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The basidiomycete Schizophyllum commune has the highest level of genetic polymorphism known among living organisms. In a previous study, it was also found to have a moderately high per generation mutation rate of 2x10-8, likely contributing to its high polymorphism. However, this rate has been measured only in an experiment on Petri dishes, and it is unclear how it translates to natural populations. Here, we used an experimental design that measures the rate of accumulation of de novo mutations in a linearly growing mycelium. We show that Sch. Commune accumulates mutations at a rate of 1.24x10-7 substitutions per nucleotide per meter of growth, or about 2.04x10-11 per nucleotide per cell division. In contrast to what has been observed in a number of species with extensive vegetative growth, this rate does not decline in the course of propagation of a mycelium. As a result, even a moderate per cell division mutation rate in Sch. Commune can translate into a very high per generation mutation rate when the number of cell divisions between consecutive eiosis is large. © The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.OBJECTIVES The long-term outcome of tetralogy of Fallot (TOF) is determined by progressive right ventricular (RV) dysfunction through pulmonary regurgitation (PR) and the risk of malignant arrhythmia. Although mechano-electrical coupling in TOF is well-known, its time effect on the inducibility of arrhythmia remains ill-defined. The goal of this study was to investigate the mechano-electrical properties at different times in animals with chronic PR. METHODS PR was induced by a transannular patch with limited RV scarring in infant pigs. Haemodynamic assessment included biventricular pressure-volume loops after 3 (n = 8) and 6 months (n = 7) compared to controls (n = 5). Scriptaid The electrophysiological study included endocardial monophasic action potential registration, intraventricular conduction velocity and induction of ventricular arrhythmia by burst pacing. RESULTS Progressive RV dilation was achieved at 6 months (RV end-diastolic volume 143 ± 13 ml/m2-RV end-systolic volume 96 ± 7 ml/m2; P  less then  0.001), inythmia after TOF repair and opens a window for renewed stratification of contemporary risk factors of ventricular arrhythmias in patients operated on with currently used pulmonary valve- and RV-related techniques. © The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.OBJECTIVES Research concerning cardiopulmonary bypass (CPB) management during minimally invasive cardiac surgery (MICS) is scarce. We investigated the effect of CPB parameters such as pump flow, haemoglobin concentration and oxygen delivery on clinical outcome and renal function in a propensity matched comparison between MICS and median sternotomy (MS) for atrioventricular valve surgery. METHODS A total of 356 patients undergoing MICS or MS for atrioventricular valve surgery between 2006 and 2017 were analysed retrospectively. Propensity score analysis matched 90 patients in the MS group with 143 in the MICS group. Logistic regression analysis was performed to investigate independent predictors of cardiac surgery-associated acute kidney injury in patients having MICS. RESULTS In MICS, CPB (142.9 ± 39.4 vs 101.0 ± 38.3 min; P  less then  0.001) and aortic cross-clamp duration (89.9 ± 30.6 vs 63.5 ± 23.0 min; P  less then  0.001) were significantly prolonged although no differences in clinical outcomes were det20. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.Fisher's fundamental theorem of natural selection predicts no additive variance of fitness in a natural population. Consistently, studies in a variety of wild populations show virtually no narrow-sense heritability (h2) for traits important to fitness. However, counterexamples are occasionally reported, calling for a deeper understanding on the evolution of additive variance. In this study we propose adaptive divergence followed by population admixture as a source of the additive genetic variance of evolutionarily important traits. We experimentally tested the hypothesis by examining a panel of ∼1,000 yeast segregants produced by a hybrid of two yeast strains that experienced adaptive divergence. We measured over 400 yeast cell morphological traits and found a strong positive correlation between h2 and evolutionary importance. Because adaptive divergence followed by population admixture could happen constantly, particularly in species with wide geographic distribution and strong migratory capacity (e.g., humans), the finding reconciles the observation of abundant additive variances in evolutionarily important traits with Fisher's fundamental theorem of natural selection. Importantly, the revealed role of positive selection in promoting rather than depleting additive variance suggests a simple explanation for why additive genetic variance can be dominant in a population despite the ubiquitous between-gene epistasis observed in functional assays. © The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.Gene duplication serves a critical role in evolutionary adaptation by providing genetic raw material to the genome. The evolution of duplicated genes may be influenced by epigenetic processes such as DNA methylation, which affects gene function in some taxa. However, the manner in which DNA methylation affects duplicated genes is not well understood. We studied duplicated genes of the honeybee Apis mellifera, an insect with a highly sophisticated social structure, to investigate whether DNA methylation was associated with gene duplication and genic evolution. We found that levels of gene body methylation were significantly lower in duplicate genes than in single copy genes, implicating a possible role of DNA methylation in post-duplication gene maintenance. Additionally, we discovered associations of gene body methylation with the location, length, and time since divergence of paralogous genes. We also found that divergence in DNA methylation was associated with divergence in gene expression in paralogs, although the relationship was not completely consistent with a direct link between DNA methylation and gene expression.

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