👤 Michael J McCarthy

To delineate organ-specific and systemic drivers of metabolic dysfunction-associated steatotic liver disease (MASLD), we applied integrative causal inference across clinical, imaging, and proteomic domains in individuals with and without type 2 diabetes (T2D). Bayesian network analyses and complementary two-sample Mendelian randomization were used to quantify causal pathways linking adipose distribution, glycemia, and insulin dynamics with liver fat in the IMI-DIRECT prospective cohort study. Data included frequently sampled metabolic challenge tests, MRI-derived abdominal and hepatic fat content, serological biomarkers, and Olink plasma proteomics from 331 adults with new-onset T2D and 964 adults without diabetes, with harmonized protocols enabling replication. High basal insulin secretion rate (BasalISR), estimated via C-peptide deconvolution, emerged as the primary potential causal driver of liver fat accumulation in both cohorts. BasalISR, a clearance-independent measure of β-cell insulin output distinct from peripheral insulin levels, was independently linked to hepatic steatosis. Visceral adipose tissue exhibited bidirectional associations with liver fat, suggesting a self-reinforcing metabolic loop. Of 446 analyzed proteins, 34 mapped to these metabolic networks (27 in the non-diabetes network, 18 in the T2D network, and 11 shared). Key proteins directly associated with liver fat included GUSB, ALDH1A1, LPL, IGFBP1/2, CTSD, HMOX1, FGF21, AGRP, and ACE2. Sex-stratified analyses identified GUSB in females and LEP in males as the strongest protein predictors of liver fat. BasalISR may better capture early β-cell-driven disturbances contributing to MASLD. These findings outline a multifactorial, sex- and disease stage-specific proteo-metabolic architecture of hepatic steatosis and identify potential biomarkers or therapeutic targets. Show less

Obicetrapib is a potent, selective cholesteryl ester transfer protein (CETP) inhibitor that significantly lowers low-density lipoprotein cholesterol (LDL-C). Additive reductions in LDL-C occur when obicetrapib is combined with ezetimibe. The impact of obicetrapib and ezetimibe fixed-dose combination (FDC) on coronary plaque burden is unknown. Favorable changes in noncalcified coronary atherosclerotic plaque volume (NCPV) may indicate a potential beneficial effect on atherosclerotic cardiovascular disease (ASCVD) events. REMBRANDT is a placebo-controlled, double-blind, randomized trial designed to assess the efficacy of obicetrapib and ezetimibe FDC on coronary plaque burden. Individuals aged 45 years or older with ASCVD (imaging evidence of vascular disease or clinically manifested ASCVD) and an LDL-C of ≥70 mg/dL despite maximally tolerated lipid-modifying therapy are eligible to participate. Eligible participants (N = 300) will be randomized in a 1:1 ratio to obicetrapib 10 mg and ezetimibe 10 mg FDC once daily or placebo tablet once daily. The primary efficacy outcome of REMBRANDT is percent change in total NCPV from baseline to 18 months as assessed by coronary computed tomographic angiography (CCTA). Secondary endpoints include absolute change in total NCPV, percent and absolute change in NCPV in the most diseased coronary segment, percent change in LDL-C, and change in perivascular fat attenuation index from baseline to 18 months. The REMBRANDT trial will determine whether the favorable effects of obicetrapib and ezetimibe FDC on LDL-C translate to a reduction in coronary plaque burden as a potential mechanism for ASCVD risk reduction. NCT06305559. Show less

Hundreds of genetic associations for asthma have been identified, yet translating these findings into mechanistic insights remains challenging. We leveraged plasma proteomics from the UK Biobank Pharma Proteomics Project (UKB-PPP) to identify biomarkers and effectors of asthma risk or heterogeneity using genetic causal inference approaches. We identified 609 proteins associated with asthma status (269 proteins after controlling for body mass index [BMI] and smoking). Analysis of genetically predicted protein levels identified 70 proteins with putative causal roles in asthma risk, including known drug targets and proteins without prior genetic evidence in asthma (e.g., GCHFR, TDRKH, and CLEC7A). The genetic architecture of causally associated proteins provided evidence for a Toll-like receptor (TLR)1-interleukin (IL)-27 asthma axis. Lastly, we identified evidence of causal relationships between proteins and heterogeneous aspects of asthma biology, including between TSPAN8 and neutrophil counts. These findings illustrate that integrating biobank-scale genetics and plasma proteomics can provide a framework to identify therapeutic targets and mechanisms underlying disease risk and heterogeneity. Show less

To delineate organ-specific and systemic drivers of metabolic dysfunction-associated steatotic liver disease (MASLD), we applied integrative causal inference across clinical, imaging, and proteomic domains in individuals with and without type 2 diabetes (T2D). We used Bayesian network analyses to quantify causal pathways linking adipose distribution, glycemia, and insulin dynamics with fatty liver using data from the IMI-DIRECT prospective cohort study. Measurements were made of glucose and insulin dynamics (using frequently-sampled metabolic challenge tests), MRI-derived abdominal and liver fat content, serological biomarkers, and Olink plasma proteomics from 331 adults with new-onset T2D and 964 adults free from diabetes at enrolment. The common protocols used in these two cohorts provided the opportunity for replication analyses to be performed. When the direction of the effect could not be determined with high probability through Bayesian networks, complementary two-sample Mendelian randomization (MR) was employed. High basal insulin secretion rate (BasalISR) was identified as the primary causal driver of liver fat accumulation in both diabetes and non-diabetes. Excess visceral adipose tissue (VAT) was bidirectionally associated with liver fat, indicating a self-reinforcing metabolic loop. Basal insulin clearance (Clinsb) worsened as a consequence of liver fat accumulation to a greater degree before the onset of T2D. Out of 446 analysed proteins, 34 mapped to these metabolic networks and 27 were identified in the non-diabetes network, 18 in the diabetes network, and 11 were common between the two networks. Key proteins directly associated with liver fat included GUSB, ALDH1A1, LPL, IGFBP1/2, CTSD, HMOX1, FGF21, AGRP, and ACE2. Sex-stratified analyses revealed distinct proteomic drivers: GUSB and LEP were most predictive of liver fat in females and males, respectively. Basal insulin hypersecretion is a modifiable, causal driver of MASLD, particularly prior to glycaemic decompensation. Our findings highlight a multifactorial, sex- and disease-stage-specific proteo-metabolic architecture of hepatic steatosis. Proteins such as GUSB, ALDH1A1, LPL, and IGFBPs warrant further investigation as potential biomarkers or therapeutic targets for MASLD prevention and treatment. Show less

The accumulation and aggregation of beta-amyloid (Aβ) peptides contributes to neuronal dysfunction and death. These Aβ peptides originate from a transmembrane protein known as amyloid precursor protein (APP), which can be processed via two competing pathways. Alpha-secretase (ADAM10) cleavage is thought to be neuroprotective while beta-secretase (BACE1) cleavage results in the production of Aβ. Aerobic exercise reduces BACE1 activity, but the mechanisms involved are unknown though several exercise-induced mediators such as lactate may be involved. The current study examined whether systemic lactate can alter APP processing and BACE1 and ADAM10 activity. Mice were randomly assigned to one of four groups (n = 10 per group): (1) sedentary; (2) lactate-injection (1.0 g kg Show less

We investigated naporafenib (LXH254), a pan-RAF kinase inhibitor, with or without spartalizumab, in patients with advanced solid tumors harboring MAPK pathway alterations. This first-in-human phase 1 study had two dose-escalation arms: single-agent naporafenib (starting at 100 mg once-daily [QD]) and naporafenib (starting at the recommended dose/regimen)/spartalizumab (400 mg every 4 weeks). The naporafenib/spartalizumab dose-expansion part enrolled patients with KRAS-mutated non-small cell lung cancer (NSCLC) and NRAS-mutated melanoma. The primary objectives were to establish the maximum tolerated doses (MTD)/recommended doses for expansion (RDE) and evaluate tolerability and safety. A total of 142 patients were included in the naporafenib dose-escalation (n = 87), naporafenib/spartalizumab dose-escalation (n = 12) and naporafenib/spartalizumab dose-expansion (n = 43) arms. The MTD/RDE of naporafenib was 600 mg twice-daily (BID). In naporafenib escalation, five patients experienced 7 dose-limiting toxicities: decreased platelet count (1200 mg QD); neuralgia, maculopapular rash, pruritus (600 mg BID); increased blood bilirubin, hyponatremia, peripheral sensory neuropathy (800 mg BID). No DLTs occurred in the naporafenib/spartalizumab arm: the RDE was established at 400 mg BID. The most common treatment-related adverse events were rash and dermatitis acneiform (each 24.1%; naporafenib), nausea and pruritus (each 33.3%; naporafenib/spartalizumab; escalation) and rash (39.5%; naporafenib/spartalizumab; expansion). Naporafenib reduced DUSP6 expression in tumors. Two partial responses (PRs) occurred in naporafenib escalation, and 1 complete response and 3 PRs in the naporafenib/spartalizumab NRAS-mutated melanoma and KRAS-mutated NSCLC arms, respectively. Naporafenib, with or without spartalizumab, showed an acceptable safety profile, pharmacodynamic activity and limited antitumor activity. Additional naporafenib combination therapies are currently under investigation. Show less

Loss-of-function mutations in melanocortin-4 receptor (MC4R) are the most common cause of monogenic obesity, a severe type of early-onset obesity. Our aim was to determine the prevalence of MC4R mutations in a cohort of 97 Argentinian children with early-onset obesity. We found two novel mutations (p.V52E and p.G233S) and estimated a prevalence of 2.1%. We investigated the pathogenicity of mutations in HEK293T cells expressing wild-type or mutant MC4R and found that both mutants exhibited reduced plasma membrane expression and altered agonist-induced cAMP responses, with no changes in basal activity. Besides, MC4R G233S mutant demonstrated an altered agonist-dependent inhibition of voltage-gated calcium channels type 2.2. Results using a Gα Show less

Identifying genetic determinants of reproductive success may highlight mechanisms underlying fertility and identify alleles under present-day selection. Using data in 785,604 individuals of European ancestry, we identified 43 genomic loci associated with either number of children ever born (NEB) or childlessness. These loci span diverse aspects of reproductive biology, including puberty timing, age at first birth, sex hormone regulation, endometriosis and age at menopause. Missense variants in ARHGAP27 were associated with higher NEB but shorter reproductive lifespan, suggesting a trade-off at this locus between reproductive ageing and intensity. Other genes implicated by coding variants include PIK3IP1, ZFP82 and LRP4, and our results suggest a new role for the melanocortin 1 receptor (MC1R) in reproductive biology. As NEB is one component of evolutionary fitness, our identified associations indicate loci under present-day natural selection. Integration with data from historical selection scans highlighted an allele in the FADS1/2 gene locus that has been under selection for thousands of years and remains so today. Collectively, our findings demonstrate that a broad range of biological mechanisms contribute to reproductive success. Show less

The endothelial glycocalyx regulates vascular permeability, inflammation, and coagulation, and acts as a mechanosensor. The loss of glycocalyx can cause endothelial injury and contribute to several microvascular complications and, therefore, may promote diabetic retinopathy. Studies have shown a partial loss of retinal glycocalyx in diabetes, but with few molecular details of the changes in glycosaminoglycan (GAG) composition. Therefore, the purpose of our study was to investigate the effect of hyperglycemia on GAGs of the retinal endothelial glycocalyx. GAGs were isolated from rat retinal microvascular endothelial cells (RRMECs), media, and retinas, followed by liquid chromatography-mass spectrometry assays. Quantitative real-time polymerase chain reaction was used to study mRNA transcripts of the enzymes involved in GAG biosynthesis. Hyperglycemia significantly increased the shedding of heparan sulfate (HS), chondroitin sulfate (CS), and hyaluronic acid (HA). There were no changes to the levels of HS in RRMEC monolayers grown in high-glucose media, but the levels of CS and HA decreased dramatically. Similarly, while HA decreased in the retinas of diabetic rats, the total GAG and CS levels increased. Hyperglycemia in RRMECs caused a significant increase in the mRNA levels of the enzymes involved in GAG biosynthesis (including EXTL-1,2,3, EXT-1,2, ChSY-1,3, and HAS-2,3), with these increases potentially being compensatory responses to overall glycocalyx loss. Both RRMECs and retinas of diabetic rats exhibited glucose-induced alterations in the disaccharide compositions and sulfation of HS and CS, with the changes in sulfation including N,6-O-sulfation on HS and 4-O-sulfation on CS. Show less

Pancreatic beta-cell glucose sensitivity is the slope of the plasma glucose-insulin secretion relationship and is a key predictor of deteriorating glucose tolerance and development of type 2 diabetes. However, there are no large-scale studies looking at the genetic determinants of beta-cell glucose sensitivity. To understand the genetic determinants of pancreatic beta-cell glucose sensitivity using genome-wide meta-analysis and candidate gene studies. We performed a genome-wide meta-analysis for beta-cell glucose sensitivity in subjects with type 2 diabetes and nondiabetic subjects from 6 independent cohorts (n = 5706). Beta-cell glucose sensitivity was calculated from mixed meal and oral glucose tolerance tests, and its associations between known glycemia-related single nucleotide polymorphisms (SNPs) and genome-wide association study (GWAS) SNPs were estimated using linear regression models. Beta-cell glucose sensitivity was moderately heritable (h2 ranged from 34% to 55%) using SNP and family-based analyses. GWAS meta-analysis identified multiple correlated SNPs in the CDKAL1 gene and GIPR-QPCTL gene loci that reached genome-wide significance, with SNP rs2238691 in GIPR-QPCTL (P value = 2.64 × 10-9) and rs9368219 in the CDKAL1 (P value = 3.15 × 10-9) showing the strongest association with beta-cell glucose sensitivity. These loci surpassed genome-wide significance when the GWAS meta-analysis was repeated after exclusion of the diabetic subjects. After correction for multiple testing, glycemia-associated SNPs in or near the HHEX and IGF2B2 loci were also associated with beta-cell glucose sensitivity. We show that, variation at the GIPR-QPCTL and CDKAL1 loci are key determinants of pancreatic beta-cell glucose sensitivity. Show less

The melanocortin 4 receptor (MC4R) is a G protein-coupled receptor that plays major roles in the central control of energy balance. Loss-of-function mutations of MC4R constitute the most common monogenic cause of early-onset extreme obesity in humans, whereas gain-of-function mutations appear to be protective. In particular, two relatively frequent alleles carrying the non-synonymous coding mutations V103I or I251L are associated with lower risks of obesity and type-2 diabetes. Although V103I and I251L MC4Rs showed more efficient signalling in transfected cells, their specific effects in live animals remain unexplored. Here, we investigated whether the introduction of V103I and I251L mutations into the mouse MC4R leads to a lean phenotype and provides protection against an obesogenic diet. Using CRISPR/Cas9, we generated two novel strains of mice carrying single-nucleotide mutations into the mouse Mc4r which are identical to those present in V103I and I251L MCR4 human alleles, and studied their phenotypic outcomes in mice fed with normal chow or a high-fat diet. In particular, we measured body weight progression, food intake and adiposity. In addition, we analysed glucose homeostasis through glucose and insulin tolerance tests. We found that homozygous V103I females displayed shorter longitudinal length and decreased abdominal white fat, whereas homozygous I251L females were also shorter and leaner due to decreased weight in all white fat pads examined. Homozygous Mc4r Our results demonstrate that mice carrying V103I and I251L MC4R mutations displayed gain-of-function phenotypes that were more evident in females. However, hypermorphic MC4R mutants were as susceptible as their control littermates to the obesogenic and diabetogenic effects elicited by a long-term hypercaloric diet, highlighting the importance of healthy feeding habits even under favourable genetic conditions. Show less

Extracellular vesicles (EVs) mediate critical intercellular communication within healthy tissues, but are also exploited by tumour cells to promote angiogenesis, metastasis, and host immunosuppression under hypoxic stress. We hypothesize that hypoxic tumours synthesize hypoxia-sensitive proteins for packing into EVs to modulate their microenvironment for cancer progression. In the current report, we employed a heavy isotope pulse/trace quantitative proteomic approach to study hypoxia sensitive proteins in tumour-derived EVs protein. The results revealed that hypoxia stimulated cells to synthesize EVs proteins involved in enhancing tumour cell proliferation (NRSN2, WISP2, SPRX1, LCK), metastasis (GOLM1, STC1, MGAT5B), stemness (STC1, TMEM59), angiogenesis (ANGPTL4), and suppressing host immunity (CD70). In addition, functional clustering analyses revealed that tumour hypoxia was strongly associated with rapid synthesis and EV loading of lysosome-related hydrolases and membrane-trafficking proteins to enhance EVs secretion. Moreover, lung cancer-derived EVs were also enriched in signalling molecules capable of inducing epithelial-mesenchymal transition in recipient cancer cells to promote their migration and invasion. Together, these data indicate that lung-cancer-derived EVs can act as paracrine/autocrine mediators of tumorigenesis and metastasis in hypoxic microenvironments. Tumour EVs may, therefore, offer novel opportunities for useful biomarkers discovery and therapeutic targeting of different cancer types and at different stages according to microenvironmental conditions. Show less

CVD is the leading cause of death worldwide, and genetic investigations into the human lipidome may provide insight into CVD risk. The aim of this study was to estimate the heritability of circulating lipid species and their genetic correlation with CVD traits. Targeted lipidomic profiling was performed on 4,492 participants from the Busselton Family Heart Study to quantify the major fatty acids of 596 lipid species from 33 classes. We estimated narrow-sense heritabilities of lipid species/classes and their genetic correlations with eight CVD traits: BMI, HDL-C, LDL-C, triglycerides, total cholesterol, waist-hip ratio, systolic blood pressure, and diastolic blood pressure. We report heritabilities and genetic correlations of new lipid species/subclasses, including acylcarnitine (AC), ubiquinone, sulfatide, and oxidized cholesteryl esters. Over 99% of lipid species were significantly heritable (h Show less

Scabies is a neglected tropical disease of global significance. Our understanding of host-parasite interactions has been limited, particularly in crusted scabies (CS), a severe clinical manifestation involving hyper-infestation of Sarcoptes scabiei mites. Susceptibility to CS may be associated with immunosuppressive conditions but CS has also been seen in cases with no identifiable risk factor or immune deficit. Due to ethical and logistical difficulties with undertaking research on clinical patients with CS, we adopted a porcine model which parallels human clinical manifestations. Transcriptomic analysis using microarrays was used to explore scabies pathogenesis, and to identify early events differentiating pigs with ordinary (OS) and crusted scabies. Pigs with OS (n = 4), CS (n = 4) and non-infested controls (n = 4) were compared at pre-infestation, weeks 1, 2, 4 and 8 post-infestation. In CS relative to OS, there were numerous differentially expressed genes including pro-inflammatory cytokines (IL17A, IL8, IL19, IL20 and OSM) and chemokines involved in immune cell activation and recruitment (CCL20, CCL27 and CXCL6). The influence of genes associated with immune regulation (CD274/PD-L1 and IL27), immune signalling (TLR2, TLR8) and antigen presentation (RFX5, HLA-5 and HLA-DOB) were highlighted in the early host response to CS. We observed similarities with gene expression profiles associated with psoriasis and atopic dermatitis and confirmed previous observations of Th2/17 pronounced responses in CS. This is the first comprehensive study describing transcriptional changes associated with the development of CS and significantly, the distinction between OS and CS. This provides a basis for clinical follow-up studies, potentially identifying new control strategies for this severely debilitating disease. Show less

Semaphorins, specifically type IV, are important regulators of axonal guidance and have been increasingly implicated in poor prognoses in a number of different solid cancers. In conjunction with their cognate PLXNB family receptors, type IV members have been increasingly shown to mediate oncogenic functions necessary for tumor development and malignant spread. In this study, we investigated the role of semaphorin 4C (SEMA4C) in osteosarcoma growth, progression, and metastasis. We investigated the expression and localization of SEMA4C in primary osteosarcoma patient tissues and its tumorigenic functions in these malignancies. We demonstrate that overexpression of SEMA4C promotes properties of cellular transformation, while RNAi knockdown of SEMA4C promotes adhesion and reduces cellular proliferation, colony formation, migration, wound healing, tumor growth, and lung metastasis. These phenotypic changes were accompanied by reductions in activated AKT signaling, G1 cell cycle delay, and decreases in expression of mesenchymal marker genes SNAI1, SNAI2, and TWIST1. Lastly, monoclonal antibody blockade of SEMA4C in vitro mirrored that of the genetic studies. Together, our results indicate a multi-dimensional oncogenic role for SEMA4C in metastatic osteosarcoma and more importantly that SEMA4C has actionable clinical potential. Show less

Insufficient autophagy has been proposed as a mechanism of cellular aging, as this leads to the accumulation of dysfunctional macromolecules and organelles. Premature vascular aging occurs in hypertension. In fact, many factors that contribute to the deterioration of vascular function as we age are accelerated in clinical and experimental hypertension. Previously, we have reported decreased autophagy in arteries from spontaneously hypertensive rats (SHRs); however, the effects of restoring autophagic activity on blood pressure and vascular function are currently unknown. We hypothesized that reconstitution of arterial autophagy in SHRs would decrease blood pressure and improve endothelium-dependent relaxation. We treated 14- to 18-wk-old Wistar rats ( Show less

Although hundreds of genome-wide association studies-implicated loci have been reported for adult obesity-related traits, less is known about the genetics specific for early-onset obesity and with only a few studies conducted in non-European populations to date. Searching for additional genetic variants associated with childhood obesity, we performed a trans-ancestral meta-analysis of 30 studies consisting of up to 13 005 cases (≥95th percentile of body mass index (BMI) achieved 2-18 years old) and 15 599 controls (consistently <50th percentile of BMI) of European, African, North/South American and East Asian ancestry. Suggestive loci were taken forward for replication in a sample of 1888 cases and 4689 controls from seven cohorts of European and North/South American ancestry. In addition to observing 18 previously implicated BMI or obesity loci, for both early and late onset, we uncovered one completely novel locus in this trans-ancestral analysis (nearest gene, METTL15). The variant was nominally associated with only the European subgroup analysis but had a consistent direction of effect in other ethnicities. We then utilized trans-ancestral Bayesian analysis to narrow down the location of the probable causal variant at each genome-wide significant signal. Of all the fine-mapped loci, we were able to narrow down the causative variant at four known loci to fewer than 10 single nucleotide polymorphisms (SNPs) (FAIM2, GNPDA2, MC4R and SEC16B loci). In conclusion, an ethnically diverse setting has enabled us to both identify an additional pediatric obesity locus and further fine-map existing loci. Show less

Pancreatic cancer is a leading cause of mortality worldwide due to the difficulty of detecting early-stage disease and our poor understanding of the mediators that drive progression of hypoxic solid tumors. We therefore used a heavy isotope 'pulse/trace' proteomic approach to determine how hypoxia (Hx) alters pancreatic tumor expression of proteins that confer treatment resistance, promote metastasis, and suppress host immunity. Using this method, we identified that hypoxia stress stimulates pancreatic cancer cells to rapidly translate proteins that enhance metastasis (NOTCH2, NCS1, CD151, NUSAP1), treatment resistance (ABCB6), immune suppression (NFIL3, WDR4), angiogenesis (ANGPT4, ERO1α, FOS), alter cell metabolic activity (HK2, ENO2), and mediate growth-promoting cytokine responses (CLK3, ANGPTL4). Database mining confirmed that elevated gene expression of these hypoxia-induced mediators is significantly associated with poor patient survival in various stages of pancreatic cancer. Among these proteins, the oxidoreductase enzyme ERO1α was highly sensitive to induction by hypoxia stress across a range of different pancreatic cancer cell lines and was associated with particularly poor prognosis in human patients. Consistent with these data, genetic deletion of ERO1α substantially reduced growth rates and colony formation by pancreatic cancer cells when assessed in a series of functional assays Show less

Concentrations of circulating apolipoproteins are strongly linked to risk for coronary artery disease (CAD). The relative importance of the additional knowledge of apolipoprotein concentrations within specific lipoprotein species for CAD risk prediction is limited. This study sought to evaluate the performance of a high-density lipoprotein (HDL) apolipoproteomic score, based on targeted mass spectrometry of HDL-associated apolipoproteins, for the detection of angiographic CAD and outcomes. HDL-associated apolipoprotein (apo) A-1, apoC-1, apoC-2, apoC-3, and apoC-4 were measured in 943 participants without prevalent myocardial infarction (MI) referred for coronary angiography in the CASABLANCA (Catheter Sampled Blood Archive in Cardiovascular Diseases) study. A composite HDL apolipoproteomic score (pCAD) was associated with likelihood of obstructive CAD (≥70% lesion in ≥1 vessel) and with incident cardiovascular outcomes over 4-year follow-up. There were 587 (62.2%) patients with coronary stenosis. The pCAD score was associated with the presence of obstructive CAD (odds ratio: 1.39; 95% confidence interval [CI]: 1.14 to 1.69; p < 0.001), independently of conventional cardiovascular risk factors including circulating plasma apoA-1 and apoB. The C-index for pCAD was 0.63 (95% CI: 0.59 to 0.67) for the presence of obstructive CAD. Although pCAD was not associated with cardiovascular mortality among all individuals (hazard ratio: 1.24; 95% CI: 0.93 to 1.66; p = 0.15), there was evidence of association for individuals with obstructive CAD (hazard ratio: 1.48; 95% CI: 1.07 to 2.05; p = 0.019). An HDL apolipoproteomic score is associated with the presence of CAD, independent of circulating apoA-1 and apoB concentrations and other conventional cardiovascular risk factors. Among individuals with CAD, this score may be independently associated cardiovascular death. (The CASABLANCA Study: Catheter Sampled Blood Archive in Cardiovascular Diseases [CASABLANCA]; NCT00842868). Show less

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. Show less

Pharmacological enhancers of lipoprotein lipase (LPL) are in preclinical or early clinical development for cardiovascular prevention. Studying whether these agents will reduce cardiovascular events or diabetes risk when added to existing lipid-lowering drugs would require large outcome trials. Human genetics studies can help prioritize or deprioritize these resource-demanding endeavors. To investigate the independent and combined associations of genetically determined differences in LPL-mediated lipolysis and low-density lipoprotein cholesterol (LDL-C) metabolism with risk of coronary disease and diabetes. In this genetic association study, individual-level genetic data from 392 220 participants from 2 population-based cohort studies and 1 case-cohort study conducted in Europe were included. Data were collected from January 1991 to July 2018, and data were analyzed from July 2014 to July 2018. Six conditionally independent triglyceride-lowering alleles in LPL, the p.Glu40Lys variant in ANGPTL4, rare loss-of-function variants in ANGPTL3, and LDL-C-lowering polymorphisms at 58 independent genomic regions, including HMGCR, NPC1L1, and PCSK9. Odds ratio for coronary artery disease and type 2 diabetes. Of the 392 220 participants included, 211 915 (54.0%) were female, and the mean (SD) age was 57 (8) years. Triglyceride-lowering alleles in LPL were associated with protection from coronary disease (approximately 40% lower odds per SD of genetically lower triglycerides) and type 2 diabetes (approximately 30% lower odds) in people above or below the median of the population distribution of LDL-C-lowering alleles at 58 independent genomic regions, HMGCR, NPC1L1, or PCSK9. Associations with lower risk were consistent in quintiles of the distribution of LDL-C-lowering alleles and 2 × 2 factorial genetic analyses. The 40Lys variant in ANGPTL4 was associated with protection from coronary disease and type 2 diabetes in groups with genetically higher or lower LDL-C. For a genetic difference of 0.23 SDs in LDL-C, ANGPTL3 loss-of-function variants, which also have beneficial associations with LPL lipolysis, were associated with greater protection against coronary disease than other LDL-C-lowering genetic mechanisms (ANGPTL3 loss-of-function variants: odds ratio, 0.66; 95% CI, 0.52-0.83; 58 LDL-C-lowering variants: odds ratio, 0.90; 95% CI, 0.89-0.91; P for heterogeneity = .009). Triglyceride-lowering alleles in the LPL pathway are associated with lower risk of coronary disease and type 2 diabetes independently of LDL-C-lowering genetic mechanisms. These findings provide human genetics evidence to support the development of agents that enhance LPL-mediated lipolysis for further clinical benefit in addition to LDL-C-lowering therapy. Show less

Angiopoietin-like 4 (ANGPTL4) is an endogenous inhibitor of lipoprotein lipase that modulates lipid levels, coronary atherosclerosis risk, and nutrient partitioning. We hypothesize that loss of ANGPTL4 function might improve glucose homeostasis and decrease risk of type 2 diabetes (T2D). We investigate protein-altering variants in ANGPTL4 among 58,124 participants in the DiscovEHR human genetics study, with follow-up studies in 82,766 T2D cases and 498,761 controls. Carriers of p.E40K, a variant that abolishes ANGPTL4 ability to inhibit lipoprotein lipase, have lower odds of T2D (odds ratio 0.89, 95% confidence interval 0.85-0.92, p = 6.3 × 10 Show less

We screened variants on an exome-focused genotyping array in >300,000 participants (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 showed lipid changes consistent with the human data. We also found that: (i) beta-thalassemia trait carriers displayed lower TC and were protected from coronary artery disease (CAD); (ii) excluding the CETP locus, there was not a predictable relationship between plasma HDL-C and risk for age-related macular degeneration; (iii) only some mechanisms of lowering LDL-C appeared to increase risk for type 2 diabetes (T2D); and (iv) TG-lowering alleles involved in hepatic production of TG-rich lipoproteins (TM6SF2 and PNPLA3) tracked with higher liver fat, higher risk for T2D, and lower risk for CAD, whereas TG-lowering alleles involved in peripheral lipolysis (LPL and ANGPTL4) had no effect on liver fat but decreased risks for both T2D and CAD. Show less

Therapies that inhibit CETP (cholesteryl ester transfer protein) have failed to demonstrate a reduction in risk for coronary heart disease (CHD). Human DNA sequence variants that truncate the To test whether protein-truncating variants (PTVs) at the We sequenced the exons of the Compared with noncarriers, carriers of PTV at Show less

Genome-wide association studies have so far identified 56 loci associated with risk of coronary artery disease (CAD). Many CAD loci show pleiotropy; that is, they are also associated with other diseases or traits. This study sought to systematically test if genetic variants identified for non-CAD diseases/traits also associate with CAD and to undertake a comprehensive analysis of the extent of pleiotropy of all CAD loci. In discovery analyses involving 42,335 CAD cases and 78,240 control subjects we tested the association of 29,383 common (minor allele frequency >5%) single nucleotide polymorphisms available on the exome array, which included a substantial proportion of known or suspected single nucleotide polymorphisms associated with common diseases or traits as of 2011. Suggestive association signals were replicated in an additional 30,533 cases and 42,530 control subjects. To evaluate pleiotropy, we tested CAD loci for association with cardiovascular risk factors (lipid traits, blood pressure phenotypes, body mass index, diabetes, and smoking behavior), as well as with other diseases/traits through interrogation of currently available genome-wide association study catalogs. We identified 6 new loci associated with CAD at genome-wide significance: on 2q37 (KCNJ13-GIGYF2), 6p21 (C2), 11p15 (MRVI1-CTR9), 12q13 (LRP1), 12q24 (SCARB1), and 16q13 (CETP). Risk allele frequencies ranged from 0.15 to 0.86, and odds ratio per copy of the risk allele ranged from 1.04 to 1.09. Of 62 new and known CAD loci, 24 (38.7%) showed statistical association with a traditional cardiovascular risk factor, with some showing multiple associations, and 29 (47%) showed associations at p < 1 × 10 We identified 6 loci associated with CAD at genome-wide significance. Several CAD loci show substantial pleiotropy, which may help us understand the mechanisms by which these loci affect CAD risk. Show less

Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of 195,180 individuals and identify 16 loci associated with grip strength (P<5 × 10 Show less

Understanding the physiological mechanisms by which common variants predispose to type 2 diabetes requires large studies with detailed measures of insulin secretion and sensitivity. Here we performed the largest genome-wide association study of first-phase insulin secretion, as measured by intravenous glucose tolerance tests, using up to 5,567 individuals without diabetes from 10 studies. We aimed to refine the mechanisms of 178 known associations between common variants and glycemic traits and identify new loci. Thirty type 2 diabetes or fasting glucose-raising alleles were associated with a measure of first-phase insulin secretion at Show less

A large number of genetic loci are associated with adult body mass index. However, the genetics of childhood body mass index are largely unknown. We performed a meta-analysis of genome-wide association studies of childhood body mass index, using sex- and age-adjusted standard deviation scores. We included 35 668 children from 20 studies in the discovery phase and 11 873 children from 13 studies in the replication phase. In total, 15 loci reached genome-wide significance (P-value < 5 × 10(-8)) in the joint discovery and replication analysis, of which 12 are previously identified loci in or close to ADCY3, GNPDA2, TMEM18, SEC16B, FAIM2, FTO, TFAP2B, TNNI3K, MC4R, GPR61, LMX1B and OLFM4 associated with adult body mass index or childhood obesity. We identified three novel loci: rs13253111 near ELP3, rs8092503 near RAB27B and rs13387838 near ADAM23. Per additional risk allele, body mass index increased 0.04 Standard Deviation Score (SDS) [Standard Error (SE) 0.007], 0.05 SDS (SE 0.008) and 0.14 SDS (SE 0.025), for rs13253111, rs8092503 and rs13387838, respectively. A genetic risk score combining all 15 SNPs showed that each additional average risk allele was associated with a 0.073 SDS (SE 0.011, P-value = 3.12 × 10(-10)) increase in childhood body mass index in a population of 1955 children. This risk score explained 2% of the variance in childhood body mass index. This study highlights the shared genetic background between childhood and adult body mass index and adds three novel loci. These loci likely represent age-related differences in strength of the associations with body mass index. Show less