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Background: Plasma proteins are critical mediators of cardiovascular processes and are the targets of many drugs. Previous efforts to characterize the genetic architecture of the plasma proteome have been limited by a focus on individuals of European descent and leveraged genotyping arrays and imputation. Here we describe whole genome sequence analysis of the plasma proteome in individuals with greater African ancestry, increasing our power to identify novel genetic determinants. Methods: Proteomic profiling of 1301 proteins was performed in 1852 Black adults from the Jackson Heart Study using aptamer-based proteomics (SomaScan). Whole genome sequencing association analysis was ascertained for all variants with minor allele count ≥5. Results were validated using an alternative, antibody-based, proteomic platform (Olink) as well as replicated in the Multi-Ethnic Study of Atherosclerosis and the HERITAGE Family Study (Health, Risk Factors, Exercise Training and Genetics). Results: We identify 569 genetic associations between 479 proteins and 438 unique genetic regions at a Bonferroni-adjusted significance level of 3.8×10 -11 . These associations include 114 novel locus-protein relationships and an additional 217 novel sentinel variant-protein relationships. Novel cardiovascular findings include new protein associations at the APOE gene locus including ZAP70 (sentinel single nucleotide polymorphism [SNP] rs7412-T, β=0.61±0.05, P =3.27×10 -30 ) and MMP-3 (β=-0.60±0.05, P =1.67×10 -32 ), as well as a completely novel pleiotropic locus at the HPX gene, associated with 9 proteins. Further, the associations suggest new mechanisms of genetically mediated cardiovascular disease linked to African ancestry; we identify a novel association between variants linked to APOL1-associated chronic kidney and heart disease and the protein CKAP2 (rs73885319-G, β=0.34±0.04, P =1.34×10 -17 ) as well as an association between ATTR amyloidosis and RBP4 levels in community-dwelling individuals without heart failure. Conclusions: Taken together, these results provide evidence for the functional importance of variants in non-European populations, and suggest new biological mechanisms for ancestry-specific determinants of lipids, coagulation, and myocardial function.

Introduction: Clonal hematopoiesis of indeterminate potential (CHIP) is an aging-related accumulation of somatic mutations in hematopoietic stem cells, leading to clonal expansion. CHIP presence has been implicated in elevated risks for coronary heart disease (CHD) and death, but its association with incident type 2 diabetes (T2D) is unknown. Hypothesis: We hypothesized that CHIP is associated with elevated risk of incident T2D. Methods: CHIP was derived from whole genome sequencing of blood DNA in NHLBI Trans-omics for Precision Medicine (TOPMed) cohorts. We analyzed 17,637 participants without prior T2D, cardiovascular disease, or cancer at blood draw, with prospective follow-up for incident T2D. We evaluated baseline prevalence of CHIP vs. no CHIP with incident T2D risk using Cox regression. We also investigated CHIP variants previously related to CHD: DNMT3A , TET2 , ASXL1 , JAK2 , and TP53 . We estimated multivariable-adjusted hazard ratios and 95% confidence intervals (HR [CI]) adjusted for age, sex, body mass index, smoking, alcohol, and education. We combined cohort estimates via fixed effects meta-analysis. Results: On average, participants were age 63.4 years (SD=11.5) and 76% female. Prevalence of CHIP was 6.0% (1,055) at baseline. There were 2,467 incident T2D cases over mean=9.8 years follow-up. Compared to those without a mutation, having CHIP was associated with a 23% higher T2D risk, both overall (combined HR=1.23; 95% CI=1.04, 1.45), and among those with CHD-related CHIP mutations (87% of total CHIP): HR=1.23 (1.03, 1.46). Although those with CHIP mutations of TET2 (HR=1.48; 1.05, 2.08) and ASXL1 (HR=1.76; 1.03, 2.99) had larger elevations in T2D risk, and DNMT3A was suggestive of increased T2D risk (HR=1.15; 0.93, 1.43), statistical power was limited for JAK2 and TP53 mutation analyses. Conclusions: CHIP was associated with higher incidence of T2D. CHIP mutations located on loci previously implicated in aging and CHD were also related to T2D, suggesting shared pathology of atherosclerosis and T2D.

Background: Premature menopause is an independent risk factor for cardiovascular disease in women, but mechanisms underlying this association remain unclear. Clonal hematopoiesis of indeterminate potential (CHIP), the age-related expansion of hematopoietic cells with leukemogenic mutations without detectable malignancy, is associated with accelerated atherosclerosis. Whether premature menopause is associated with CHIP is unknown. Methods: We included postmenopausal women from the UK Biobank (n=11 495) aged 40 to 70 years with whole exome sequences and from the Women’s Health Initiative (n=8111) aged 50 to 79 years with whole genome sequences. Premature menopause was defined as natural or surgical menopause occurring before age 40 years. Co–primary outcomes were the presence of any CHIP and CHIP with variant allele frequency >0.1. Logistic regression tested the association of premature menopause with CHIP, adjusted for age, race, the first 10 principal components of ancestry, smoking, diabetes, and hormone therapy use. Secondary analyses considered natural versus surgical premature menopause and gene-specific CHIP subtypes. Multivariable-adjusted Cox models tested the association between CHIP and incident coronary artery disease. Results: The sample included 19 606 women, including 418 (2.1%) with natural premature menopause and 887 (4.5%) with surgical premature menopause. Across cohorts, CHIP prevalence in postmenopausal women with versus without a history of premature menopause was 8.8% versus 5.5% ( P P =0.004; CHIP with variant allele frequency >0.1: odds ratio, 1.40 [95% CI, 1.10–1.79]; P =0.007). Associations were larger for natural premature menopause (all CHIP: odds ratio, 1.73 [95% CI, 1.23–2.44]; P =0.001; CHIP with variant allele frequency >0.1: odds ratio, 1.91 [95% CI, 1.30–2.80]; P DNMT3A CHIP was significantly associated with premature menopause. Among postmenopausal middle-aged women, CHIP was independently associated with incident coronary artery disease (hazard ratio associated with all CHIP: 1.36 [95% CI, 1.07–1.73]; P =0.012; hazard ratio associated with CHIP with variant allele frequency >0.1: 1.48 [95% CI, 1.13–1.94]; P =0.005). Conclusions: Premature menopause, especially natural premature menopause, is independently associated with CHIP among postmenopausal women. Natural premature menopause may serve as a risk signal for predilection to develop CHIP and CHIP-associated cardiovascular disease.

Background: Clonal hematopoiesis of indeterminate potential (CHIP) refers to clonal expansion of hematopoietic stem cells attributable to acquired leukemic mutations in genes such as DNMT3A or TET2 . In humans, CHIP associates with prevalent myocardial infarction. In mice, CHIP accelerates atherosclerosis and increases IL-6/IL-1β expression, raising the hypothesis that IL-6 pathway antagonism in CHIP carriers would decrease cardiovascular disease (CVD) risk. Methods: We analyzed exome sequences from 35 416 individuals in the UK Biobank without prevalent CVD, to identify participants with DNMT3A or TET2 CHIP. We used the IL6R p.Asp358Ala coding mutation as a genetic proxy for IL-6 inhibition. We tested the association of CHIP status with incident CVD events (myocardial infarction, coronary revascularization, stroke, or death), and whether it was modified by IL6R p.Asp358Ala. Results: We identified 1079 (3.0%) individuals with CHIP, including 432 (1.2%) with large clones (allele fraction >10%). During 6.9-year median follow-up, CHIP associated with increased incident CVD event risk (hazard ratio, 1.27 [95% CI, 1.04–1.56], P =0.019), with greater risk from large CHIP clones (hazard ratio, 1.59 [95% CI, 1.21–2.09], P IL6R p.Asp358Ala attenuated CVD event risk among participants with large CHIP clones (hazard ratio, 0.46 [95% CI, 0.29–0.73], P P =0.08; P interaction =0.003). In 9951 independent participants, the association of CHIP status with myocardial infarction similarly varied by IL6R p.Asp358Ala ( P interaction =0.036). Conclusions: CHIP is associated with increased risk of incident CVD. Among carriers of large CHIP clones, genetically reduced IL-6 signaling abrogated this risk.

Introduction: Clonal hematopoiesis of indeterminate potential (CHIP) is a newly recognized aging-related condition due to clonal expansion of mutated hematopoietic stem cells (HSC) that results in increased risk for coronary artery disease (CAD). The extent to which CHIP is associated with stroke risk is not well understood. Methods: CHIP genotypes were obtained from 6 cohort studies [the Atherosclerosis Risk in Communities Study (ARIC), the Cardiovascular Health Study (CHS), the Framingham Heart Study (FHS), the Jackson Heart Study (JHS), the Multi-Ethnic Study of Atherosclerosis (MESA), the Women’s Health Initiative (WHI)] and two electronic health record-based biobanks [UK Biobank (UKBB) and Massachusetts General Brigham Biobank (MGBB)]. Incident stroke was ascertained by physician adjudicators in the cohort studies, and by ICD codes in the biobanks. Cox proportional hazards models were fitted with adjustment for age, sex, diabetes mellitus, smoking status (never, past, current) and race. Fixed-effects meta-analysis was used to estimate pooled effect sizes. Results: A total of 74,306 participants from 8 studies were included. In the fixed-effects meta-analysis, CHIP mutations were associated with an increased risk of total stroke (HR= 1.17, 95% CI 1.05-1.28) ( Figure 1 ). In analysis of stroke subgroups, the risk was greater for hemorrhagic (HR= 1.37, 95% CI 1.15-1.59) than ischemic stroke (HR= 1.13, 95% CI 1.00-1.26). Individuals with particularly expanded CHIP mutations (i.e. variant allele fraction >10%), showed similar effect estimates of association for total stroke, ischemic stroke, or hemorrhagic stroke were observed (HR any stroke = 1.21, 95% CI 1.09-1.34; HR ischemic stroke = 1.15, 95% CI 1.01-1.30; HR hemorrhagic stroke = 1.43, 95% CI 1.20-1.67) . Conclusions: CHIP is associated with incident ischemic and hemorrhagic stroke.

Background: Approximately 13% of black individuals carry 2 copies of the apolipoprotein L1 ( APOL1 ) risk alleles G1 or G2, which are associated with 1.5- to 2.5-fold increased risk of chronic kidney disease. There have been conflicting reports as to whether an association exists between APOL1 risk alleles and cardiovascular disease (CVD) that is independent of the effects of APOL1 on kidney disease. We sought to test the association of APOL1 G1/G2 alleles with coronary artery disease, peripheral artery disease, and stroke among black individuals in the Million Veteran Program. Methods: We performed a time-to-event analysis of retrospective electronic health record data using Cox proportional hazard and competing-risks Fine and Gray subdistribution hazard models. The primary exposure was APOL1 risk allele status. The primary outcome was incident coronary artery disease among individuals without chronic kidney disease during the 12.5-year follow-up period. We separately analyzed the cross-sectional association of APOL1 risk allele status with lipid traits and 115 cardiovascular diseases using phenome-wide association. Results: Among 30 903 black Million Veteran Program participants, 3941 (13%) carried the 2 APOL1 risk allele high-risk genotype. Individuals with normal kidney function at baseline with 2 risk alleles had slightly higher risk of developing coronary artery disease compared with those with no risk alleles (hazard ratio, 1.11 [95% CI, 1.01–1.21]; P =0.039). Similarly, modest associations were identified with incident stroke (hazard ratio, 1.20 [95% CI, 1.05–1.36; P =0.007) and peripheral artery disease (hazard ratio, 1.15 [95% CI, 1.01–1.29l; P =0.031). When both cardiovascular and renal outcomes were modeled, APOL1 was strongly associated with incident renal disease, whereas no significant association with the CVD end points could be detected. Cardiovascular phenome-wide association analyses did not identify additional significant associations with CVD subsets. Conclusions: APOL1 risk variants display a modest association with CVD, and this association is likely mediated by the known APOL1 association with chronic kidney disease.

Introduction: Premature menopause is an independent risk factor for cardiovascular disease in women, but mechanisms underlying this association remain unclear. Clonal hematopoiesis of indeterminate potential (CHIP), the age-related expansion of hematopoietic cells with leukemogenic mutations, is associated with accelerated atherosclerosis. Whether premature menopause is associated with CHIP is unknown. Methods: We included postmenopausal women from the UK Biobank (N=11,509) aged 40-70 years with whole exome sequences and from the Women’s Health Initiative (WHI, N=8,111) aged 50-79 years with whole genome sequences. Premature menopause was defined as natural or surgical menopause occurring before age 40 years. Co-primary outcomes were the presence of (1) any CHIP and (2) CHIP with variant allele fraction (VAF) >0.1. Logistic regression tested the association of premature menopause with CHIP, adjusted for age, race, the first 10 principal components, smoking, diabetes mellitus, and hormone therapy use. Results: Across cohorts, prevalence of CHIP in women with vs. without a history of premature menopause was 8.8% vs. 5.5% (P0.1: 1.91, 95% CI 1.30-2.80; Figure ). In gene-specific analyses, DNMT3A CHIP had a strong association with natural premature menopause but no association with surgical premature menopause. Among postmenopausal middle-aged women in the UK Biobank and WHI, CHIP was independently associated with incident coronary artery disease (meta-analyzed HR 1.52, 95% CI 1.17-1.99). Conclusions: Premature menopause, especially natural premature menopause, is independently associated with CHIP. CHIP may contribute to the excess cardiovascular risk associated with premature menopause.

Introduction: Clonal hematopoiesis of indeterminate potential (CHIP) is an age-related disorder associated with increased risk of atherosclerotic cardiovascular disease (ASCVD). Mechanistic studies of CHIP implicate inflammatory pathways underlying this relationship. Although inflammation is a well-established component of chronic kidney disease (CKD), linked to both CKD progression and ASCVD in CKD patients, CHIP has not been investigated in a CKD setting. Objective: To estimate the prevalence of CHIP in patients with CKD and to examine the cross-sectional associations between CHIP and biomarkers that were previously related to CKD progression and ASCVD among CKD patients. Methods: The current study was conducted among 598 Chronic Renal Insufficiency Cohort (CRIC) study participants with whole-exome sequencing data and baseline measures of fibrinogen, interleukin (IL)-6, serum albumin, and tumor necrosis factor-α. CHIP was detected from sequencing data using MuTect2. CHIP was defined as the presence of a somatic hematologic malignancy-associated mutation with a variant allele frequency (VAF) of at least 2%. CHIP was also categorized ordinally by clone size as no CHIP, small CHIP clone (VAF Results: CHIP was detected in a total of 28 individuals from the WES study (4.7%). Among those 70 years of age and older, we detected a CHIP prevalence of nearly 16%. As expected, participants with CHIP were older than those without CHIP (mean age: 67 and 58 years, respectively; P. Age-adjusted models showed strong associations between CHIP and both fibrinogen and IL-6 with odds ratios of 2.49 (95% CI: 1.09, 5.71) and 2.45 (95% CI: 1.05, 5.72), respectively. After multivariable adjustment, only fibrinogen remained associated with CHIP with an odds ratio of 4.70 (95% CI: 1.69, 13.0). Consistent with these findings, there was a strong dose-dependent association between CHIP clone size and fibrinogen in multivariable adjusted analyses (P for linear trend=0.009). Compared to those without CHIP, odds ratios for higher fibrinogen tertile were 3.0 (95% CI: 0.84, 11.3) and 4.7 (95% CI: 1.29, 16.7) among those with small and large CHIP clone sizes, respectively. Conclusions: CHIP prevalence was higher among CKD patients in the current study compared to previous estimates from the general population. Furthermore, a strong, dose-dependent association between CHIP and fibrinogen was identified.

Background: Clonal hematopoiesis of indeterminate potential (CHIP) occurs when there is expansion of leukocyte clones in the blood due to mutations in hematopoietic stem cells. CHIP is associated with a high risk of hematologic malignancy and increased risk of cardiovascular disease (CVD). Although the environmental risk factors for CHIP remain poorly understood, radon is a ubiquitous mutagen and may deliver non-negligible doses of α-radiation to bone marrow that trigger CHIP development. Methods: We conducted a cross-sectional study of 10,495 postmenopausal women without hematologic malignancy from the Women’s Health Initiative clinical trials and observational study (mean age: 69 years; 82% white; 9% African American; 4% Hispanic/Latina; 3% Asian). Using blood from the 1993-1998 screening visit or a subsequent annual visit, and whole genome sequence data from the Trans-Omics for Precision Medicine project, we identified CHIP using the GATK Mu TECT2 somatic variant caller, a pre-specified list of leukemogenic driver mutations in 74 genes, and a threshold variant allele fraction > 0.02. We linked geocoded participant addresses at the time of blood draw to county-level, indoor, screening radon concentrations that were predicted by the Environmental Protection Agency (EPA) in 1993 using data on indoor radon, geology, aerial radioactivity, soil parameters, and foundation types. Radon exposure was classified as follows: Zone 3 (< 2 pCi/L), Zone 2 (2-4 pCi/L), and Zone 1 (> 4 pCi/L), the level at which EPA recommends remediation. We estimated the radon-related risk of CHIP as an odds ratio (OR, 95% CI) using logistic regression with and without adjustment for study design, participant sampling, age, race/ethnicity, smoking, and other sociodemographic / behavioral covariates. Results: We identified CHIP in 887 (8.5% of) participants. 3106 (29.6%), 3982 (37.9%), and 3407 (32.5%) had Zone 3, 2, and 1 radon exposures. The corresponding percentage of participants with CHIP across zones was 7.6%, 8.6%, and 9.1%. Relative to participants in Zone 3, those in Zones 2 and 1 had a higher adjusted risk of CHIP: OR (95% CI) = 1.13 (0.95, 1.35) and 1.24 (1.03, 1.48). Conclusion: Risk of CHIP was positively associated with indoor radon concentrations in this cross-sectional study of post-menopausal women. Longitudinal study of temporally integrated, in-home radon exposures, incident CHIP, and CVD would help confirm this novel radon-CHIP association and place it in context.

Background: Although the etiology of clonal hematopoiesis of indeterminate potential (CHIP) remains unclear, CHIP-defining somatic mutations within hematopoietic stem cells appear to expand peripheral blood leukocyte populations, promote inflammation, and thereby increase cardiovascular disease (CVD) risk. Moreover, high noise exposures have been linked to chromosomal aberrations in bone marrow and DNA repair in peripheral blood leukocytes. We therefore examined the potential of aircraft noise exposure as a novel risk factor for CHIP. Methods: We leveraged cross-sectional data on 10,050 postmenopausal women without prior hematologic malignancy in a Women’s Health Initiative (WHI) ancillary study of 5,309 women with stroke and/or venous thromboembolic disease and 4,741 controls. We ascertained CHIP using Trans-Omics for Precision Medicine (TOPMed) whole-genome sequencing data, the GATK Mu TECT2 somatic variant caller, a pre-specified list of leukemogenic driver mutations in 74 genes, and a threshold variant allele frequency of > 0.02. In cooperation with the Federal Aviation Administration, we generated day-night-level (DNL) noise contours around 90 major U.S. airports using the Aviation Environmental Design Tool noise modelling software. The DNL imposes a penalty for nighttime noise exposure and is the primary means for assessing and regulating noise exposure in the U.S. We estimated geocoded participant address-specific, annual average DNL aircraft noise exposures in decibels (dB) from the contours on the day of blood draw and categorized individuals as exposed or non-exposed (DNL ≥ or < 45dB). We estimated the noise-related risk of CHIP as an odds ratio, 95% confidence interval (OR, 95% CI) using logistic regression before and after adjustment for age, race / ethnicity, case-control status, smoking, alcohol use, body mass index, physical activity, hearing loss, education, and neighborhood socioeconomic status. Results: Among this population of postmenopausal women (Mean age: 68.7 years; White: 82.1%; African American: 12.3%), 19.4% were exposed to aircraft noise, and 8.4% had CHIP. The age-adjusted CHIP proportion was higher among whites (8.1%) than African Americans (7.3%) and other racial/ethnic groups (6.4%). CHIP was also more common among women aged ≥ 70 years (11.5%) than those aged 60-69 years (7.5%) or 50-59 years (3.8%). Compared to non-exposed women, those exposed to aircraft noise were not at increased risk of CHIP: OR unadjusted (95% CI) = 0.95 (0.80, 1.14) and OR adjusted (95% CI) = 0.97 (0.81, 1.16). Results were insensitive to dichotomization of noise exposure at 55 dB and further exclusion of women with hearing loss. Conclusion: Our study found no evidence of an association between aircraft noise and CHIP suggesting that aircraft noise may not be a factor contributing to CHIP-defining somatic mutations linked to CVD.