Pervasive, conserved secondary structure in highly charged protein regions

Understanding how protein sequences confer function remains a defining challenge in molecular biology. Two approaches have yielded enormous insight yet are often pursued separately: structure-based, where sequence-encoded structures mediate function, and disorder-based, where sequences dictate physicochemical and dynamical properties which determine function in the absence of stable structure. Here we study highly charged protein regions (>40% charged residues), which are routinely presumed to be disordered. Using recent advances in structure prediction and experimental structures, we show that roughly 40% of these regions form well-structured helices. Features often used to predict disorder—high charge density, low hydrophobicity, low sequence complexity, and evolutionarily varying length—are also compatible with solvated, variable-length helices. We show that a simple composition classifier predicts the existence of structure far better than well-established heuristics based on charge and hydropathy. We show that helical structure is more prevalent than previously appreciated in highly charged regions of diverse proteomes and characterize the conservation of highly charged regions. Our results underscore the importance of integrating, rather than choosing between, structure- and disorder-based approaches

Rapid host adaptation by extensive recombination

Experimental investigations into virus recombination can provide valuable insights into the biochemical mechanisms and the evolutionary value of this fundamental biological process. Here, we describe an experimental scheme for studying recombination that should be applicable to any recombinogenic viruses amenable to the production of synthetic infectious genomes. Our approach is based on differences in fitness that generally exist between synthetic chimaeric genomes and the wild-type viruses from which they are constructed. In mixed infections of defective reciprocal chimaeras, selection strongly favours recombinant progeny genomes that recover a portion of wild-type fitness. Characterizing these evolved progeny viruses can highlight both important genetic fitness determinants and the contribution that recombination makes to the evolution of their natural relatives. Moreover, these experiments supply precise information about the frequency and distribution of recombination breakpoints, which can shed light on the mechanistic processes underlying recombination. We demonstrate the value of this approach using the small single-stranded DNA geminivirus, maize streak virus (MSV). Our results show that adaptive recombination in this virus is extremely efficient and can yield complex progeny genomes comprising up to 18 recombination breakpoints. The patterns of recombination that we observe strongly imply that the mechanistic processes underlying rolling circle replication are the prime determinants of recombination breakpoint distributions found in MSV genomes sampled from nature

Within-host evolution of Staphylococcus aureus during asymptomatic carriage

Background Staphylococcus aureus is a major cause of healthcare associated mortality, but like many important bacterial pathogens, it is a common constituent of the normal human body flora. Around a third of healthy adults are carriers. Recent evidence suggests that evolution of S. aureus during nasal carriage may be associated with progression to invasive disease. However, a more detailed understanding of within-host evolution under natural conditions is required to appreciate the evolutionary and mechanistic reasons why commensal bacteria such as S. aureus cause disease. Therefore we examined in detail the evolutionary dynamics of normal, asymptomatic carriage. Sequencing a total of 131 genomes across 13 singly colonized hosts using the Illumina platform, we investigated diversity, selection, population dynamics and transmission during the short-term evolution of S. aureus. Principal Findings We characterized the processes by which the raw material for evolution is generated: micro-mutation (point mutation and small insertions/deletions), macro-mutation (large insertions/deletions) and the loss or acquisition of mobile elements (plasmids and bacteriophages). Through an analysis of synonymous, non-synonymous and intergenic mutations we discovered a fitness landscape dominated by purifying selection, with rare examples of adaptive change in genes encoding surface-anchored proteins and an enterotoxin. We found evidence for dramatic, hundred-fold fluctuations in the size of the within-host population over time, which we related to the cycle of colonization and clearance. Using a newly-developed population genetics approach to detect recent transmission among hosts, we revealed evidence for recent transmission between some of our subjects, including a husband and wife both carrying populations of methicillin-resistant S. aureus (MRSA). Significance This investigation begins to paint a picture of the within-host evolution of an important bacterial pathogen during its prevailing natural state, asymptomatic carriage. These results also have wider significance as a benchmark for future systematic studies of evolution during invasive S. aureus disease

Identification of a BRCA2-Specific modifier locus at 6p24 related to breast cancer risk

Common genetic variants contribute to the observed variation in breast cancer risk for BRCA2 mutation carriers; those known to date have all been found through population-based genome-wide association studies (GWAS). To comprehensively identify breast cancer risk modifying loci for BRCA2 mutation carriers, we conducted a deep replication of an ongoing GWAS discovery study. Using the ranked P-values of the breast cancer associations with the imputed genotype of 1.4 M SNPs, 19,029 SNPs were selected and designed for inclusion on a custom Illumina array that included a total of 211,155 SNPs as part of a multi-consortial project. DNA samples from 3,881 breast cancer affected and 4,330 unaffected BRCA2 mutation carriers from 47 studies belonging to the Consortium of Investigators of Modifiers of BRCA1/2 were genotyped and available for analysis. We replicated previously reported breast cancer susceptibility alleles in these BRCA2 mutation carriers and for several regions (including FGFR2, MAP3K1, CDKN2A/B, and PTHLH) identified SNPs that have stronger evidence of association than those previously published. We also identified a novel susceptibility allele at 6p24 that was inversely associated with risk in BRCA2 mutation carriers (rs9348512; per allele HR = 0.85, 95% CI 0.80-0.90, P = 3.9×10−8). This SNP was not associated with breast cancer risk either in the general population or in BRCA1 mutation carriers. The locus lies within a region containing TFAP2A, which encodes a transcriptional activation protein that interacts with several tumor suppressor genes. This report identifies the first breast cancer risk locus specific to a BRCA2 mutation background. This comprehensive update of novel and previously reported breast cancer susceptibility loci contributes to the establishment of a panel of SNPs that modify breast cancer risk in BRCA2 mutation carriers. This panel may have clinical utility for women with BRCA2 mutations weighing options for medical prevention of breast cancer

Significant benefits of AIP testing and clinical screening in familial isolated and young-onset pituitary tumors

Context Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are responsible for a subset of familial isolated pituitary adenoma (FIPA) cases and sporadic pituitary neuroendocrine tumors (PitNETs). Objective To compare prospectively diagnosed AIP mutation-positive (AIPmut) PitNET patients with clinically presenting patients and to compare the clinical characteristics of AIPmut and AIPneg PitNET patients. Design 12-year prospective, observational study. Participants & Setting We studied probands and family members of FIPA kindreds and sporadic patients with disease onset ≤18 years or macroadenomas with onset ≤30 years (n = 1477). This was a collaborative study conducted at referral centers for pituitary diseases. Interventions & Outcome AIP testing and clinical screening for pituitary disease. Comparison of characteristics of prospectively diagnosed (n = 22) vs clinically presenting AIPmut PitNET patients (n = 145), and AIPmut (n = 167) vs AIPneg PitNET patients (n = 1310). Results Prospectively diagnosed AIPmut PitNET patients had smaller lesions with less suprasellar extension or cavernous sinus invasion and required fewer treatments with fewer operations and no radiotherapy compared with clinically presenting cases; there were fewer cases with active disease and hypopituitarism at last follow-up. When comparing AIPmut and AIPneg cases, AIPmut patients were more often males, younger, more often had GH excess, pituitary apoplexy, suprasellar extension, and more patients required multimodal therapy, including radiotherapy. AIPmut patients (n = 136) with GH excess were taller than AIPneg counterparts (n = 650). Conclusions Prospectively diagnosed AIPmut patients show better outcomes than clinically presenting cases, demonstrating the benefits of genetic and clinical screening. AIP-related pituitary disease has a wide spectrum ranging from aggressively growing lesions to stable or indolent disease course

Genome-Wide Association Study in BRCA1 Mutation Carriers Identifies Novel Loci Associated with Breast and Ovarian Cancer Risk

BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7×10-8, HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4×10-8, HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4×10-8, HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific associat

A collaborative approach to exploring the future of Cancer treatment and care in relation to Precision Medicine: A design perspective.

The Precision Medicine and the Future of Cancer project was jointly conceived by the Innovation School at Glasgow School of Art and the Institute of Cancer Sciences at the University of Glasgow. Graduating year Product Design students from the Innovation School were presented with a challenge-based project to produce a vision of the future based on current trends that relate to Precision Medicine(PM) and Cancer treatment. This project involved working closely with scientists, clinicians, patients, industry and academic professionals from Glasgow University, staff at Queen Elizabeth University Hospital and Clinical Innovation Zone, staff at Beatson West of Scotland Cancer Centre, Patient Representatives and external design experts from Studio AndThen and GOODD design consultancy. The objective of this project was to investigate, in both analytical and speculative ways, future forms and functions of cancer treatment and care in relation to Precision Medicine, to develop future scenarios and design artefacts, services, and the experiences associated with them. One of the most significant societal shifts currently taking place within the field of PM is the transformation around what it means to be a patient and a professional working within this context. The public’s role is developing beyond once-passive patients into stakeholders valued within the medical industry and healthcare sector for their participation in clinical trials, and contribution towards policy-making and decision-making committees. This new dynamic is changing the traditional patient-doctor relationship and challenging the hegemony of medical practice at an institutional level. The impetus for this shift is relentless technological acceleration and increased scientific research, in particular driven by advances in PM. This project asked students to consider what will happen in a cancer landscape ten years from now, where PM has evolved to the extent that new forms of medical practice, cancer treatment and care transform how we interact with each other, with professionals and the world around us. The brief gave students the opportunity to reflect on the underlying complexities regarding the future of health, technological acceleration, post-capitalism and human agency, to envision a future world context, develop it as an experiential exhibit, and produce the designed products, services and experiences for the people who might live and work within it. The project was divided into two sections: The first was a collaborative stage where groups of students were assigned a specific area of focus from Social, Technological, Economic, Ethical, Educational, Political, Legal, Ecological [STEEEPLE]. These groups focused on researching and exploring their specific lenses and gathering as much information and understanding while working with external experts to further their knowledge. This group stage culminated in an exhibition of the collaborative understanding of what the future could look like in 10 years from now, after exploring the possible consequences of current actions. The second stage saw students explore their individual response to the world that had been defined in the first stage. Each student had their own response to the research by iteratively creating a design outcome that was appropriate to the subject matter. This culminated in each student having created a design product/service/experience relating to the future scenario. A full report (Project Process Journal [PPJ]) is included within the repository of each student which breaks down their process of designing and the outcome they have designed. The project aims to tackle the emerging possibilities where medical professionals and design can collaborate, to create a future where forms of medical practice are more preventative and are more appropriate for an aging population now and into the future. The deposited materials are arranged as follows: Readme files - two readme files relate to stage one and stage two of the project as outlined above. Overview poster - gives a visual overview of the structure and timeline of the project. Data folders - the data folders for stage one of the project are named for the lens through which each group viewed possible futures. The data folders for stage two of the project are named for the individual students who conducted the work

Prevalence and patterns of hospital use for people with frequent alcohol-related hospital admissions, compared to non-alcohol and non-frequent admissions:a cohort study using routine administrative hospital data

AIMS: This study compared prevalence and hospital use among individuals frequently admitted to hospital in England with wholly attributable alcohol-related diagnoses (WAAD), known as alcohol-related frequent attenders (ARFAs), with those of non-alcohol frequent attenders (NAFAs), non-frequent alcohol attenders (ARNFAs) and non-alcohol non-frequent attenders (NANFAs). DESIGN: Cross-sectional and longitudinal analyses of 5 years of England's Hospital Episode Statistics (HES). SETTING: Hospital inpatients in England, UK, 2011-16. PARTICIPANTS: Two cohorts (2011/12 = 489 580/7 654 944 patients and 2015/16 = 490 384/7 660 108 patients) were selected from all adult patients aged ≥ 18 years, treated in English hospitals between 1 April 2011 and 31 March 2016. Patients were categorized as having alcohol-related admissions if diagnoses included a WAAD (ICD-10 classification, WHO, 2016) and frequent admissions if they had more than three hospital admissions during a single HES year. MEASUREMENTS: Prevalence of ARFA, number of admissions (spells), occupied bed-days (OBDs), average length of stay (ALOS) and total admission costs over 5 years were compared among ARFAs, ARNFAs, NAFAs and NANFAs. FINDINGS: On average, 0.7% of people admitted to hospital per annum in England 2011-15 were ARFAs and more than a quarter of all frequent attenders (for all causes) to hospitals had a wholly attributable alcohol diagnosis on admission. ARFAs had longer ALOS than the other patient groups [5.55 days versus ARNFA 4.7, NAFA 3.39 and NANFA 2.57 days, F = 1088.37 (3, 488 570, P < 0.001)] in the 2015/16 index year; but fewer spells than NAFAs [5.38 ARFAs versus 5.98 NAFAs, F = 20 536.25 (3, 490 380) P < 0.001]. The ARFA cohort reduced in size (from 51 934 ARFAs to 20 548) in the course of 5 years. ARFAs had the highest average total cost of admissions per person over 5 years at £38 189. CONCLUSIONS: People with repeated admissions for alcohol-related problems in England appear to be a high-cost, high-need, complex group of patients that makes up more than a quarter of the country's alcohol admissions

Prevalence and patterns of hospital use for people with frequent alcohol-related hospital admissions, compared to non-alcohol and non-frequent admissions: a cohort study using routine administrative hospital data.

AIMS: This study compared prevalence and hospital use among individuals frequently admitted to hospital in England with wholly attributable alcohol-related diagnoses (WAAD), known as alcohol-related frequent attenders (ARFAs), with those of non-alcohol frequent attenders (NAFAs), non-frequent alcohol attenders (ARNFAs) and non-alcohol non-frequent attenders (NANFAs). DESIGN: Cross-sectional and longitudinal analyses of 5 years of England's Hospital Episode Statistics (HES). SETTING: Hospital inpatients in England, UK, 2011-16. PARTICIPANTS: Two cohorts (2011/12 = 489 580/7 654 944 patients and 2015/16 = 490 384/7 660 108 patients) were selected from all adult patients aged ≥ 18 years, treated in English hospitals between 1 April 2011 and 31 March 2016. Patients were categorized as having alcohol-related admissions if diagnoses included a WAAD (ICD-10 classification, WHO, 2016) and frequent admissions if they had more than three hospital admissions during a single HES year. MEASUREMENTS: Prevalence of ARFA, number of admissions (spells), occupied bed-days (OBDs), average length of stay (ALOS) and total admission costs over 5 years were compared among ARFAs, ARNFAs, NAFAs and NANFAs. FINDINGS: On average, 0.7% of people admitted to hospital per annum in England 2011-15 were ARFAs and more than a quarter of all frequent attenders (for all causes) to hospitals had a wholly attributable alcohol diagnosis on admission. ARFAs had longer ALOS than the other patient groups [5.55 days versus ARNFA 4.7, NAFA 3.39 and NANFA 2.57 days, F = 1088.37 (3, 488 570, P < 0.001)] in the 2015/16 index year; but fewer spells than NAFAs [5.38 ARFAs versus 5.98 NAFAs, F = 20 536.25 (3, 490 380) P < 0.001]. The ARFA cohort reduced in size (from 51 934 ARFAs to 20 548) in the course of 5 years. ARFAs had the highest average total cost of admissions per person over 5 years at £38 189. CONCLUSIONS: People with repeated admissions for alcohol-related problems in England appear to be a high-cost, high-need, complex group of patients that makes up more than a quarter of the country's alcohol admissions