over half of these CpGs were associated with phenotypes known to be associated with mtDNA-CN, including coronary heart disease, cardiovascular disease, and mortality. Experimental modification of mtDNA-CN demonstrated that modulation of mtDNA-CN directly drives changes in nDNA methylation and gene expression of specific CpGs and nearby transcripts. Strikingly, the ‘neuroactive ligand receptor interaction’ KEGG pathway was found to be highly overrepresented in the ARIC cohort (P= 5.24×10-12), as well as the TFAM knockout methylation (P=4.41×10-4) and expression (P=4.30×10-4) studies.ConclusionsThese results demonstrate that changes in mtDNA-CN influence nDNA methylation at specific loci and result in differential expression of specific genes that may impact human health and disease via altered cell signaling.

Environmental exposure to lead (Pb), mercury (Hg), arsenic (As), cadmium (Cd), manganese (Mn), and aluminum (Al) has been associated with neurodevelopmental disorders including autism spectrum disorder (ASD). We conducted a pilot study during May 2015&ndash, May 2107 to estimate blood concentrations of six metals (Pb, Hg, As, Cd, Mn, and Al) and identify their associated factors for children with ASD or suspected of having ASD in Romania. Sixty children, age 2&ndash, 8 years, were administered versions of ADOS or ADI-R translated from English to Romanian. After assessment, 2&ndash, 3 mL of blood was obtained and analyzed for the concentrations of the six metals. The mean age of children was 51.9 months and about 90% were male. More than half (65%) of the children were born in Bucharest. Over 90% of concentrations of As and Cd were below limits of detection. Geometric mean concentrations of Pb, Mn, Al, and Hg were 1.14 &mu, g/dL, 10.84 &mu, g/L, 14.44 &mu, g/L, and 0.35 &mu, g/L, respectively. Multivariable linear regression analysis revealed that children who were female, had less educated parents, exhibited pica, and ate cold breakfast (e.g., cereal), watermelon, and lamb had significantly higher concentrations of Pb compared to their respective referent categories (all p &lt, 0.05 except for eating lamb, which was marginally significant, p = 0.053). Although this is the first study that provides data on concentrations of the six metals for Romanian children with ASD, the findings from this study could be useful for designing future epidemiologic studies for investigating the role of these six metals in ASD in Romanian children.

The rationale for genome-wide association study (GWAS) results is sequence variation in cis -regulatory elements (CREs) modulating a target gene’s expression as the major cause of trait variation. To understand the complete molecular landscape of one of these GWAS loci, we performed in vitro reporter screens in cardiomyocyte cell lines for CREs overlapping nearly all common variants associated with any of five independent QT interval (QTi)-associated GWAS hits at the SCN5A - SCN10A locus. We identified 13 causal CRE variants using allelic reporter activity, cardiomyocyte nuclear extract-based binding assays, overlap with human cardiac tissue DNaseI hypersensitive regions, and predicted impact of sequence variants on DNaseI sensitivity. Our analyses identified at least one high-confidence causal CRE variant for each of the five sentinel hits that could collectively predict SCN5A cardiac gene expression and QTi association. Although all 13 variants could explain SCN5A gene expression, the highest statistical significance was obtained with seven variants (inclusive of the five above). Thus, multiple, causal, mutually associated CRE variants can underlie GWAS signals.

Introduction: DNA methylation age acceleration (DNAmAA) scores, which are epigenetic biomarkers of aging and physiological responses to environmental factors such as lifestyle and health behaviors, have been previously shown to be associated with cardiovascular disease (CVD) outcomes and all-cause mortality. Life’s Simple 7 (LS7) is a tool promoted by the American Heart Association that summarizes individual adherence to seven key cardiovascular health and lifestyle metrics. We hypothesized that greater LS7 adherence would be associated with lower DNAmAA, consistent with slower biological aging. Methods: Associations between DNAmAA and LS7 were estimated separately in 2,312 African American (AA) and 1,036 European American (EA) adult participants in the Atherosclerosis Risk in Communities (ARIC) study. Visit 1 (mean age = 53 yrs in AA adults, 56 yrs in EA adults) LS7 was calculated for each participant, with 0, 1, or 2 points assigned by adherence to each component: smoking status, body mass index, physical activity, diet, plasma cholesterol, blood pressure, and fasting glucose . The summed score was categorized as inadequate (0-4), intermediate (5-9), or ideal (10-14) LS7 status. Three different previously published DNAmAA scores (Horvath, Hannum, and PhenoAge), were calculated using data from the Illumina HM450K BeadChip on stored frozen leukocytes available at visit 2 or 3 (approximately 3-6 years later). Linear regression models tested the association of LS7 category with DNAm scores, adjusting for sex, chronological age, education, income, study center, alcohol use , white blood cell count , imputed WBC type proportions using the Houseman method, Illumina HumanExome Beadchip principal components for genetic ancestry , and Illumina HM450K control probe principal components for technical adjustment. The Bonferonni-corrected threshold for statistical significance across the six tests was set to p Results: Among AA adults, ideal LS7 status (compared to poor status) was associated with a 1 year lower PhenoAge acceleration (β=-1.03; 95%CI=-1.70, -0.35; p=0.003), but was not significantly associated with Horvath or Hannum DNAmAA scores. In EA adults, ideal LS7 adherence was not significantly associated with any of the three DNAmAA scores, but the direction and magnitude of the PhenoAge acceleration association in EA was similar to that in AA (β=-0.96; 95%CI=-2.66, 0.73; p=0.27). Conclusions: African American adults with ideal LS7 status had lower PhenoAge acceleration than African Americans who did not, suggesting that heart-healthy lifestyles may slow biological aging processes in this population. Future studies should examine the prospective associations of changes in healthy lifestyle and changes in epigenetic biomarkers of aging as well as modifiers of this relationship.

Acute aortic dissections are a preventable cause of sudden death if individuals at risk are identified and surgically repaired in a non-emergency setting. Although mutations in single genes can be used to identify at-risk individuals, the majority of dissection case subjects do not have evidence of a single gene disorder, but rather have the other major risk factor for dissections, hypertension. Initial genome-wide association studies (GWASs) identified SNPs at the FBN1 locus associated with both thoracic aortic aneurysms and dissections. Here, we used the Illumina HumanExome array to genotype 753 individuals of European descent presenting specifically with non-familial, sporadic thoracic aortic dissection (STAD) and compared them to the genotypes of 2,259 control subjects from the Atherosclerosis Risk in Communities (ARIC) study matched for age, gender, and, for the majority of cases, hypertension. SNPs in FBN1, LRP1, and ULK4 were identified to be significantly associated with STAD, and these results were replicated in two independent cohorts. Combining the data from all cohorts confirmed an inverse association between LRP1 rs11172113 and STAD (p = 2.74 × 10(-8); OR = 0.82, 95% CI = 0.76-0.89) and a direct association between ULK4 rs2272007 and STAD (p = 1.15 × 10(-9); OR = 1.35, 95% CI = 1.23-1.49). Genomic copy-number variation analysis independently confirmed that ULK4 deletions were significantly associated with development of thoracic aortic disease. These results indicate that genetic variations in LRP1 and ULK4 contribute to risk for presenting with an acute aortic dissection.

Hematologic measures such as hematocrit and white blood cell (WBC) count are heritable and clinically relevant. We analyzed erythrocyte and WBC phenotypes in 52,531 individuals (37,775 of European ancestry, 11,589 African Americans, and 3,167 Hispanic Americans) from 16 population-based cohorts with Illumina HumanExome BeadChip genotypes. We then performed replication analyses of new discoveries in 18,018 European-American women and 5,261 Han Chinese. We identified and replicated four new erythrocyte trait-locus associations (CEP89, SHROOM3, FADS2, and APOE) and six new WBC loci for neutrophil count (S1PR4), monocyte count (BTBD8, NLRP12, and IL17RA), eosinophil count (IRF1), and total WBC count (MYB). The association of a rare missense variant in S1PR4 supports the role of sphingosine-1-phosphate signaling in leukocyte trafficking and circulating neutrophil counts. Loss-of-function experiments for S1pr4 in mouse and s1pr4 in zebrafish demonstrated phenotypes consistent with the association observed in humans and altered kinetics of neutrophil recruitment and resolution in response to tissue injury.

Mitochondrial dysfunction in kidney cells has been implicated in the pathogenesis of CKD. Mitochondrial DNA (mtDNA) copy number is a surrogate measure of mitochondrial function, and higher mtDNA copy number in peripheral blood has been associated with lower risk of two important risk factors for CKD progression, diabetes and microalbuminuria. We evaluated whether mtDNA copy number in peripheral blood associates with incident CKD in a population-based cohort of middle-aged adults. We estimated mtDNA copy number using 25 high-quality mitochondrial single nucleotide polymorphisms from the Affymetrix 6.0 array. Among 9058 participants, those with higher mtDNA copy number had a lower rate of prevalent diabetes and lower C-reactive protein levels and white blood cell counts. Baseline eGFR did not differ significantly by mtDNA copy number. Over a median follow-up of 19.6 years, 1490 participants developed CKD. Higher mtDNA copy number associated with lower risk of incident CKD (highest versus lowest quartile: hazard ratio 0.65; 95% confidence interval, 0.56 to 0.75; P

Background Exposure to many environmental chemicals, including metals, often does not occur in isolation, hence requires assessment of the associations between exposure to mixtures of chemicals and human health. Objectives To investigate associations of a metal mixture of lead (Pb), mercury (Hg), arsenic (As), cadmium (Cd), manganese (Mn), and aluminum (Al) in children with autism spectrum disorder (ASD), additively or interactively with each of three glutathione S-transferase (GST) genes (GSTP1, GSTT1, and GSTM1). Method Using data from 266 case-control pairs of Jamaican children (2–8 years old), we fitted negative and positive generalized weighted quantile sum (gWQS) regression models to assess the aforementioned associations. Results Based on additive and interactive negative gWQS models adjusted for maternal age, parental education, child’s parish, and seafood consumption, we found inverse associations of the overall mixture score with ASD [MOR (95 % CI) = 0.70 (0.49, 0.99); P Conclusions Differences in diet between ASD and control groups may play a role in the inverse associations we found. The possible interactive association between Mn and GSTP1 in ASD based on gWQS is consistent with our previous reports. However, possible interaction of GSTP1 with Pb and Hg in ASD requires further investigation and replication.

BACKGROUND: We previously reported a significant interactive association between polymorphisms of GSTP1 and blood manganese concentrations (BMC) with autism spectrum disorder (ASD) in Jamaican children. In this paper, we investigate the same interactive association with ASD while adjusting for the mixture of four metals (lead, mercury, cadmium, and arsenic). METHOD: We used data from 163 case-control pairs of children 2–8 years of age from our autism project in Jamaica, in which we collected blood for heavy metals analysis at enrollment. To minimize potential multicollinearity between concentrations of the four metals, we generated a mixture index using generalized weighted quantile sum regression, which was used in conditional logistic regression models to control for the four metals while assessing the interactive association between GSTP1 and BMC with ASD. RESULTS: Similar to the findings we reported previously, we found that in co-dominant and dominant models for GSTP1, among children with the Ile/Ile genotype, those with BMC > 12μg/L had 4.6 and 4.27 times higher odds of ASD compared to those with BMC < 12μg/L (adjusted Matched Odds Ratio (MOR) = 4.6, 95% CI: 1.21 – 17.42 and adjusted MOR = 4.27, 95% CI: 1.15 – 15.85, respectively). In the co-dominant model, for children with the Ile/Val and Val/Val genotypes, the adjusted MORs were 1.26 (95% CI: 0.32, 5.01) and 0.26 (95% CI: 0.05, 1.42), respectively. CONCLUSIONS: After adjusting for the mixture of four metals, the interactive association of BMC and GSTP1 with ASD remained significant with similar magnitude of associations. Results should be interpreted cautiously.

A weighted quantile sum (WQS) regression has been used to assess the associations between environmental exposures and health outcomes. However, the currently available WQS approach, which is based on additive effects, does not allow exploring for potential interactions of exposures with other covariates in relation to a health outcome. In addition, the current WQS cannot account for clustering, thus it may not be valid for analysis of clustered data. We propose a generalized WQS approach that can assess interactions by estimating stratum-specific weights of exposures in a mixture, while accounting for potential clustering effect of matched pairs of cases and controls as well as censored exposure data due to being below the limits of detection. The performance of the proposed method in identifying interactions is evaluated through simulations based on various scenarios of correlation structures among the exposures and with an outcome. We also assess how well the proposed method performs in the presence of the varying levels of censoring in exposures. Our findings from the simulation study show that the proposed method outperforms the traditional WQS, as indicated by higher power of detecting interactions. We also find no strong evidence that the proposed method falsely identifies interactions when there are no true interactive effects. We demonstrate application of the proposed method to real data from the Epidemiological Research on Autism Spectrum Disorder (ASD) in Jamaica (ERAJ) by examining interactions between exposure to manganese and glutathione S-transferase family gene, GSTP1 in relation to ASD.

Supplemental Digital Content is available in the text, Rare variants, in particular renal salt handling genes, contribute to monogenic forms of hypertension and hypotension syndromes with electrolyte abnormalities. A study by Ji et al (2008) demonstrated this effect for rare loss-of-function coding variants in SLC12A3 (NCCT), SLC12A1 (NKCC2), and KCNJ1 (ROMK) that led to reduction of ∼6 mm Hg for SBP and ∼3 mm Hg for DBP among carriers in 2492 European ancestry Framingham Heart Study (FHS) subjects. These findings support a potentially large role for these variants in interindividual variation in systolic and diastolic blood pressure (SBP, DBP) in the population. The present study focuses on replicating the analyses completed by Ji et al to identify effects of rare variants in the population-based Atherosclerosis Risk in Communities (ARIC) study. We attempted to replicate the findings by Ji et al by applying their criteria to identify putative loss-of-function variants with allele frequency

Identification of coding variant associations for complex diseases offers a direct route to biological insight, but is dependent on appropriate inference concerning the causal impact of those variants on disease risk. We aggregated coding variant data for 81,412 type 2 diabetes (T2D) cases and 370,832 controls of diverse ancestry, identifying 40 distinct coding variant association signals (at 38 loci) reaching significance (p−7). Of these, 16 represent novel associations mapping outside known genome-wide association study (GWAS) signals. We make two important observations. First, despite a threefold increase in sample size over previous efforts, only five of the 40 signals are driven by variants with minor allele frequency 1.29. Second, we used GWAS data from 50,160 T2D cases and 465,272 controls of European ancestry to fine-map these associated coding variants in their regional context, with and without additional weighting to account for the global enrichment of complex trait association signals in coding exons. At the 37 signals for which we attempted fine-mapping, we demonstrate convincing support (posterior probability >80% under the “annotation-weighted” model) that coding variants are causal for the association at 16 (including novel signals involving POC5 p.His36Arg, ANKH p.Arg187Gln, WSCD2 p.Thr113Ile, PLCB3 p.Ser778Leu, and PNPLA3 p.Ile148Met). However, at 13 of the 37 loci, the associated coding variants represent “false leads” and naïve analysis could have led to an erroneous inference regarding the effector transcript mediating the signal. Accurate identification of validated targets is dependent on correct specification of the contribution of coding and non-coding mediated mechanisms at associated loci.

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder with poorly understood etiology. Many maternal exposures during pregnancy and breastfeeding potentially interfere with neurodevelopment. Using data from two age- and sex-matched case-control studies in Jamaica (n = 298 pairs), results of conditional logistic regression analyses suggest that maternal exposures to fever or infection (matched odds ratio (MOR) = 3.12, 95% CI: 1.74 – 5.60), physical trauma (MOR = 2.02, 95% CI: 1.01 – 4.05), and oil-based paints (MOR = 1.99, 95% CI: 1.14 – 3.46) may be associated with ASD. Additionally, maternal exposure to oil-based paints may modify the relationship between maternal exposure to pesticides and ASD, which deepens our understanding of the association between pesticides and ASD.

Genome-wide association studies (GWAS) have identified >250 loci for body mass index (BMI), implicating pathways related to neuronal biology. Most GWAS loci represent clusters of common, noncoding variants from which pinpointing causal genes remains challenging. Here we combined data from 718,734 individuals to discover rare and low-frequency (minor allele frequency (MAF) < 5%) coding variants associated with BMI. We identified 14 coding variants in 13 genes, of which 8 variants were in genes (ZBTB7B, ACHE, RAPGEF3, RAB21, ZFHX3, ENTPD6, ZFR2 and ZNF169) newly implicated in human obesity, 2 variants were in genes (MC4R and KSR2) previously observed to be mutated in extreme obesity and 2 variants were in GIPR. The effect sizes of rare variants are ~10 times larger than those of common variants, with the largest effect observed in carriers of an MC4R mutation introducing a stop codon (p.Tyr35Ter, MAF = 0.01%), who weighed ~7 kg more than non-carriers. Pathway analyses based on the variants associated with BMI confirm enrichment of neuronal genes and provide new evidence for adipocyte and energy expenditure biology, widening the potential of genetically supported therapeutic targets in obesity.

Depressive symptoms independently contribute to major adverse coronary events (MACEs), with the biological immune response to depression being a likely mediator of this relationship. To determine whether genetic- and/or gender-specific phenotypic differences contribute to associations among depressive symptoms, inflammatory response, and risk of MACE in patients with acute coronary syndrome (ACS), we conducted a prospective study of 1,117 ACS patients to test a gender-specific model in which depressive symptoms (Beck Depression Inventory-II [BDI-II]) are associated with risk of MACE. Cox proportional hazards models were used to model time to incident MACE and determine whether single-nucleotide polymorphisms (SNPs) in specific inflammatory protein-coding genes and depressive symptoms interact to influence levels of inflammatory proteins or risk of MACE. Females had significantly higher high-sensitivity C-reactive protein and monocyte chemoattractant protein-1 levels. Depression status differed by gender (29.9% of females and 21.1% of males had BDI-II scores indicative of depression [ p = .0014]). Depressive symptoms were associated with MACE; however, the interaction between these symptoms and gender was not significant. SNPs and depressive symptoms did not interact to influence inflammation or MACE. More females than males had BDI-II scores indicative of depression, yet the association between positive depressive symptom status and MACE did not vary by gender. Nor did the SNPs interact with depressive symptoms to influence inflammation or MACE. It remains of interest to identify a high-risk subgroup of ACS patients with genetic polymorphisms that result in immunoinflammatory dysregulation in the presence of depressive symptoms.

Background We conducted an epigenome-wide association study (EWAS) on obesity in healthy youth and young adults and further examined to what extent identified signals influenced gene expression and were independent of cell type composition and obesity-related cardio-metabolic risk factors. Genome-wide DNA methylation data from leukocytes were obtained from 700 African Americans aged 14–36. We also measured genome-wide DNA methylation data from neutrophils as well as genome-wide gene expression data from leukocytes in a subset of samples (n = 188). Results The EWAS identified 76 obesity-related CpG sites in leukocytes with p

There is increasing evidence of a relationship between blood DNA methylation and body mass index (BMI). We aimed to assess associations of BMI with individual methylation measures (CpGs) through a cross-sectional genome-wide DNA methylation association study and a longitudinal analysis of repeated measurements over time. Using the Illumina Infinium HumanMethylation450 BeadChip, DNA methylation measures were determined in baseline peripheral blood samples from 5361 adults recruited to the Melbourne Collaborative Cohort Study (MCCS) and selected for nested case–control studies, 2586 because they were subsequently diagnosed with cancer (cases) and 2775 as controls. For a subset of 1088 controls, these measures were repeated using blood samples collected at wave 2 follow-up, a median of 11 years later; weight was measured at both time points. Associations between BMI and blood DNA methylation were assessed using linear mixed-effects regression models adjusted for batch effects and potential confounders. These were applied to cases and controls separately, with results combined through fixed-effects meta-analysis. Cross-sectional analysis identified 310 CpGs associated with BMI with P

Fibrinogen, coagulation factor VII (FVII), and factor VIII (FVIII) and its carrier von Willebrand factor (vWF) play key roles in hemostasis. Previously identified common variants explain only a small fraction of the trait heritabilities, and additional variations may be explained by associations with rarer variants with larger effects. The aim of this study was to identify low-frequency (minor allele frequency [MAF] >= 0.01 and < 0.05) and rare (MAF < 0.01) variants that influence plasma concentrations of these 4 hemostatic factors by meta-analyzing exome chip data from up to 76 000 participants of 4 ancestries. We identified 12 novel associations of low-frequency (n=2) andrare (n=10) variants across the fibrinogen, FVII, FVIII, and vWF traits that were independent of previously identified associations. Novel loci were found within previously reported genes and had effect sizes much larger than and independent of previously identified common variants. In addition, associations at KCNT1, HID1, and KATNB1 identified new candidate genes related to hemostasis for follow-up replication and functional genomic analysis. Newly identified low-frequency and rare-variant associations accounted for modest amounts of trait variance and therefore are unlikely to increase predicted trait heritability but provide new information for understanding individual variation in hemostasis pathways.

The common nonsynonymous variant rs16969968 in the α5 nicotinic receptor subunit gene (CHRNA5) is the strongest genetic risk factor for nicotine dependence in European Americans and contributes to risk in African Americans. To comprehensively examine whether other CHRNA5 coding variation influences nicotine dependence risk, we performed targeted sequencing on 1582 nicotine-dependent cases (Fagerstrom Test for Nicotine Dependence score⩾4) and 1238 non-dependent controls, with independent replication of common and low frequency variants using 12 studies with exome chip data. Nicotine dependence was examined using logistic regression with individual common variants (minor allele frequency (MAF)⩾0.05), aggregate low frequency variants (0.05>MAF⩾0.005) and aggregate rare variants (MAF

The objective of this study was to characterize the concentrations of lead, mercury, cadmium, aluminum, and manganese in umbilical cord blood of Jamaican newborns and to explore the possible association between concentrations of these elements and certain birth outcomes. Based on data from 100 pregnant mothers and their 100 newborns who were enrolled from Jamaica in 2011, the arithmetic mean (standard deviation) concentrations of cord blood lead, mercury, aluminum, and manganese were 0.8 (1.3 μg/dL), 4.4 (2.4 μg/L), 10.9 (9.2 μg/L), and 43.7 (17.7 μg/L), respectively. In univariable General Linear Models, the geometric mean cord blood aluminum concentration was higher for children whose mothers had completed their education up to high school compared to those whose mothers had any education beyond high school (12.2 μg/L vs. 6.4 μg/L, p &lt, 0.01). After controlling for maternal education level and socio-economic status (through ownership of a family car), the cord blood lead concentration was significantly associated with head circumference (adjusted p &lt, 0.01). Our results not only provide levels of arsenic and the aforementioned metals in cord blood that could serve as a reference for the Jamaican population, but also replicate previously reported significant associations between cord blood lead concentrations and head circumference at birth in other populations.

We investigated the role of glutathione S-transferase (GST) genes in Autism Spectrum Disorder (ASD). We used data from 111 pairs of age- and sex-matched ASD cases and typically developing (TD) controls between 2-8 years of age from Jamaica to investigate the role of GST pi 1 (GSTP1), GST theta 1 (GSTT1), and GST mu 1 (GSTM1) polymorphisms in susceptibility to ASD. In univariable conditional logistic regression models we did not observe significant associations between ASD status and GSTT1, GSTM1, or GSTP1 genotype (all P > 0.15). However, in multivariable conditional logistic regression models, we identified a significant interaction between GSTP1 and GSTT1 in relation to ASD. Specifically, in children heterozygous for the GSTP1 Ile105Val polymorphism, the odds of ASD was significantly higher in those with the null GSTT1 genotype than those with the other genotypes [Matched Odds Ratio (MOR) = 2.97, 95% CI (1.09, 8.01), P = 0.03]. Replication in other populations is warranted.

International audience; 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.

Background: Over 90 regions of the genome have been associated with lung function to date, many of which have also been implicated in chronic obstructive pulmonary disease. Methods: We carried out meta-analyses of exome array data and three lung function measures: forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and the ratio of FEV1 to FVC (FEV1/FVC). These analyses by the SpiroMeta and CHARGE consortia included 60,749 individuals of European ancestry from 23 studies, and 7,721 individuals of African Ancestry from 5 studies in the discovery stage, with follow-up in up to 111,556 independent individuals. Results: We identified significant (P-7) associations with six SNPs: a nonsynonymous variant in RPAP1, which is predicted to be damaging, three intronic SNPs (SEC24C, CASC17 and UQCC1) and two intergenic SNPs near to LY86 and FGF10. Expression quantitative trait loci analyses found evidence for regulation of gene expression at three signals and implicated several genes, including TYRO3 and PLAU. Conclusions: Further interrogation of these loci could provide greater understanding of the determinants of lung function and pulmonary disease.

The administration requirements of the Autism Diagnostic Observation Schedule and the Autism Diagnostic Interview–Revised, widely used in high-income countries, make them less feasible for diagnosis of autism spectrum disorder in low- and middle-income countries. The flexible administration requirements of the Childhood Autism Rating Scale have resulted in its use in both high-income countries and low- and middle-income countries. This study examines the agreement between assessments using the Childhood Autism Rating Scale with those using the Autism Diagnostic Observation Schedule or Autism Diagnostic Observation Schedule, Second Edition and Autism Diagnostic Interview–Revised in Jamaica. Children aged 2–8 years (n = 149) diagnosed with autism by an experienced clinician using the Childhood Autism Rating Scale were re-evaluated using the Autism Diagnostic Observation Schedule and Autism Diagnostic Interview–Revised. The proportion diagnosed with autism spectrum disorder using the Autism Diagnostic Observation Schedule, Autism Diagnostic Observation Schedule, Second Edition, and Autism Diagnostic Interview–Revised was determined and mean domain scores compared using analysis of variance (ANOVA). The mean age was 64.4 (standard deviation = 21.6) months; the male:female ratio was 6:1. The diagnostic agreement of the Childhood Autism Rating Scale with the Autism Diagnostic Observation Schedule and Autism Diagnostic Observation Schedule, Second Edition was 100.0% and 98.0%, respectively. Agreement with the Autism Diagnostic Interview–Revised was 94.6%. Domain scores were highest for children with more severe symptoms (p

Intake of hemoglobin by the hemoglobin-haptoglobin receptor CD163 leads to a distinct alternative non-foam cell antiinflammatory macrophage phenotype that was previously considered atheroprotective. Here, we reveal an unexpected but important pathogenic role for these macrophages in atherosclerosis. Using human atherosclerotic samples, cultured cells, and a mouse model of advanced atherosclerosis, we investigated the role of intraplaque hemorrhage on macrophage function with respect to angiogenesis, vascular permeability, inflammation, and plaque progression. In human atherosclerotic lesions, CD163+ macrophages were associated with plaque progression, microvascularity, and a high level of HIF1α and VEGF-A expression. We observed irregular vascular endothelial cadherin in intraplaque microvessels surrounded by CD163+ macrophages. Within these cells, activation of HIF1α via inhibition of prolyl hydroxylases promoted VEGF-mediated increases in intraplaque angiogenesis, vascular permeability, and inflammatory cell recruitment. CD163+ macrophages increased intraplaque endothelial VCAM expression and plaque inflammation. Subjects with homozygous minor alleles of the SNP rs7136716 had elevated microvessel density, increased expression of CD163 in ruptured coronary plaques, and a higher risk of myocardial infarction and coronary heart disease in population cohorts. Thus, our findings highlight a nonlipid-driven mechanism by which alternative macrophages promote plaque angiogenesis, leakiness, inflammation, and progression via the CD163/HIF1α/VEGF-A pathway.

Background: Ischemic stroke is a heterogeneous trait and its genetic architecture is poorly understood. The genetic contribution may be stronger for stroke occurring at younger (vs. older) ages. To identify additional stroke susceptibility variants, we genotyped participants in the Genetics of Early Onset Stroke (GEOS) with the exome array and conducted association analyses with the goal of identifying functional risk variants by interrogating the protein-coding portion of genes. Methods: The GEOS Study was initiated as a biracial population-based study of cases with first-ever ischemic stroke 15 to 49 years of age (n=828) and matched controls (n=850). All participants underwent exome-chip genotyping. Logistic regression was used to calculate associations in European-Caucasians (EUR) and African-Americans (AA), and summary results were combined by meta-analysis. Results: Our analyses revealed four highly associated variants for all-stroke and several others that were stroke subtype specific. Among these for all-stroke, we identified a missense variant in VWDE (rs6460939 (K (AA G ) --> N (AA C )), which encodes the Von Willebrand Factor D and EGF domain-containing protein. This protein plays a role in intracellular calcium ion binding within a variety of cell-types. The association was present in both European-Caucasians (OR = 1.34, p = 0.002) and African-Americans (OR = 1.32, p = 0.01), and was strengthened in a meta-analysis of both ethnic groups (OR = 1.41, p = 8.95 х 10 -6 ). The frequency of the effect C allele was 0.46 in EUR and 0.55 in AA. Efforts in additional data sets to further replicate this association, and the others identified, are ongoing. Conclusion: Exome-based analyses in the setting of young-onset stroke is a productive methodology to identify genetic risk variants.

We screened DNA sequence variants on an exome-focused genotyping array in >300,000 participants with replication in >280,000 participants and identified 444 independent variants in 250 loci significantly associated with total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and/or triglycerides (TG). At two loci (JAK2 and A1CF), experimental analysis in mice revealed lipid changes consistent with the human data. We utilized mapped variants to address four clinically relevant questions and found the following: (1) beta-thalassemia trait carriers displayed lower TC and were protected from coronary artery disease; (2) outside of the CETP locus, there was not a predictable relationship between plasma HDL-C and risk for age-related macular degeneration; (3) only some mechanisms of lowering LDL-C seemed to increase risk for type 2 diabetes; and (4) TG-lowering alleles involved in hepatic production of TG-rich lipoproteins (e.g., TM6SF2, PNPLA3) tracked with higher liver fat, higher risk for type 2 diabetes, and lower risk for coronary artery disease whereas TG-lowering alleles involved in peripheral lipolysis (e.g., LPL, ANGPTL4) had no effect on liver fat but lowered risks for both type 2 diabetes and coronary artery disease.

Background The link between DNA methylation, obesity, and adiposity-related diseases in the general population remains uncertain. Methods and Findings We conducted an association study of body mass index (BMI) and differential methylation for over 400,000 CpGs assayed by microarray in whole-blood-derived DNA from 3,743 participants in the Framingham Heart Study and the Lothian Birth Cohorts, with independent replication in three external cohorts of 4,055 participants. We examined variations in whole blood gene expression and conducted Mendelian randomization analyses to investigate the functional and clinical relevance of the findings. We identified novel and previously reported BMI-related differential methylation at 83 CpGs that replicated across cohorts; BMI-related differential methylation was associated with concurrent changes in the expression of genes in lipid metabolism pathways. Genetic instrumental variable analysis of alterations in methylation at one of the 83 replicated CpGs, cg11024682 (intronic to sterol regulatory element binding transcription factor 1 [SREBF1]), demonstrated links to BMI, adiposity-related traits, and coronary artery disease. Independent genetic instruments for expression of SREBF1 supported the findings linking methylation to adiposity and cardiometabolic disease. Methylation at a substantial proportion (16 of 83) of the identified loci was found to be secondary to differences in BMI. However, the cross-sectional nature of the data limits definitive causal determination. Conclusions We present robust associations of BMI with differential DNA methylation at numerous loci in blood cells. BMI-related DNA methylation and gene expression provide mechanistic insights into the relationship between DNA methylation, obesity, and adiposity-related diseases., Daniel Levy and colleagues examine mechanisms that could link body mass index to cardiovascular diseases via gene expression., Author Summary Why Was This Study Done? Genetic sequence variants explain only a modest proportion of the variation in body mass index (BMI) and cardiometabolic disease in the general population. There is limited understanding of the link of DNA methylation—a well-characterized epigenetic modification—with BMI and cardiometabolic disease in the general population. What Did the Researchers Do and Find? We conducted a cross-sectional analysis of the association of BMI with leukocyte DNA methylation at over 400,000 sites in the genome among 7,798 community-dwelling adults. We identified associations between BMI and methylation at 83 replicated sites (including 50 novel sites) and concurrent differences in expression in whole blood of genes overrepresented in lipid metabolism pathways. Using genetic sequence variants to model exposure to differential DNA methylation and tissue-specific gene expression, we found differential methylation and expression of SREBF1 to be implicated in BMI, adiposity-related traits, and coronary artery disease. Using genetic sequence variants to model exposure to differences in BMI, we found a substantial proportion of the differentially methylated sites (16 of 83) to be downstream of BMI. What Do These Findings Mean? Evidence is accumulating that epigenetic modifications, such as DNA methylation, are related to obesity-related diseases in the general population. We provide support for a role of genomic regulation of a lipid metabolism transcription factor, SREBF1, in adiposity and coronary artery disease. Mendelian randomization approaches can help prioritize relevant loci for future functional studies, but the cross-sectional observational nature of our study limits definitive causal inference.

BackgroundIn older adults (aged 70-74 years), African-Americans have 4-fold higher risk of developing hypertension-attributed end-stage renal disease (ESRD) than European-Americans. A hypothesized mechanism linking hypertension and progressive chronic kidney disease (CKD) is the innate immune response and inflammation. Persons with CKD are also more susceptible to infection. Gene expression in peripheral blood can provide a view of the innate immune activation profile. We aimed to identify differentially expressed genes, microRNAs, and pathways in peripheral blood between cases with CKD and high blood pressure under hypertension treatment versus controls without CKD and with controlled blood pressure in African Americans.MethodsCase and control pairs (N = 15x2) were selected from those without diabetes and were matched for age, sex, body mass index, APOL1 risk allele count, and hypertension medication use. High blood pressure under hypertension treatment was defined as hypertension medication use and systolic blood pressure (SBP) ≥ 145 mmHg. CKD was defined as estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m2. Cases were selected from those with CKD and high blood pressure under hypertension treatment, and controls were selected from those without CKD (eGFR: 75-120 mL/min/1.73m2 and urine albumin-to-creatinine ratio < 30mg/g) and with blood pressure controlled by hypertension medication use (SBP < 135 mmHg and D(diastolic)BP < 90 mm Hg). We perform RNA sequencing of mRNA and microRNA and conducted differential expression and co-expression network analysis.ResultsOf 347 miRNAs included in the analysis, 14 were significantly associated with case status (Benjamini-Hochberg adjusted p-value [BH p] < 0.05). Of these, ten were downregulated in cases: three of each belong to the miR-17 and miR-15 families. In co-expression network analysis of miRNA, one module, which included 13 of the 14 significant miRNAs, had significant association with case status. Of the 14,488 genes and 41,739 transcripts included in the analysis, none had significant association with case status. Gene co-expression network analyses did not yield any significant associations for mRNA.ConclusionWe have identified 14 differentially expressed miRNAs in the peripheral blood of CKD cases with high blood pressure under hypertension treatment as compared to appropriate controls. Most of the significant miRNAs were downregulated and have critical roles in immune cell functions. Future studies are needed to replicate our findings and determine whether the downregulation of these miRNAs in immune cells may influence CKD progression or complications.

Hypertension is a major risk factor for all cardiovascular diseases, especially among African Americans. This study focuses on identifying specific blood pressure (BP) genes using 15 914 individuals of African ancestry from eight cohorts (Africa America Diabetes Mellitus, Atherosclerosis Risk in Communities Study, Coronary Artery Risk Development in young Adults, Genetics Network, Genetic Epidemiology Network of Arteriopathy, Howard University Family Study, Hypertension Genetic Epidemiology Network, and Loyola University Chicago Cohort) to further genetic findings in this population which has generally been underrepresented in BP studies. We genotyped and performed various single variant and gene-based exome-wide analyses on 15 914 individuals on the Illumina HumanExome Beadchip v1.0 or v1.1 to test association with SBP and DBP long-term average residuals that were adjusted for age, age-squared, sex, and BMI. We identified rare variants affecting SBP and DBP in 10 genes: AFF1, GAPDHS, SLC28A3, COL6A1, CRYBA2, KRBA1, SEL1L3, YOD1, CCDC13, and QSOX1. Prior experimental evidence for six of these 10 candidate genes supports their involvement in cardiovascular mechanisms, corroborating their potential roles in BP regulation. Although our results require replication or validation due to their low numbers of carriers, and an ethnicity-specific genotyping array may be more informative, this study, which has identified several candidate genes in this population most susceptible to hypertension, presents one of the largest African-ancestry BP studies to date and the largest including analysis of rare variants.

Arsenic is a toxic metalloid with known adverse effects on human health. Glutathione-S-transferase (GST) genes, including GSTT1, GSTP1, and GSTM1, play a major role in detoxification and metabolism of xenobiotics. We investigated the association between GST genotypes and whole blood arsenic concentrations (BASC) in Jamaican children with and without autism spectrum disorder (ASD). We used data from 100 ASD cases and their 1:1 age- and sex-matched typically developing (TD) controls (age 2–8 years) from Jamaica. Using log-transformed BASC as the dependent variable in a General Linear Model, we observed a significant interaction between GSTP1 and ASD case status while controlling for several confounding variables. However, for GSTT1 and GSTM1 we did not observe any significant associations with BASC. Our findings indicate that TD children who had the Ile/Ile or Ile/Val genotype for GSTP1 had a significantly higher geometric mean BASC than those with genotype Val/Val (3.67 µg/L vs. 2.69 µg/L, p < 0.01). Although, among the ASD cases, this difference was not statistically significant, the direction of the observed difference was consistent with that of the TD control children. These findings suggest a possible role of GSTP1 in the detoxification of arsenic.

© 2019 Cunningham et al. Background Hypertension (HTN) disproportionately affects African Americans (AAs), who respond better to thiazide diuretics than other antihypertensives. Variants of the APOL1 gene found in AAs are associated with a higher rate of kidney disease and play a complex role in cardiovascular disease. Methods AA subjects from four HTN trials (n = 961) (GERA1, GERA2, PEAR1, and PEAR2) were evaluated for blood pressure (BP) response based on APOL1 genotype after 4–9 weeks of monotherapy with thiazides, beta blockers, or candesartan. APOL1 G1 and G2 variants were determined by direct sequencing or imputation. Results Baseline systolic BP (SBP) and diastolic BP (DBP) levels did not differ based on APOL1 genotype. Subjects with 1–2 APOL1 risk alleles had a greater SBP response to candesartan (-12.2 +/- 1.2 vs -7.5 +/- 1.8 mmHg, p = 0.03; GERA2), and a greater decline in albuminuria with candesartan (-8.3 +/- 3.1 vs +3.7 +/- 4.3 mg/day, p = 0.02). APOL1 genotype did not associate with BP response to thiazides or beta blockers. GWAS was performed to determine associations with BP response to candesartan depending on APOL1 genotype. While no SNPs reached genome wide significance, SNP rs10113352, intronic in CSMD1, predicted greater office SBP response to candesartan (p = 3.7 x 10−7) in those with 1–2 risk alleles, while SNP rs286856, intronic in DPP6, predicted greater office SBP response (p = 3.2 x 10−7) in those with 0 risk alleles. Conclusions Hypertensive AAs without overt kidney disease who carry 1 or more APOL1 risk variants have a greater BP and albuminuria reduction in response to candesartan therapy. BP response to thiazides or beta blockers did not differ by APOL1 genotype. Future studies confirming this initial finding in an independent cohort are required. PEAR1 and PEAR2 was supported by a grant from the National Institutes of Health (https://www.nih.gov/), grant U01 GM074492, funded as part of the Pharmacogenetics Research Network (JAJ). PEAR1 was also supported by the following grants from the NIH National Center for Research Resources: grant M01 RR00082 and UL1 RR029890 to the University of Florida, grants UL1 RR025008 and M01 RR00039 (ABC) to Emory University, and UL1 RR024150 to Mayo Clinic. PEAR2 was also supported by the National Center for Advancing Translational Sciences under the award number UL1 TR000064 (University of Florida); UL1 TR000454 (Emory University) and UL1 TR000135 (Mayo Clinic), and the Mayo Foundation. GERA was supported by NIH grants HL74735, HL53330 (STT), and the Mayo Foundation (https://www.mayo.edu/research).

Low-frequency coding DNA sequence variants in the proprotein convertase subtilisin/kexin type 9 gene (PCSK9) lower plasma low-density lipoprotein cholesterol (LDL-C), protect against risk of coronary heart disease (CHD), and have prompted the development of a new class of therapeutics. It is uncertain whether the PCSK9 example represents a paradigm or an isolated exception. We used the "Exome Array" to genotype >200,000 low-frequency and rare coding sequence variants across the genome in 56,538 individuals (42,208 European ancestry [EA] and 14,330 African ancestry [AA]) and tested these variants for association with LDL-C, high-density lipoprotein cholesterol (HDL-C), and triglycerides. Although we did not identify new genes associated with LDL-C, we did identify four low-frequency (frequencies between 0.1% and 2%) variants (ANGPTL8 rs145464906 [c.361C>T; p.Gln121*], PAFAH1B2 rs186808413 [c.482C>T; p.Ser161Leu], COL18A1 rs114139997 [c.331G>A; p.Gly111Arg], and PCSK7 rs142953140 [c.1511G>A; p.Arg504His]) with large effects on HDL-C and/or triglycerides. None of these four variants was associated with risk for CHD, suggesting that examples of low-frequency coding variants with robust effects on both lipids and CHD will be limited.

We have shown previously that noncoding variants mapping around a specific set of 170 genes encoding cardiomyocyte intercalated disc (ID) proteins are more enriched for associations with QT interval than observed for genome-wide comparisons. At a false discovery rate (FDR) of 5%, we had identified 28 such ID protein-encoding genes. Here, we assessed whether coding variants at these 28 genes affect QT interval in the general population as well. We used exome sequencing in 4,469 European American (EA) and 1,880 African American (AA) ancestry individuals from the population-based ARIC (Atherosclerosis Risk In Communities) Study cohort to focus on rare (allele frequency TTN. Taken together with the mapping of a QT interval GWAS locus near TTN, our observation of rare deleterious coding variants in TTN associated with QT interval show that TTN plays a role in regulation of cardiac electrical conductance and coupling and is a risk factor for cardiac arrhythmias and sudden cardiac death.

Cerebral small vessel disease (SVD) is one of the most common degenerative vessel disorders of the aging brain. White matter hyperintensities (WMH) on magnetic resonance imaging (MRI) are viewed as typical markers of SVD and are associated with an increased risk of stroke, dementia, and death. Advancing age is the strongest predictor of WMH prevalence and severity. Recent studies have developed a novel biomarker of aging, termed “epigenetic clock”, based on DNA methylation levels at specific sites across the genome, which are strongly correlated with chronological age. The deviation of the DNA methylation (DNAm)-predicted age from the chronological age, defined as “age acceleration”, is used as an index of an individual’s rate of aging. Here, we estimated blood DNAm age in African-Americans from the Atherosclerosis Risk in Communities (ARIC) study using two methodologies, and examined the cross-sectional association between WMH on MRI and measures of accelerated epigenetic aging. We hypothesized that DNAm age acceleration, defined as the residual value from the regression of the predicted DNAm age onto chronological age, is associated with greater WMH burden independently of chronological age and other known risk factors, including sex, body mass index, systolic blood pressure, hypertension, diabetes, and current smoking. DNA methylation was measured using the Illumina HM450 array on genomic DNA extracted from blood samples of African-American participants of the ARIC study. We estimated DNAm age using two published algorithms in 713 individuals aged 51-73 with both DNAm and brain MRI data. Linear regression models were used to estimate the association of the natural log-transformed WMH burden with each measure of age acceleration adjusting for covariates. Age acceleration was significantly associated with WMH burden and results were similar for both estimates of DNAm age. Each unit increase in WMH burden (on the log scale) was associated with a 1.2 and 1.3 year increase in DNAm age after accounting for chronological age and other known risk factors (P=0.01 and 0.004). Further adjustment for blood cell composition did not meaningfully change these results. In this population-based study of middle-aged to older African-American adults, we report evidence of an association between accelerated epigenetic aging of blood and increased WMH burden, independent of known risk factors, including chronologic age. Additional studies are ongoing to clarify whether DNAm age is simply a marker of the rate of aging or reflects biological mechanisms implicated in the aging of the cerebral white matter.

Background: Epigenetic modifications such DNA methylation variation comprise a potentially useful new class of biomarkers that may improve coronary heart disease (CHD) risk stratification, or better capture early pathophysiological processes. However, replicated associations of DNA methylation and CHD are few, and existing studies are primarily cross-sectional and restricted to European ancestry populations. Given the strong association of excess adiposity with CHD risk, we tested 41 DNA methylation variants (CpG sites) that were previously reported to be associated with BMI in African Americans (AA), and tested their association with incident CHD in AA adults. Methods: Genome-wide DNA methylation variation was assayed at a single time point in stored frozen leukocyte samples using the Illumina HM450K chip in a subset of 1,797 AA participants in the Atherosclerosis Risk in Communities (ARIC) study, a prospective cohort study of cardiovascular disease risk conducted in four U.S. communities. Methylation beta values and other continuous covariates were winsorized prior to analysis to reduce outlier influence. Incident CHD cases were identified through annual telephone interviews and medical records review. Proportional hazards regression (frailty) models examined the relationship between DNA methylation beta values and incident CHD with separate models for each of the 41 CpGs, with a random effect specified for chip. Fully adjusted models included age, BMI, sex, center, education, household income, leisure time activity, alcohol and tobacco use, white blood cell count and imputed cell type differentials. To explore the relationship between DNA methylation and CHD risk accounting for major CHD risk factors, mediator models additionally contained prevalent hypertension status, blood glucose, and total and HDL cholesterol. A Bonferroni-corrected p value of 0.00122 was set as the threshold for statistical significance. Results: There were 224 cases of incident CHD out of 1,797 individuals at risk. One CpG, cg09664445 near CLUH was significantly associated with incident CHD in the full (HR=1.47, 95%CI=1.26, 1.72) and mediator model (HR=1.46, 95% CI=1.24, 1.71) while cg06500161 near ABCG1 was significant in the full model only (HR=1.34, 95% CI=1.15, 1.56). Conclusion: Two obesity-related DNA methylation variants were associated with incident CHD independent of known risk factors and potential confounders. In the literature, CLUH is involved in mitochondrial biogenesis while promoter hypermethylation of ABCG1 was previously found to increase CHD risk and atherosclerosis. Replication in additional cohorts is required to further investigate the predictive value of DNA methylation variants over established risk factors and biomarkers for CHD.