The unfolding low-carbon transition in the UK electricity system.

The paper explores three periods in the UK electricity consumption-production system since World War II. The first two involved the development of an increasingly centralized, integrated system that provided electricity to meet growing post-war demand. It saw two major changes in governance, first to nationalization, then to privatization and liberalization. The third period started at the turn of the Century, driven by increasing evidence of the impact of fossil fuels on the Earth's climate. The paper focuses on the drivers of change, within the UK and externally, and how they affected governance, technology deployment, and industry structure. It draws on the multi-level perspective and the concepts of governance and technological branching points to inform the analysis of each period. It shows that there is a considerable distance to travel toward a truly sustainable electricity system.

Congenital chromoanagenesis in the routine postnatal chromosomal microarray analyses.

Chromosomal microarray analyses (CMA) have greatly increased both the yield and diagnostic accuracy of postnatal analysis; it has been used as a first-tier cytogenetic test in patients with intellectual disability, autism spectrum disorder, and multiple congenital abnormalities. During the last 15 years, we performed CMA in approximately 8,000 patients with neurodevelopmental and/or congenital disorders, of which 13 (0.16%) genetically catastrophic complex chromosomal rearrangements were identified. These ultrarare rearrangements showed clustering of breakpoints, characteristic of chromoanagenesis events. Al1 13 complex events display underlying formation mechanisms, originating either by a synchronization of the shattering of clustered chromosome regions in which regional asynchrony of DNA replication may be one of the main causes of disruption. We provide an overview of the copy number profiling in these patients. Although several previous studies have suggested that chromoanagenesis is often a genetic disease source in postnatal diagnostic screening, due to either the challenge of clinical interpretation of these complex rearrangements or the limitation of microarray resolution relative to the small size and complexity of chromogenic induced chromosome abnormalities, bringing further attention and to study its occurrence in the clinical setting is extremely important.

Hepatoblastomas exhibit marked NNMT downregulation driven by promoter DNA hypermethylation.

Hepatoblastomas exhibit the lowest mutational burden among pediatric tumors. We previously showed that epigenetic disruption is crucial for hepatoblastoma carcinogenesis. Our data revealed hypermethylation of nicotinamide N-methyltransferase, a highly expressed gene in adipocytes and hepatocytes. The expression pattern and the role of nicotinamide N-methyltransferase in pediatric liver tumors have not yet been explored, and this study aimed to evaluate the effect of nicotinamide N-methyltransferase hypermethylation in hepatoblastomas. We evaluated 45 hepatoblastomas and 26 non-tumoral liver samples. We examined in hepatoblastomas if the observed nicotinamide N-methyltransferase promoter hypermethylation could lead to dysregulation of expression by measuring mRNA and protein levels by real-time quantitative polymerase chain reaction, immunohistochemistry, and Western blot assays. The potential impact of nicotinamide N-methyltransferase changes was evaluated on the metabolic profile by high-resolution magic angle spinning nuclear magnetic resonance spectroscopy. Significant nicotinamide N-methyltransferase downregulation was revealed in hepatoblastomas, with two orders of magnitude lower nicotinamide N-methyltransferase expression in tumor samples and hepatoblastoma cell lines than in hepatocellular carcinoma cell lines. A specific TSS1500 CpG site (cg02094283) of nicotinamide N-methyltransferase was hypermethylated in tumors, with an inverse correlation between its methylation level and nicotinamide N-methyltransferase expression. A marked global reduction of the nicotinamide N-methyltransferase protein was validated in tumors, with strong correlation between gene and protein expression. Of note, higher nicotinamide N-methyltransferase expression was statistically associated with late hepatoblastoma diagnosis, a known clinical variable of worse prognosis. In addition, untargeted metabolomics analysis detected aberrant lipid metabolism in hepatoblastomas. Data presented here showed the first evidence that nicotinamide N-methyltransferase reduction occurs in hepatoblastomas, providing further support that the nicotinamide N-methyltransferase downregulation is a wide phenomenon in liver cancer. Furthermore, this study unraveled the role of DNA methylation in the regulation of nicotinamide N-methyltransferase expression in hepatoblastomas, in addition to evaluate the potential effect of nicotinamide N-methyltransferase reduction in the metabolism of these tumors. These preliminary findings also suggested that nicotinamide N-methyltransferase level may be a potential prognostic biomarker for hepatoblastoma.

Insight into the mechanisms and consequences of recurrent telomere capture associated with a sub-telomeric deletion.

A complex mosaicism of the short arm of chromosome 1 detected by SNP microarray analysis is described in a patient presenting a 4-Mb 1p36 terminal deletion and associated phenotypic features. The array pattern of chromosome 1p displayed an intriguing increase in divergence of the SNP heterozygote frequency from the expected 50% from the centromere towards the 1p36 breakpoint. This suggests that various overlapping segments of UPD were derived by somatic recombination between the 1p homologues. The most likely explanation was the occurrence of a series of events initiated in either a gamete or an early embryonic cell division involving a 1pter deletion rapidly followed by multiple telomere captures, resulting in additive, stepped increases in frequency of homozygosity towards the telomere. The largest segment involved the entire 1p, and at least four other capture events were observed, indicating that at least five independent telomere captures occurred in separate cell lineages. The determination of breakpoint position by detection of abrupt changes in B-allele frequency using a moving window analysis demonstrated that they were identical in blood and saliva, the tissues available for analysis. We developed a model to explain the interaction of parameters determining the mosaic clones and concluded that, while number, size, and position of telomere captures were important initiating determinants, variation in individual clone frequencies was the main contributor to mosaic differences between tissues. All previous reports of telomere capture have been restricted to single events. Other cases involving multiple telomere capture probably exist but require investigation by SNP microarrays for their detection.

Increased DNA Copy Number Variation Mosaicism in Elderly Human Brain.

Aging is a complex process strongly determined by genetics. Previous reports have shown that the genome of neuronal cells displays somatic genomic mosaicism including DNA copy number variations (CNVs). CNVs represent a significant source of genetic variation in the human genome and have been implicated in several disorders and complex traits, representing a potential mechanism that contributes to neuronal diversity and the etiology of several neurological diseases and provides new insights into the normal, complex functions of the brain. Nonetheless, the features of somatic CNV mosaicism in nondiseased elderly brains have not been investigated. In the present study, we demonstrate a highly significant increase in the number of CNVs in nondiseased elderly brains compared to the blood. In two neural tissues isolated from paired postmortem samples (same individuals), we found a significant increase in the frequency of deletions in both brain areas, namely, the frontal cortex and cerebellum. Also, deletions were found to be significantly larger when present only in the cerebellum. The sizes of the variants described here were in the 150-760 kb range, and importantly, nearly all of them were present in the Database of Genomic Variants (common variants). Nearly all evidence of genome structural variation in human brains comes from studies detecting changes in single cells which were interpreted as derived from independent, isolated mutational events. The observations based on array-CGH analysis indicate the existence of an extensive clonal mosaicism of CNVs within and between the human brains revealing a different type of variation that had not been previously characterized.

True polyploid meiosis in the human male.

Polyploidy does not usually occur in germinal cells of mammals and other higher vertebrates. We describe a unique example of mosaic autotetraploidy in the meiosis of a human male. Although the original observations were made in the late 1960s, we did not publish them at that time, because we expected to detect further examples that could be described together. However, this did not occur and we have now decided to make the observations available to demonstrate that polyploidy in mammalian male meiosis can arise at a higher frequency than expected by random polyploidization of individual meiotic cells, by either DNA duplication or cell fusion prior to synapsis. This is the first description of a population of primary spermatocytes exhibiting multivalent formation at leptotene /diakinesis in human spermatogenesis, with ring, chain, frying pan and other types of quadrivalents, typical of autotetraploidy. As many of the polyploid configurations showed apoptotic breakdown, it is likely that diploid and/or aneuploid spermatozoa would have rarely or never resulted from this mosaic autotetraploid meiosis.

Novel partial duplication of EYA1 causes branchiootic syndrome in a large Brazilian family.

OBJECTIVE: To identify novel genetic causes of syndromic hearing loss in Brazil. DESIGN: To map a candidate chromosomal region through linkage studies in an extensive Brazilian family and identify novel pathogenic variants using sequencing and array-CGH. STUDY SAMPLE: Brazilian pedigree with individuals affected by BO syndrome characterized by deafness and malformations of outer, middle and inner ear, auricular and cervical fistulae, but no renal abnormalities. RESULTS: Whole genome microarray-SNP scanning on samples of 11 affected individuals detected a multipoint Lod score of 2.6 in the EYA1 gene region (chromosome 8). Sequencing of EYA1 in affected patients did not reveal pathogenic mutations. However, oligonucleotide-array-CGH detected a duplication of 71.8Kb involving exons 4 to 10 of EYA1 (heterozygous state). Real-time-PCR confirmed the duplication in fourteen of fifteen affected individuals and absence in 13 unaffected individuals. The exception involved a consanguineous parentage and was assumed to involve a different genetic mechanism. CONCLUSIONS: Our findings implicate this EYA1 partial duplication segregating with BO phenotype in a Brazilian pedigree and is the first description of a large duplication leading to the BOR/BO syndrome.

Large germline copy number variations as predisposing factor in childhood neoplasms.

AIMS: Constitutive genetic factors are believed to predispose to cancer in children. This study investigated the role of rare germline copy number variations (CNVs) in pediatric cancer predisposition. PATIENTS & METHODS: A total of 54 patients who developed cancer in infancy were screened by array-CGH for germline CNVs. RESULTS: In total, 12 rare CNVs were detected, including a Xq27.2 triplication, and two >1.8 Mb deletions: one of them at 13q31, containing only RNA genes, and another at 3q26.33-q27.1, in a patient with congenital malformations. Detected rare CNVs are significantly larger than those identified in controls, and encompass genes never implicated in cancer predisposition. CONCLUSION: Our results suggest that constitutive CNVs contribute to the etiology of pediatric neoplasms, revealing new candidate genes for tumorigenesis.

Germline DNA copy number variation in individuals with Argyrophilic grain disease reveals CTNS as a plausible candidate gene.

Argyrophilic grain disease (AGD) is a progressive neurodegenerative disease of the human brain that has never been associated to a particular gene locus. In the present study, we report the results of a CNV investigation in 29 individuals whose anatomopathologic investigation of the brain showed AGD. Rare CNVs were identified in six patients (21%), in particular a 40 kb deletion at 17p13.2 encompassing the CTNS gene. Homozygote mutations in CTNS are known to cause cystinosis, a disorder characterized by the intralysosomal accumulation of cystine in all tissues. We present the first CNV results in individuals presenting AGD and a possible candidate gene implicated in the disorder.

Germline DNA copy number variation in familial and early-onset breast cancer.

INTRODUCTION: Genetic factors predisposing individuals to cancer remain elusive in the majority of patients with a familial or clinical history suggestive of hereditary breast cancer. Germline DNA copy number variation (CNV) has recently been implicated in predisposition to cancers such as neuroblastomas as well as prostate and colorectal cancer. We evaluated the role of germline CNVs in breast cancer susceptibility, in particular those with low population frequencies (rare CNVs), which are more likely to cause disease." METHODS: Using whole-genome comparative genomic hybridization on microarrays, we screened a cohort of women fulfilling criteria for hereditary breast cancer who did not carry BRCA1/BRCA2 mutations. RESULTS: The median numbers of total and rare CNVs per genome were not different between controls and patients. A total of 26 rare germline CNVs were identified in 68 cancer patients, however, a proportion that was significantly different (P = 0.0311) from the control group (23 rare CNVs in 100 individuals). Several of the genes affected by CNV in patients and controls had already been implicated in cancer. CONCLUSIONS: This study is the first to explore the contribution of germline CNVs to BRCA1/2-negative familial and early-onset breast cancer. The data suggest that rare CNVs may contribute to cancer predisposition in this small cohort of patients, and this trend needs to be confirmed in larger population samples.

Germline copy number variations and cancer predisposition.

We present an overview of the role of germline copy number variations (CNVs) in cancer predisposition. CNVs represent a significant source of genetic diversity, although the mechanisms by which they influence cancer susceptibility still remain largely unknown. Approximately 100 highly penetrant germline mutant genes are now known to cause cancer predisposition inherited in a Mendelian fashion; in this review, we show that nearly half of these genes have also been observed as rare CNVs associated with cancer. However, these highly penetrant alleles seem to account for less than 5% of all familial cancers. We surmise that most of the genetic risk of cancer in the general population must largely involve genes of low or moderate penetrance. In the last 5 years, studies have demonstrated that although common low penetrant CNVs are modest contributors to cancer individually, their combined impact on cancer predisposition must be taken into account in estimating cancer risk.

Chromosomal microarray analyses from 5778 patients with neurodevelopmental disorders and congenital anomalies in Brazil.

Chromosomal microarray analysis (CMA) has been recommended and practiced routinely since 2010 both in the USA and Europe as the first-tier cytogenetic test for patients with unexplained neurodevelopmental delay/intellectual disability, autism spectrum disorders, and/or multiple congenital anomalies. However, in Brazil, the use of CMA is still limited, due to its high cost and complexity in integrating the results from both the private and public health systems. Although Brazil has one of the world's largest single-payer public healthcare systems, nearly all patients referred for CMA come from the private sector, resulting in only a small number of CMA studies in Brazilian cohorts. To date, this study is by far the largest Brazilian cohort (n = 5788) studied by CMA and is derived from a joint collaboration formed by the University of São Paulo and three private genetic diagnostic centers to investigate the genetic bases of neurodevelopmental disorders and congenital abnormalities. We identified 2,279 clinically relevant CNVs in 1886 patients, not including the 26 cases of UPD found. Among detected CNVs, the corresponding frequency of each category was 55.6% Pathogenic, 4.4% Likely Pathogenic and 40% VUS. The diagnostic yield, by taking into account Pathogenic, Likely Pathogenic and UPDs, was 19.7%. Since the rational for the classification is mostly based on Mendelian or highly penetrant variants, it was not surprising that a second event was detected in 26% of those cases of predisposition syndromes. Although it is common practice to investigate the inheritance of VUS in most laboratories around the world to determine the inheritance of the variant, our results indicate an extremely low cost-benefit of this approach, and strongly suggest that in cases of a limited budget, investigation of the parents of VUS carriers using CMA should not be prioritized.

Predictors of in-hospital mortality in critically ill patients with COVID-19: a large dual tertiary centre study.

OBJECTIVES: The aim of this study was to investigate the relationship of echocardiographic parameters, laboratory findings and clinical characteristics with in-hospital mortality in adult patients with COVID-19 admitted to the intensive care units (ICU) in two large collaborating tertiary UK centres. DESIGN: Observational retrospective study. SETTING: The study was conducted in patients admitted to the ICU in two large tertiary centres in London, UK. PARTICIPANTS: Inclusion criteria were: (1) patients admitted to the ICU with a COVID-19 diagnosis over a period of 16 weeks. and (2) underwent a transthoracic echocardiogram on the first day of ICU admission as clinically indicated.No exclusion criteria applied.Three hundred patients were enrolled and completed the follow-up. PRIMARY AND SECONDARY OUTCOME MEASURES: The outcome measure in this study was in-hospital mortality in patients admitted to the ICU with COVID-19 infection. RESULTS: Older age (HR: 1.027, 95% CI 1.007 to 1.047; p=0.008), left ventricular (LV) ejection fraction<35% (HR: 5.908, 95% CI 2.609 to 13.376; p<0.001), and peak C reactive protein (CRP) (HR: 1.002, 95% CI 1.001 to 1.004, p=0.001) were independently correlated with mortality in a multivariable Cox regression model. Following multiple imputation of variables with more than 5% missing values, random forest analysis was applied to the imputed data. Right ventricular (RV) basal diameter (RVD1), RV mid-cavity diameter (RVD2), tricuspid annular plane systolic excursion, RV systolic pressure, hypertension, RV dysfunction, troponin level on admission, peak CRP, creatinine level on ICU admission, body mass index and age were found to have a high relative importance (> 0.7). CONCLUSIONS: In patients with COVID-19 in the ICU, both severely impaired LV function and impaired RV function may have adverse prognostic implications, but older age and inflammatory markers appear to have a greater impact. A combination of echocardiographic and laboratory investigations as well as demographic and clinical characteristics appears appropriate for risk stratification in patients with COVID-19 who are admitted to the ICU.

An agenda for future Social Sciences and Humanities research on energy efficiency: 100 priority research questions.

Decades of techno-economic energy policymaking and research have meant evidence from the Social Sciences and Humanities (SSH)-including critical reflections on what changing a society's relation to energy (efficiency) even means-have been underutilised. In particular, (i) the SSH have too often been sidelined and/or narrowly pigeonholed by policymakers, funders, and other decision-makers when driving research agendas, and (ii) the setting of SSH-focused research agendas has not historically embedded inclusive and deliberative processes. The aim of this paper is to address these gaps through the production of a research agenda outlining future SSH research priorities for energy efficiency. A Horizon Scanning exercise was run, which sought to identify 100 priority SSH questions for energy efficiency research. This exercise included 152 researchers with prior SSH expertise on energy efficiency, who together spanned 62 (sub-)disciplines of SSH, 23 countries, and a full range of career stages. The resultant questions were inductively clustered into seven themes as follows: (1) Citizenship, engagement and knowledge exchange in relation to energy efficiency; (2) Energy efficiency in relation to equity, justice, poverty and vulnerability; (3) Energy efficiency in relation to everyday life and practices of energy consumption and production; (4) Framing, defining and measuring energy efficiency; (5) Governance, policy and political issues around energy efficiency; (6) Roles of economic systems, supply chains and financial mechanisms in improving energy efficiency; and (7) The interactions, unintended consequences and rebound effects of energy efficiency interventions. Given the consistent centrality of energy efficiency in policy programmes, this paper highlights that well-developed SSH approaches are ready to be mobilised to contribute to the development, and/or to understand the implications, of energy efficiency measures and governance solutions. Implicitly, it also emphasises the heterogeneity of SSH policy evidence that can be produced. The agenda will be of use for both (1) those new to the energy-SSH field (including policyworkers), for learnings on the capabilities and capacities of energy-SSH, and (2) established energy-SSH researchers, for insights on the collectively held futures of energy-SSH research.

The additive value of three-dimensional derived left atrial volume and carotid imaging in dobutamine stress echocardiography.

AIMS: to evaluate whether the three-dimensional (3D) left atrial volume index (LAVI) and/or the presence of carotid plaques (CP) can predict the result of dobutamine stress echocardiography (DSE), thereby aiding interpretation. METHODS AND RESULTS: we studied 130 patients (52 male, mean age 63 ± 11 years) with normal resting wall motion (WM) undergoing DSE. All patients had the end-systolic 2D and 3D LAVI measured, as well as bilateral carotid scanning. DSE was reported as abnormal in 50 (38.5%) patients. 3D end-systolic LAVI measurements were significantly higher (31.5 ± 8.2 vs 27.4 ± 7.4 mL/m(2), P = 0.004) in those with an abnormal DSE. The two groups did not differ significantly on the 2D derived maximum LAVI measurements (36.2 ± 9.5 vs 34.2 ± 11.2, P = 0.299) and the presence of plaques in the carotid arteries (89.1 vs. 76.2%, P = 0.100). Receiver operating characteristic curves were created to define cut-offs that could predict the DSE result for the 3D LAVI. A 3D LAVI of >24.5 mL/m(2) had a sensitivity of 80% for predicting an abnormal DSE, whereas a value of >36.0 mL/m(2) had a specificity of 93% for the same cause. Intra-observer (r = 0.997, P < 0.0001) and inter-observer (r = 0.961, P < 0.0001) variability for 3D LAVI measurements was found to be excellent. CONCLUSION: three-dimensional (but not 2D) assessment of LAVI may offer additional information in predicting the result of DSE. Carotid scanning did not offer additional information for the same cause.

Two distinct regions in 2q24.2-q24.3 associated with idiopathic epilepsy.

Approximately 50% of all carriers of 2q21-q31 deletions present epileptic seizures. The band 2q24 constitutes the smallest commonly deleted segment in these patients, and contains the voltage-gated sodium channel genes SCN1A and SCN2A, associated with Dravet syndrome and benign familial neonatal-infantile seizures, respectively. A further putative locus involving epilepsy in the region was previously identified through disruption of the SLC4A10 gene by translocation. In the course of performing high-resolution DNA copy number analyses on syndromic mentally impaired individuals, we encountered three patients with overlapping deletions in chromosome region 2q24. Two of these patients exhibited epileptic seizures in addition to mental deficiency. The deletion in one of the epileptic patients did not include the SCN cluster, demonstrating that a less severe form of epilepsy maps to an adjacent genomic region. This second region comprises about 3 Mb and contains the candidate gene SLC4A10, providing further support for the potential role of this gene in epilepsy.

A novel locus for split-hand/foot malformation associated with tibial hemimelia (SHFLD syndrome) maps to chromosome region 17p13.1-17p13.3.

Split-hand/foot malformation (SHFM) associated with aplasia of long bones, SHFLD syndrome or Tibial hemimelia-ectrodactyly syndrome is a rare condition with autosomal dominant inheritance, reduced penetrance and an incidence estimated to be about 1 in 1,000,000 liveborns. To date, three chromosomal regions have been reported as strong candidates for harboring SHFLD syndrome genes: 1q42.2-q43, 6q14.1 and 2q14.2. We characterized the phenotype of nine affected individuals from a large family with the aim of mapping the causative gene. Among the nine affected patients, four had only SHFM of the hands and no tibial defects, three had both defects and two had only unilateral tibial hemimelia. In keeping with previous publications of this and other families, there was clear evidence of both variable expression and incomplete penetrance, the latter bearing hallmarks of anticipation. Segregation analysis and multipoint Lod scores calculations (maximum Lod score of 5.03 using the LINKMAP software) using all potentially informative family members, both affected and unaffected, identified the chromosomal region 17p13.1-17p13.3 as the best and only candidate for harboring a novel mutated gene responsible for the syndrome in this family. The candidate gene CRK located within this region was sequenced but no pathogenic mutation was detected.

Thiazole Orange as an Alternative to Antibody Binding for Detecting Triple-helical DNA in Heterochromatin of Drosophila and Rhynchosciara.

The standard method for detecting triple-stranded DNA over the last 1.5 decades has been immune detection using antibodies raised against non-canonical nucleic acid structures. Many fluorescent dyes bind differentially to nucleic acids and often exhibit distinctive staining patterns along metaphase chromosomes dependent upon features, including binding to the major and minor DNA grooves, level of chromatin compaction, nucleotide specificity, and level of dye stacking. Relatively recently, the fluorochrome Thiazole Orange (TO) was shown to preferentially bind to triplex DNA in gels. Here, we demonstrate that TO also detects triplex DNA in salivary gland chromosomes of Drosophila melanogaster and Rhynchosciara americana identical in location and specificity to observations using antibodies. This finding may enable triple-stranded DNA investigations to be carried out on a much broader and reproducible scale than hitherto possible using antibodies, where a frequently encountered problem is the difference in detection specificity and sensitivity between one antibody and another.

Left atrial volumetric assessment using a novel automated framework for 3D echocardiography: a multi-centre analysis.

AIMS: This study aims at validating a software tool for automated segmentation and quantification of the left atrium (LA) from 3D echocardiography. METHODS AND RESULTS: The LA segmentation tool uses a dual-chamber model of the left side of the heart to automatically detect and track the atrio-ventricular plane and the LA endocardium in transthoracic 3D echocardiography. The tool was tested in a dataset of 121 ultrasound images from patients with several cardiovascular pathologies (in a multi-centre setting), and the resulting volumes were compared with those assessed manually by experts in a blinded analysis using conventional contouring. Bland-Altman analysis showed good agreement between the automated method and the manual references, with differences (mean ± 1.96 SD) of 0.5 ± 5.7 mL for LA minimum volume and -1.6 ± 9.7 mL for LA maximum volume (comparable to the inter-observer variability of manual tracings). The automated tool required no user interaction in 93% of the recordings, while 4% required a single click and only 2% required contour adjustments, reducing considerably the amount of time and effort required for LA volumetric analysis. CONCLUSION: The automated tool was validated in a multi-centre setting, providing quantification of the LA volume over the cardiac cycle with minimal user interaction. The results of the automated analysis were in agreement with those estimated manually by experts. This study shows that such approach has clinical utility for the assessment of the LA morphology and function, automating and facilitating the time-consuming task of analysing 3D echocardiographic recordings.