Loss of function,missense, and intronic variants in NOTCH1 confer different risks for left ventricular outflow tract obstructive heart defects in two European cohorts

Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes.     

Albuminuria and heart failure: is it an albuminuria or the hypertension? reply

We are grateful to Dr Parmar for raising this important issue.Dr Parmar appears to be under the impression that our studysample consisted of elderly men with hypertension.     

Identification of 22 novel loci associated with urinary biomarkers of albumin,sodium, and potassium excretion

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Inflammation, as measured by the erythrocyte sedimentation rate, is an independent predictor for the development of heart failure

OBJECTIVES: Our objective was to explore inflammation, measured as erythrocyte sedimentation rate (ESR), as a predictor for the development of heart failure (HF). BACKGROUND: In recent years, evidence of the importance of inflammation in the pathophysiology of HF has emerged, and various inflammatory markers have been found to predict future HF. Erythrocyte sedimentation rate is an inexpensive and easily accessible marker of systemic inflammation, but to this date it is unknown whether ESR predicts subsequent HF. METHODS: In a community-based prospective study of 2,314 middle-aged men free from HF, myocardial infarction, and valvular disease at baseline, ESR was analyzed in multivariable models together with established risk factors for HF (hypertension, diabetes, electrocardiographic left ventricular hypertrophy, smoking, obesity, and serum cholesterol) and hematocrit. RESULTS: A total of 282 men developed HF during a median follow-up time of 30 years. In Cox proportional hazards analyses, ESR was an independent predictor of HF (hazard ratio 1.46 for highest quartile vs. the lowest, 95% confidence interval 1.04 to 2.06). This observation remained significant when also adjusting for interim myocardial infarction during follow-up. CONCLUSIONS: Erythrocyte sedimentation rate was a significant predictor of HF, independent of established risk factors for HF, and interim myocardial infarction after three decades of follow-up in a population-based sample of middle-aged men. Our findings indicate that inflammation occurs early in the process leading to HF and that ESR could be used to evaluate this process.     

Sortilin receptor 1 predicts longitudinal cognitive change

The gene encoding sortilin receptor 1 (SORL1) has been associated with Alzheimer's disease risk. We examined 15 SORL1 variants and single nucleotide polymorphism (SNP) set risk scores in relation to longitudinal verbal, spatial, memory, and perceptual speed performance, testing for age trends and sex-specific effects. Altogether, 1609 individuals from 3 population-based Swedish twin studies were assessed up to 5 times across 16 years. Controlling for apolipoprotein E genotype (APOE), multiple simple and sex-moderated associations were observed for spatial, episodic memory, and verbal trajectories (p = 1.25E-03 to p = 4.83E-02). Five variants (rs11600875, rs753780, rs7105365, rs11820794, rs2070045) were associated across domains. Notably, in those homozygous for the rs2070045 risk allele, men demonstrated initially favorable performance but accelerating declines, and women showed overall lower performance. SNP set risk scores predicted spatial (Card Rotations, p = 5.92E-03) and episodic memory trajectories (Thurstone Picture Memory, p = 3.34E-02), where higher risk scores benefited men's versus women's performance up to age 75 but with accelerating declines. SORL1 is associated with cognitive aging, and might contribute differentially to change in men and women.     

Novel metabolic risk factors for heart failure.

OBJECTIVES: Our objectives were to explore novel metabolic risk factors for development of heart failure (HF). BACKGROUND: In the past decade, considerable knowledge has been gained from limited samples regarding novel risk factors for HF, but the importance of these in the general population is largely unexplored. METHODS: In a community-based prospective study of 2,321 middle-aged men free from HF and valvular disease at baseline, variables reflecting glucose and lipid metabolism and variables involved in oxidative processes were compared with established risk factors for HF (prior myocardial infarction, hypertension, diabetes, electrocardiographic left ventricular hypertrophy, smoking, obesity, and serum cholesterol) using Cox proportional hazards analyses. RESULTS: During a median follow-up time of 29 years, 259 subjects developed HF. In a multivariable Cox proportional hazards backward stepwise model, a 1-SD increase of fasting proinsulin (hazard ratio [HR] 1.38, 95% confidence interval [CI] 1.15 to 1.66) and apolipoprotein B/A-I-ratio (HR 1.27, 95% CI 1.09 to 1.48) increased the risk, whereas a 1-SD increase in serum beta-carotene (HR 0.79, 95% CI 0.66 to 0.94) decreased the risk of HF. These variables also remained significant when adjusting for acute myocardial infarction during follow-up. CONCLUSIONS: Novel variables reflecting insulin resistance and dyslipidemia, together with a low beta-carotene level, were found to predict HF independently of established risk factors. If confirmed, our observations could have large clinical implications, as they may offer new approaches in the prevention of HF.     

Associations of insulin resistance and type 2 diabetes to heart failure: Epidemiology, potential mechanisms, and clinical perspectives

Heart failure, a common condition in most industrialized nations, is disabling and deadly. Type 2 diabetes, recognized as a risk factor for incident heart failure more than three decades ago, consistently has been associated with a twofold to threefold increased risk of heart failure and type 2 diabetes often coexist, and several studies have shown that type 2 diabetes in heart failure patients is associated with markedly increased mortality. Insulin resistance recently was reported to be a predictor of heart failure incidence independent of established risk factors, including diabetes and obesity. This review summarizes the literature regarding the associations of insulin resistance and type 2 diabetes to heart failure, and it discusses potential mechanisms underlying these associations and clinical perspectives.     

The PPH1 phosphatase is specifically involved in LHCII dephosphorylation and state transitions in Arabidopsis

The ability of plants to adapt to changing light conditions depends on a protein kinase network in the chloroplast that leads to the reversible phosphorylation of key proteins in the photosynthetic membrane. Phosphorylation regulates, in a process called state transition, a profound reorganization of the electron transfer chain and remodeling of the thylakoid membranes. Phosphorylation governs the association of the mobile part of the light-harvesting antenna LHCII with either photosystem I or photosystem II. Recent work has identified the redox-regulated protein kinase STN7 as a major actor in state transitions, but the nature of the corresponding phosphatases remained unknown. Here we identify a phosphatase of Arabidopsis thaliana, called PPH1, which is specifically required for the dephosphorylation of light-harvesting complex II (LHCII). We show that this single phosphatase is largely responsible for the dephosphorylation of Lhcb1 and Lhcb2 but not of the photosystem II core proteins. PPH1, which belongs to the family of monomeric PP2C type phosphatases, is a chloroplast protein and is mainly associated with the stroma lamellae of the thylakoid membranes. We demonstrate that loss of PPH1 leads to an increase in the antenna size of photosystem I and to a strong impairment of state transitions. Thus phosphorylation and dephosphorylation of LHCII appear to be specifically mediated by the kinase/phosphatase pair STN7 and PPH1. These two proteins emerge as key players in the adaptation of the photosynthetic apparatus to changes in light quality and quantity.