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Assessing the risk of common, complex diseases requires consideration of clinical risk factors as well as monogenic and polygenic risks, which in turn may be reflected in family history. Returning risks to individuals and providers may influence preventive care or use of prophylactic therapies for those individuals at high genetic risk.To enable integrated genetic risk assessment, the eMERGE (electronic MEdical Records and GEnomics) network is enrolling 25,000 diverse individuals in a prospective cohort study across 10 sites. The network developed methods to return cross-ancestry polygenic risk scores (PRS), monogenic risks, family history, and clinical risk assessments via a Genome Informed Risk Assessment (GIRA) report and will assess uptake of care recommendations after return of results.GIRAs include summary care recommendations for 11 conditions, education pages, and clinical laboratory reports. The return of high-risk GIRA to individuals and providers includes guidelines for care and lifestyle recommendations. Assembling the GIRA required infrastructure and workflows for ingesting and presenting content from multiple sources. Recruitment began in February 2022.Return of a novel report for communicating monogenic, polygenic, and family history based risk factors will inform the benefits of integrated genetic risk assessment for routine health care.

Chronic kidney disease (CKD) is a common complex condition associated with high morbidity and mortality. Polygenic prediction could enhance CKD screening and prevention; however, this approach has not been optimized for ancestrally diverse populations. By combining APOL1 risk genotypes with genome-wide association studies (GWAS) of kidney function, we designed, optimized and validated a genome-wide polygenic score (GPS) for CKD. The new GPS was tested in 15 independent cohorts, including 3 cohorts of European ancestry (n = 97,050), 6 cohorts of African ancestry (n = 14,544), 4 cohorts of Asian ancestry (n = 8,625) and 2 admixed Latinx cohorts (n = 3,625). We demonstrated score transferability with reproducible performance across all tested cohorts. The top 2% of the GPS was associated with nearly threefold increased risk of CKD across ancestries. In African ancestry cohorts, the APOL1 risk genotype and polygenic component of the GPS had additive effects on the risk of CKD.

BackgroundPatients with non-small-cell lung cancer (NSCLC) that is resistant to PD-1 and PD-L1 (PD[L]-1)-targeted therapy have poor outcomes. Studies suggest that radiotherapy could enhance antitumour immunity. Therefore, we investigated the potential benefit of PD-L1 (durvalumab) and CTLA-4 (tremelimumab) inhibition alone or combined with radiotherapy.MethodsThis open-label, multicentre, randomised, phase 2 trial was done by the National Cancer Institute Experimental Therapeutics Clinical Trials Network at 18 US sites. Patients aged 18 years or older with metastatic NSCLC, an Eastern Cooperative Oncology Group performance status of 0 or 1, and progression during previous PD(L)-1 therapy were eligible. They were randomly assigned (1:1:1) in a web-based system by the study statistician using a permuted block scheme (block sizes of three or six) without stratification to receive either durvalumab (1500 mg intravenously every 4 weeks for a maximum of 13 cycles) plus tremelimumab (75 mg intravenously every 4 weeks for a maximum of four cycles) alone or with low-dose (0·5 Gy delivered twice per day, repeated for 2 days during each of the first four cycles of therapy) or hypofractionated radiotherapy (24 Gy total delivered over three 8-Gy fractions during the first cycle only), 1 week after initial durvalumab-tremelimumab administration. Study treatment was continued until 1 year or until progression. The primary endpoint was overall response rate (best locally assessed confirmed response of a partial or complete response) and, along with safety, was analysed in patients who received at least one dose of study therapy. The trial is registered with ClinicalTrials.gov, NCT02888743, and is now complete.FindingsBetween Aug 24, 2017, and March 29, 2019, 90 patients were enrolled and randomly assigned, of whom 78 (26 per group) were treated. This trial was stopped due to futility assessed in an interim analysis. At a median follow-up of 12·4 months (IQR 7·8-15·1), there were no differences in overall response rates between the durvalumab-tremelimumab alone group (three [11·5%, 90% CI 1·2-21·8] of 26 patients) and the low-dose radiotherapy group (two [7·7%, 0·0-16·3] of 26 patients; p=0·64) or the hypofractionated radiotherapy group (three [11·5%, 1·2-21·8] of 26 patients; p=0·99). The most common grade 3-4 adverse events were dyspnoea (two [8%] in the durvalumab-tremelimumab alone group; three [12%] in the low-dose radiotherapy group; and three [12%] in the hypofractionated radiotherapy group) and hyponatraemia (one [4%] in the durvalumab-tremelimumab alone group vs two [8%] in the low-dose radiotherapy group vs three [12%] in the hypofractionated radiotherapy group). Treatment-related serious adverse events occurred in one (4%) patient in the durvalumab-tremelimumab alone group (maculopapular rash), five (19%) patients in the low-dose radiotherapy group (abdominal pain, diarrhoea, dyspnoea, hypokalemia, and respiratory failure), and four (15%) patients in the hypofractionated group (adrenal insufficiency, colitis, diarrhoea, and hyponatremia). In the low-dose radiotherapy group, there was one death from respiratory failure potentially related to study therapy.InterpretationRadiotherapy did not increase responses to combined PD-L1 plus CTLA-4 inhibition in patients with NSCLC resistant to PD(L)-1 therapy. However, PD-L1 plus CTLA-4 therapy could be a treatment option for some patients. Future studies should refine predictive biomarkers in this setting.FundingThe US National Institutes of Health and the Dana-Farber Cancer Institute.

INTRODUCTION: Patients with ADTKD-MUC1 have one allele producing normal mucin-1 (MUC1) and one allele producing mutant MUC1, which remains intracellular. We hypothesized that ADTKD-MUC1 patients, who have only 1 secretory-competent wild-type MUC1 allele, should exhibit decreased plasma mucin-1 (MUC1) levels. To test this hypothesis, we repurposed the serum CA15-3 assay used to measure MUC1 in breast cancer to measure plasma MUC1 levels in ADTKD-MUC1. METHODS: This cross-sectional study analyzed CA15-3 levels in a reference population of 6,850 individuals, in 85 individuals with ADTKD-MUC1, and in a control population including 135 individuals with ADTKD-UMOD and 114 healthy individuals. RESULTS: Plasma CA15-3 levels (mean ± standard deviation) were 8.6 ± 4.3 U/mL in individuals with ADTKD-MUC1 and 14.6 ± 5.6 U/mL in controls (p < 0.001). While there was a significant difference in mean CA15-3 levels, there was substantial overlap between the 2 groups. Plasma CA15-3 levels were 20 U/mL in 1/85 ADTKD-MUC1 patients, in 18% of control individuals, and in 25% of the reference population. Segregation of plasma CA15-3 levels by the rs4072037 genotype did not significantly improve differentiation between affected and unaffected individuals. CA15-3 levels were minimally affected by gender and estimated glomerular filtration rate. DISCUSSION/CONCLUSIONS: Plasma CA15-3 levels in ADTKD-MUC1 patients are approximately 40% lower than levels in healthy individuals, though there is significant overlap between groups. Further investigations need to be performed to see if plasma CA15-3 levels would be useful in diagnosis, prognosis, or assessing response to new therapies in this disorder.

Repeated testing of a population is critical for limiting the spread of the SARS-CoV-2 virus and for the safe reopening of educational institutions such as K-12 schools and colleges. Many screening efforts utilize the CDC RT-PCR based assay which targets two regions of the novel Coronavirus nucleocapsid gene. The standard approach of testing each person individually, however, poses a financial burden to these institutions and is therefore a barrier to using testing for re-opening. Pooling samples from multiple individuals into a single test is an attractive alternate approach that promises significant cost savings - however the of specificity and sensitivity of such approaches needs to be assessed prior to deployment. To this end, we conducted a pilot study to evaluate the feasibility of analyzing samples in pools of eight by the established RT-PCR assay. Participants (1,576) were recruited from amongst the Tufts University community undergoing regular screening. Each volunteer provided two swabs, one analyzed separately and the other in a pool of eight. Because the positivity rate was very low, we spiked approximately half of the pools with laboratory-generated swabs produced from known positive cases outside the Tufts testing program. The results of pooled tests had 100% correspondence with those of their respective individual tests. We conclude that pooling eight samples does not negatively impact the specificity or sensitivity of the RT-PCR assay and suggest that his approach can be utilized by institutions seeking to reduce surveillance costs.

Background: The Metastatic Breast Cancer Project is a nationwide research initiative that directly engages patients through social media and advocacy groups and seeks to empower them to share their samples and clinical information to accelerate research. Because the vast majority of patients are treated in the community setting, we sought to determine the feasibility of remotely obtaining tumor and saliva samples as well as medical records from a large cohort of metastatic breast cancer (MBC) patients who receive their care in diverse settings around the country. Methods: In collaboration with patients and advocacy groups, we developed a website to allow MBC patients across the U.S. to participate. Enrolled patients are sent a saliva kit and asked to mail back a saliva sample, which is used to extract germline DNA. We contact participants' medical providers and obtain medical records and part of their tumor biopsy. Whole exome and transcriptome sequencing is performed on tumor and germline samples. Clinically annotated genomic data are used to identify mechanisms of response and resistance to therapies. The database will be shared widely with researchers. Study updates and discoveries are shared with participants regularly. Results: In the first 8 months, 2285 MBC patients from all 50 states enrolled. 2163 (95%) completed the 16-question survey about their cancer, treatments, and demographic information. 1232 completed the online consent form permitting acquisition and analysis of medical records, tumor tissue, and saliva samples. 556 saliva samples have been received. Initial medical record and tumor sample requests have been made for patients who have provided saliva samples. To date, we have obtained medical records from 102 patients (93% success rate) and tumor samples from 32 patients (77% success rate). Whole exome and transcriptome sequencing has been successfully completed on initial samples received and is ongoing for additional samples. Conclusions: Partnering directly with patients through social media and advocacy groups enables rapid identification of thousands of patients willing to share tumors, saliva, and medical records to accelerate research. This approach allows for rapid identification of patients with rare phenotypes such as extraordinary responders, who have been challenging to identify with traditional approaches. Remote acquisition of medical records, saliva samples, and tumor tissue for patients located throughout the U.S. is feasible. Genomic analysis and medical record abstraction for these patients is underway. As data is generated, a clinically annotated database will be shared widely with the research community. Citation Format: Painter CA, Anastasio E, Krevalin M, Kim D, Larken K, Lennon N, Frank E, Winer EP, Lander ES, Golub T. The metastatic breast cancer project: Translational genomics through direct patient engagement [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-05-13.

Introduction: Circulating tumor DNA (ctDNA) offers the ability to repeatedly interrogate tumor genomic information, providing an opportunity for real-time monitoring of tumor genomic dynamics. In this study, we deeply analyzed multiple ctDNA samples collected over narrow time frames (days-to-weeks) from seven patients with metastatic triple-negative breast cancer (mTNBC), a cancer type known to have high ctDNA content. Methods: Patients with mTNBC were enrolled in a clinical trial of multi-kinase inhibitor cabozantinib, providing uniform and targeted treatment, and samples were collected day 1, day 8, then every 21 to 42 days on study. ctDNA was extracted from each plasma sample and underwent ultra-low pass whole genome sequencing (ULP-WGS; average depth 0.1x; n=42 samples), deep targeted panel sequencing (TPS) of 402 cancer-related genes with unique molecular identifier indexing (depth 10,000x; n=42 samples), and samples with tumor fraction (TFx) >10% underwent whole exome sequencing (WES; depth 200x; n=31 samples), with whole blood germline sequencing of both TPS and WES for subsequent analyses. Somatic copy number alterations (SCNAs) were identified from ULP-WGS and WES. PyClone with TPS was employed for clonal dynamic analyses. Predicted neoantigens were determined from WES using HLAthena. Results: A total of 42 total plasma samples from 7 patients (range 4-8 samples per patient) were collected at narrow time intervals, median 21 days (range 6 to 42 days) between samples. The median TFx across all samples was 18.1% (range 2.5% to 44.3%). TFx estimates were concordant when comparing orthogonal sequencing approaches (ULP-WGS, WES) and tumor fraction estimation algorithms (ichorCNA, FACETS). Despite all seven patients having ‘stable disease’ as best objective response, TFx dynamics were widely variable with TFx declining to lower limit of detection in three of seven patients. Of all samples, 31/42 (73.8%) had tumor fraction >10% and underwent WES; each patient had at least 3 samples that underwent both WES and TPS. There was strong agreement between TPS and WES: across all 31 shared samples, mutation recall in TPS versus WES (gold standard) was 95.5%. Variant allele frequency across all mutations detected in both TPS and WES was highly concordant (Pearson’s r=0.949). Clonal mutations were consistently detected across multiple samples within patients. When comparing genome-wide copy number from last to first available sample within each patient, copy number log ratios were largely stable within patients (union Pearson’s r=0.924) and there were not recurrent shifts in SCNAs across patients. Through statistical modeling of TPS data, we tracked distinct clonal populations for each patient over their sampling windows. Modeled clonal architecture in most patients revealed stable, polyclonal profiles, with important breast cancer driver alterations (e.g. TP53 and PIK3CA) recurrently presenting at high prevalence. Infrequently, we also detected emergence and expansion of clones over narrow time frames (weeks) containing acquired alterations poorly annotated in the breast cancer literature. We successfully predicted neoantigens from ctDNA WES at multiple time points in each patient, with evidence that patients acquired new mutations predicted to be ‘strong binder’ neoantigens over time on therapy. Conclusions: Analysis of serial ctDNA samples collected at narrow time intervals (days-to-weeks) provides unique insight into the dynamics of ctDNA. We demonstrate strong concordance across ctDNA sequencing appraoches. Evolving genomic features of tumor populations can be identified via ctDNA while on treatment, potentially providing real time insight for clinical decision-making. Citation Format: Daniel G Stover, Katharine A Collier, David Tallman, Juliet Forman, Sachet Shukla, Sarah Asad, Justin Rhoades, Samuel Freeman, Mathew Cherian, Sagar Sardesai, Romualdo Barroso-Sousa, Carrie Cibulskis, Niall Lennon, Gavin Ha, Sara M Tolaney, Viktor A Adalsteinsson, Zachary Weber. Modeling clonal structure over narrow time frames via circulating tumor DNA in metastatic breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD9-08.

BRAF mutations occur in approximately 10% of colorectal cancers. Although RAF inhibitor monotherapy is highly effective in BRAF-mutant melanoma, response rates in BRAF-mutant colorectal cancer are poor. Recent clinical trials of combined RAF/EGFR or RAF/MEK inhibition have produced improved efficacy, but patients ultimately develop resistance. To identify molecular alterations driving clinical acquired resistance, we performed whole-exome sequencing on paired pretreatment and postprogression tumor biopsies from patients with BRAF-mutant colorectal cancer treated with RAF inhibitor combinations. We identified alterations in MAPK pathway genes in resistant tumors not present in matched pretreatment tumors, including KRAS amplification, BRAF amplification, and a MEK1 mutation. These alterations conferred resistance to RAF/EGFR or RAF/MEK combinations through sustained MAPK pathway activity, but an ERK inhibitor could suppress MAPK activity and overcome resistance. Identification of MAPK pathway reactivating alterations upon clinical acquired resistance underscores the MAPK pathway as a critical target in BRAF-mutant colorectal cancer and suggests therapeutic options to overcome resistance. Significance: RAF inhibitor combinations represent promising approaches in clinical development for BRAF-mutant colorectal cancer. Initial characterization of clinical acquired resistance mechanisms to these regimens identified several MAPK pathway alterations driving resistance by reactivating MAPK signaling, highlighting the critical dependence of BRAF-mutant colorectal cancers on MAPK signaling and offering potential strategies to overcome resistance. Cancer Discov; 5(4); 358–67. ©2015 AACR. See related commentary by Meador and Pao, p. 348 This article is highlighted in the In This Issue feature, p. 333

Broad Genomics offers a comprehensive liquid biopsy sequencing platform designed to provide the optimal flexibility for conducting research studies in a broad range of applications including: biomarker discovery, treatment resistance monitoring, and clinical grade ctDNA profiling. By utilizing low cost, low coverage whole genome sequencing in conjunction with dual unique molecular indexed (UMI) libraries we can offer a range of analysis that allow researchers to select the most appropriate samples for whole exome profiling or for deeper coverage, higher sensitivity targeted gene panels. To date we have generated over 3000 liquid biopsy whole genome copy number profiles and purity estimates and are supporting driver projects including the Broad/IBM Cancer Resistance Project and Count Me In. The study design for the Broad/IBM effort takes advantage of the discovery potential of tissue-based sequencing combined with serial liquid biopsy analysis to elucidate resistance events by tracking clonal and subclonal populations in patient samples over time. Sourcing samples for this and other similar efforts is a major undertaking and a combination of methods for maximally broad and deep genomic profiling are required to assay patients throughout the course of care, as tumor fraction in blood fluctuates. Responding to this need, and other applications requiring increased sensitivity we have developed a high throughput, automated workflow to efficiently assay cfDNA samples with lower tumor content. Benchmarking data using healthy donor pooled cfDNA samples indicates our assay is capable of detecting > 90% of variants present at ~1% minor allele fraction with less than 1 false positive variant called per megabase. This established laboratory and analytic process forms the basis of our 2Mb, 400 gene CLIA targeted assay currently undergoing validation. Through this suite of products we hope to enable an expansion of cfDNA sequencing efforts in support of clinical and research applications. Early results from emerging studies utilizing this platform to be presented. Citation Format: Carrie Cibulskis, Brendan Blumenstiel, Matthew DeFelice, Mark Fleharty, Justin Abreu, Viktor Adalsteinsson, Laxmi Parida, Susanna Hamilton, Gad Getz, Niall Lennon. Innovations in large scale liquid biopsy analysis and the Broad/IBM Cancer Resistance Project [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 455.

Whole genome sequencing (WGS) offers the greatest potential to comprehensively and accurately identify all forms of human genetic variation. The accessibility of WGS data for diagnostic use has increased due to cost reductions in recent years, driving the need for a high quality, clinically validated offering. Our platform has completed an extensive benchmarking study of the Illumina PCR-free whole genome pipeline to establish clinical validity for the end-to-end laboratory, analytical, and computational processes. Our benchmarking study is comprehensive in nature, including measuring the precision, robustness, limits of detection for variant classes, and contamination estimates. A cohort of well-characterized reference controls and clinical samples with previously identified pathogenic variants were used to establish the performance characteristics of our clinical WGS test, which at 30X coverage has >99% analytical sensitivity for SNVs and >98% analytical sensitivity for small insertions and deletions. Our platform is capable of operating at a scale that supports applications from individual clinics (cancer and medical genetics related applications) as well as large scale ambitious collaborative projects such as the All Of Us program which aims to generate clinical grade whole genome variant calls for 1 million healthy research participants. Citation Format: Alyssa MacBeth, Tera Bowers, Betty Woolf, Maegan Harden, Niall Lennon, Stacey Gabriel. Clinical whole genome sequencing at scale [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3543.

Despite rapid technical progress and demonstrable effectiveness for some types of diagnosis and therapy, much remains to be learned about clinical genome and exome sequencing (CGES) and its role within the practice of medicine. The Clinical Sequencing Exploratory Research (CSER) consortium includes 18 extramural research projects, one National Human Genome Research Institute (NHGRI) intramural project, and a coordinating center funded by the NHGRI and National Cancer Institute. The consortium is exploring analytic and clinical validity and utility, as well as the ethical, legal, and social implications of sequencing via multidisciplinary approaches; it has thus far recruited 5,577 participants across a spectrum of symptomatic and healthy children and adults by utilizing both germline and cancer sequencing. The CSER consortium is analyzing data and creating publically available procedures and tools related to participant preferences and consent, variant classification, disclosure and management of primary and secondary findings, health outcomes, and integration with electronic health records. Future research directions will refine measures of clinical utility of CGES in both germline and somatic testing, evaluate the use of CGES for screening in healthy individuals, explore the penetrance of pathogenic variants through extensive phenotyping, reduce discordances in public databases of genes and variants, examine social and ethnic disparities in the provision of genomics services, explore regulatory issues, and estimate the value and downstream costs of sequencing. The CSER consortium has established a shared community of research sites by using diverse approaches to pursue the evidence-based development of best practices in genomic medicine.

Analogous to observations in RNA viruses such as human immunodeficiency virus, genetic variation associated with intrahost dengue virus (DENV) populations has been postulated to influence viral fitness and disease pathogenesis. Previous attempts to investigate intrahost genetic variation in DENV characterized only a few viral genes or a limited number of full-length genomes. We developed a whole-genome amplification approach coupled with deep sequencing to capture intrahost diversity across the entire coding region of DENV-2. Using this approach, we sequenced DENV-2 genomes from the serum of 22 Nicaraguan individuals with secondary DENV infection and captured ∼75% of the DENV genome in each sample (range, 40 to 98%). We identified and quantified variants using a highly sensitive and specific method and determined that the extent of diversity was considerably lower than previous estimates. Significant differences in intrahost diversity were detected between genes and also between antigenically distinct domains of the Envelope gene. Interestingly, a strong association was discerned between the extent of intrahost diversity in a few genes and viral clade identity. Additionally, the abundance of viral variants within a host, as well as the impact of viral mutations on amino acid encoding and predicted protein function, determined whether intrahost variants were observed at the interhost level in circulating Nicaraguan DENV-2 populations, strongly suggestive of purifying selection across transmission events. Our data illustrate the value of high-coverage genome-wide analysis of intrahost diversity for high-resolution mapping of the relationship between intrahost diversity and clinical, epidemiological, and virological parameters of viral infection.

A variety of microbial communities and their genes (the microbiome) exist throughout the human body, with fundamental roles in human health and disease. The National Institutes of Health (NIH)-funded Human Microbiome Project Consortium has established a population-scale framework to develop metagenomic protocols, resulting in a broad range of quality-controlled resources and data including standardized methods for creating, processing and interpreting distinct types of high-throughput metagenomic data available to the scientific community. Here we present resources from a population of 242 healthy adults sampled at 15 or 18 body sites up to three times, which have generated 5,177 microbial taxonomic profiles from 16S ribosomal RNA genes and over 3.5 terabases of metagenomic sequence so far. In parallel, approximately 800 reference strains isolated from the human body have been sequenced. Collectively, these data represent the largest resource describing the abundance and variety of the human microbiome, while providing a framework for current and future studies.

West Nile virus (WNV) has become firmly established in northeastern US, reemerging every summer since its introduction into North America in 1999. To determine whether WNV overwinters locally or is reseeded annually, we examined the patterns of viral lineage persistence and replacement in Connecticut over 10 consecutive transmission seasons by phylogenetic analysis. In addition, we compared the full protein coding sequence among WNV isolates to search for evidence of convergent and adaptive evolution. Viruses sampled from Connecticut segregated into a number of well-supported subclades by year of isolation with few clades persisting ≥ 2 years. Similar viral strains were dispersed in different locations across the state and divergent strains appeared within a single location during a single transmission season, implying widespread movement and rapid colonization of virus. Numerous amino acid substitutions arose in the population but only one change, V → A at position 159 of the envelope protein, became permanently fixed. Several instances of parallel evolution were identified in independent lineages, including one amino acid change in the NS4A protein that appears to be positively selected. Our results suggest that annual reemergence of WNV is driven by both reintroduction and local-overwintering of virus. Despite ongoing evolution of WNV, most amino acid variants occurred at low frequencies and were transient in the virus population.

Nature 547, 217–221 (2017); doi:10.1038/nature22991 In this Letter, the ‘Data availability’ section in the Methods should state ‘WES and RNA-seq data are deposited in dbGaP (https://www.ncbi.nlm.nih.gov/projects/gap/cgi-bin/study.cgi?study_id=phs001451.v1.p1). All other data are available from the corresponding author upon reasonable request.

Resistance mutations to hepatitis C virus (HCV) nonstructural protein 3 (NS3) protease inhibitors in1% of the viral quasispecies may still allow1000-fold viral load reductions upon treatment, consistent with their reported reduced replicative fitness in vitro. Recently, however, an R155K protease mutation was reported as the dominant quasispecies in a treatment-naïve individual, raising concerns about possible full drug resistance. To investigate the prevalence of dominant resistance mutations against specifically targeted antiviral therapy for HCV (STAT-C) in the population, we analyzed HCV genome sequences from 507 treatment-naïve patients infected with HCV genotype 1 from the United States, Germany, and Switzerland. Phylogenetic sequence analysis and viral load data were used to identify the possible spread of replication-competent, drug-resistant viral strains in the population and to infer the consequences of these mutations upon viral replication in vivo. Mutations described to confer resistance to the protease inhibitors Telaprevir, BILN2061, ITMN-191, SCH6 and Boceprevir; the NS5B polymerase inhibitor AG-021541; and to the NS4A antagonist ACH-806 were observed mostly as sporadic, unrelated cases, at frequencies between 0.3% and 2.8% in the population, including two patients with possible multidrug resistance. Collectively, however, 8.6% of the patients infected with genotype 1a and 1.4% of those infected with genotype 1b carried at least one dominant resistance mutation. Viral loads were high in the majority of these patients, suggesting that drug-resistant viral strains might achieve replication levels comparable to nonresistant viruses in vivo.Naturally occurring dominant STAT-C resistance mutations are common in treatment-naïve patients infected with HCV genotype 1. Their influence on treatment outcome should further be characterized to evaluate possible benefits of drug resistance testing for individual tailoring of drug combinations when treatment options are limited due to previous nonresponse to peginterferon and ribavirin.

BACKGROUND: The RTS,S/AS01 vaccine targets the circumsporozoite protein of Plasmodium falciparum and has partial protective efficacy against clinical and severe malaria disease in infants and children. We investigated whether the vaccine efficacy was specific to certain parasite genotypes at the circumsporozoite protein locus. METHODS: We used polymerase chain reaction-based next-generation sequencing of DNA extracted from samples from 4985 participants to survey circumsporozoite protein polymorphisms. We evaluated the effect that polymorphic positions and haplotypic regions within the circumsporozoite protein had on vaccine efficacy against first episodes of clinical malaria within 1 year after vaccination. RESULTS: In the per-protocol group of 4577 RTS,S/AS01-vaccinated participants and 2335 control-vaccinated participants who were 5 to 17 months of age, the 1-year cumulative vaccine efficacy was 50.3% (95% confidence interval [CI], 34.6 to 62.3) against clinical malaria in which parasites matched the vaccine in the entire circumsporozoite protein C-terminal (139 infections), as compared with 33.4% (95% CI, 29.3 to 37.2) against mismatched malaria (1951 infections) (P=0.04 for differential vaccine efficacy). The vaccine efficacy based on the hazard ratio was 62.7% (95% CI, 51.6 to 71.3) against matched infections versus 54.2% (95% CI, 49.9 to 58.1) against mismatched infections (P=0.06). In the group of infants 6 to 12 weeks of age, there was no evidence of differential allele-specific vaccine efficacy. CONCLUSIONS: These results suggest that among children 5 to 17 months of age, the RTS,S vaccine has greater activity against malaria parasites with the matched circumsporozoite protein allele than against mismatched malaria. The overall vaccine efficacy in this age category will depend on the proportion of matched alleles in the local parasite population; in this trial, less than 10% of parasites had matched alleles. (Funded by the National Institutes of Health and others.).

The rapid spread of dengue is a worldwide public health problem. In two clinical studies of dengue in Managua, Nicaragua, we observed an abrupt increase in disease severity across several epidemic seasons of dengue virus serotype 2 (DENV-2) transmission. Waning DENV-1 immunity appeared to increase the risk of severe disease in subsequent DENV-2 infections after a period of cross-protection. The increase in severity coincided with replacement of the Asian/American DENV-2 NI-1 clade with a new virus clade, NI-2B. In vitro analyses of viral isolates from the two clades and analysis of viremia in patient blood samples support the emergence of a fitter virus in later, relative to earlier, epidemic seasons. In addition, the NI-1 clade of viruses was more virulent specifically in children who were immune to DENV-1, whereas DENV-3 immunity was associated with more severe disease among NI-2B infections. Our data demonstrate that the complex interaction between viral genetics and population dynamics of serotype-specific immunity contributes to the risk of severe dengue disease. Furthermore, this work provides insights into viral evolution and the interaction between viral and immunological determinants of viral fitness and virulence.

Infection with genotype 4 of the Hepatitis C virus is common in Africa and the Mediterranean area, but has also been found at increasing frequencies in injection drug users in Europe and North America. Full length viral sequences to characterize viral diversity and structure have recently become available mostly for subtype 4a, and studies in Egypt and Saudi Arabia, where high proportions of subtype 4a infected patients exist, have begun to establish optimized treatment regimens. However knowledge about other subtype variants of genotype 4 present in less developed African states is lacking. In this study the full coding region from so far poorly characterized variants of HCV genotype 4 was amplified and sequenced using a long range PCR technique. Sequences were analyzed with respect to phylogenetic relationship, possible recombination and prominent sequence characteristics compared to other known HCV strains. We present for the first time two full-length sequences from the HCV genotype 4k, in addition to five strains from HCV genotypes 4d and 4f. Reference sequences for accurate HCV genotyping are required for optimized treatment, and a better knowledge of the global viral sequence diversity is needed to guide vaccines or new drugs effective in the world wide epidemic.

Mutations in the dysferlin gene cause limb girdle muscular dystrophy type 2B and Miyoshi myopathy. We report here the results of expression profile analyses and in vitro investigations that point to an interaction between dysferlin and the Ca2+ and lipid-binding proteins, annexins A1 and A2, and define a role for dysferlin in Ca2+-dependent repair of sarcolemmal injury through a process of vesicle fusion. Expression profiling identified a network of genes that are co-regulated in dysferlinopathic mice. Co-immunofluorescence, co-immunoprecipitation, and fluorescence lifetime imaging microscopy revealed that dysferlin normally associates with both annexins A1 and A2 in a Ca2+ and membrane injury-dependent manner. The distribution of the annexins and the efficiency of sarcolemmal wound-healing are significantly disrupted in dysferlin-deficient muscle. We propose a model of muscle membrane healing mediated by dysferlin that is relevant to both normal and dystrophic muscle and defines the annexins as potential muscular dystrophy genes.

Familial amyotrophic lateral sclerosis (ALS)-linked mutations in the copper-zinc superoxide dismutase (SOD1) gene cause motor neuron death in about 3% of ALS cases. While the wild-type (wt) protein is anti-apoptotic, mutant SOD1 promotes apoptosis. We now demonstrate that both wt and mutant SOD1 bind the anti-apoptotic protein Bcl-2, providing evidence of a direct link between SOD1 and an apoptotic pathway. This interaction is evident in vitro and in vivo in mouse and human spinal cord. We also demonstrate that in mice and humans, Bcl-2 binds to high molecular weight SDS-resistant mutant SOD1 containing aggregates that are present in mitochondria from spinal cord but not liver. These findings provide new insights into the anti-apoptotic function of SOD1 and suggest that entrapment of Bcl-2 by large SOD1 aggregates may deplete motor neurons of this anti-apoptotic protein.