Genomic Balancing Act: Deciphering DNA rearrangements in the Complex Chromosomal Aberration involving 5p15.2, 2q31.1 and 18q21.32

Despite extensive research into the genetic underpinnings of neurodevelopmental disorders (NDD), many clinical cases remain unresolved. We studied a female proband with a NDD, mildly dysmorphic facial features, and brain stem hypoplasia on neuroimaging. Comprehensive genomic analyses revealed a terminal 5p loss and terminal 18q gain in the proband while a diploid copy number for chromosomes 5 and 18 in both parents. Genomic investigations in the proband identified an unbalanced translocation t(5;18) with additional genetic material from chromosome 2 (2q31.3) inserted at the breakpoint, pointing to a complex chromosomal rearrangement (CCR) involving 5p15.2, 2q31.3, and 18q21.32. Breakpoint junction analyses enabled by long read genome sequencing unveiled the presence of four distinct junctions in the father, who is carrier of a balanced CCR. The proband inherited from the father both the abnormal chromosome 5 resulting in segmental aneusomies of chr5 (loss) and chr18 (gain) and a der(2) homologue. Evidences suggest a chromoplexy mechanism for this CCR derivation, involving double-strand breaks (DSBs) repaired by non-homologous end joining (NHEJ) or alternative end joining (alt-EJ). The complexity of the CCR and the segregation of homologues elucidate the genetic model for this family. This study demonstrates the importance of combining multiple genomic technologies to uncover genetic causes of complex neurodevelopmental syndrome and to better understand genetic disease mechanisms.

Tryptophan Metabolites And Their Predicted Microbial Sources In Fecal Samples From Healthy Individuals

Gut microbiota produce tryptophan metabolites (TMs) important to homeostasis. However, measuring TM levels in stool and determining their microbial sources can be difficult. Here, we measured TMs from the indole pathway in fecal samples from 21 healthy adults with the goal to: 1) determine fecal TM concentrations in healthy individuals; 2) link TM levels to bacterial abundance using 16S and whole genome shotgun (WGS) sequencing data; and 3) predict likely bacterial sources of TM production. Within our samples, we identified 151 genera (16S) and 592 bacterial species (WGS). Eight TMs were found in ≥17 fecal samples, including four in all persons. To our knowledge, we are the first to report fecal levels for indole-3-lactate, indole-3-propionate, and 3-indoleacrylate levels in healthy persons. Overall, indole, indole-3-acetate (IAA), and skatole accounted for 86% of the eight TMs measured. Significant correlations were found between seven TMs and 29 bacterial species.  Predicted multiple TM sources support the notion of a complex network of TM production and regulation. Further, the data suggest key roles for Collinsella aerofaciens and IAA, a metabolite reported to maintain intestinal homeostasis through enhanced barrier integrity and anti-inflammatory/antioxidant activities. These findings extend our understanding of TMs and their relationship to the microbial species that act as effectors and/or regulators in the healthy intestine and may lead to novel strategies designed to manipulate tryptophan metabolism to prevent disease and/or restore health to the dysbiotic gut.

Deleterious heteroplasmic mitochondrial mutations are associated with an increased risk of overall and cancer-specific mortality

Mitochondria carry their own circular genome and disruption of the mitochondrial genome is associated with various aging-related diseases. Unlike the nuclear genome, mitochondrial DNA (mtDNA) can be present at 1000 s to 10,000 s copies in somatic cells and variants may exist in a state of heteroplasmy, where only a fraction of the DNA molecules harbors a particular variant. We quantify mtDNA heteroplasmy in 194,871 participants in the UK Biobank and find that heteroplasmy is associated with a 1.5-fold increased risk of all-cause mortality. Additionally, we functionally characterize mtDNA single nucleotide variants (SNVs) using a constraint-based score, mitochondrial local constraint score sum (MSS) and find it associated with all-cause mortality, and with the prevalence and incidence of cancer and cancer-related mortality, particularly leukemia. These results indicate that mitochondria may have a functional role in certain cancers, and mitochondrial heteroplasmic SNVs may serve as a prognostic marker for cancer, especially for leukemia.

Patient Reported Outcome Measures Used to Assess Quality of Life in Aortic Dissection: a Systematic Scoping Review using COSMIN Methodology

OBJECTIVE

To systematically identify all patient reported outcome measures (PROMs) (quality of life [QOL] instruments or other instrument/methodology) that have been used to date in aortic dissection (AD) and to explore how well these instruments evaluate QOL according to the Consensus based Standards for the selection of health Measurement Instruments (COSMIN) methodology or guideline.

DATA SOURCES

Embase, MEDLINE, PsycINFO, CINAHL, and Cochrane Library were search on 1st July 2022.

REVIEW METHODS

This scoping review was undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR) and the COSMIN guidelines for performing systematic reviews of validated PROMs. Studies that reported on any aspect or domain of QOL using a PROM or other instrument or methodology on AD were included. Data synthesis, including psychometric property analysis and risk of bias assessment were performed according to COSMIN guidelines.

RESULTS

Forty-five studies, published between 1994 and 2021 reporting on 5 874 patients (mean age 63 years, 70.6% male), were included. A total of 39 PROMs were used, and three studies used semi-structured interviews. The majority (69%) of studies were in patients with type A aortic dissection (TAAD). The most common PROM used was the SF-36 (51%). Six studies evaluated one or more psychometric properties of a PROM. Only one of these studies was specifically designed as a validation study. No study reported on content validity. Internal consistency was the most evaluated psychometric property. No study evaluated all the psychometric properties according to COSMIN methodology. The methodological quality used to assess these PROMs was judged to be adequate or very good.

CONCLUSION

This review highlights the heterogeneity of PROMs or methods used to determine QOL in AD patients. The lack of research regarding a comprehensive evaluation of the psychometric properties of a PROM used in AD highlights the need for the development and validation of a dissection specific PROM. [PROSPERO registration no. CRD42022310477].

Genetic control of mRNA splicing as a potential mechanism for incomplete penetrance of rare coding variants

Exonic variants present some of the strongest links between genotype and phenotype. However, these variants can have significant inter-individual pathogenicity differences, known as variable penetrance. In this study, we propose a model where genetically controlled mRNA splicing modulates the pathogenicity of exonic variants. By first cataloging exonic inclusion from RNA-sequencing data in GTEx V8, we find that pathogenic alleles are depleted on highly included exons. Using a large-scale phased whole genome sequencing data from the TOPMed consortium, we observe that this effect may be driven by common splice-regulatory genetic variants, and that natural selection acts on haplotype configurations that reduce the transcript inclusion of putatively pathogenic variants, especially when limiting to haploinsufficient genes. Finally, we test if this effect may be relevant for autism risk using families from the Simons Simplex Collection, but find that splicing of pathogenic alleles has a penetrance reducing effect here as well. Overall, our results indicate that common splice-regulatory variants may play a role in reducing the damaging effects of rare exonic variants.

Outcomes After Endovascular Aortic Intervention in Patients With Connective Tissue Disease

IMPORTANCE

Endovascular treatment is not recommended for aortic pathologies in patients with connective tissue diseases (CTDs) other than in redo operations and as bridging procedures in emergencies. However, recent developments in endovascular technology may challenge this dogma.

OBJECTIVE

To assess the midterm outcomes of endovascular aortic repair in patients with CTD.

DESIGN, SETTING, AND PARTICIPANTS

For this descriptive retrospective study, data on demographics, interventions, and short-term and midterm outcomes were collected from 18 aortic centers in Europe, Asia, North America, and New Zealand. Patients with CTD who had undergone endovascular aortic repair from 2005 to 2020 were included. Data were analyzed from December 2021 to November 2022.

EXPOSURE

All principal endovascular aortic repairs, including redo surgery and complex repairs of the aortic arch and visceral aorta.

MAIN OUTCOMES AND MEASURES

Short-term and midterm survival, rates of secondary procedures, and conversion to open repair.

RESULTS

In total, 171 patients were included: 142 with Marfan syndrome, 17 with Loeys-Dietz syndrome, and 12 with vascular Ehlers-Danlos syndrome (vEDS). Median (IQR) age was 49.9 years (37.9-59.0), and 107 patients (62.6%) were male. One hundred fifty-two (88.9%) were treated for aortic dissections and 19 (11.1%) for degenerative aneurysms. One hundred thirty-six patients (79.5%) had undergone open aortic surgery before the index endovascular repair. In 74 patients (43.3%), arch and/or visceral branches were included in the repair. Primary technical success was achieved in 168 patients (98.2%), and 30-day mortality was 2.9% (5 patients). Survival at 1 and 5 years was 96.2% and 80.6% for Marfan syndrome, 93.8% and 85.2% for Loeys-Dietz syndrome, and 75.0% and 43.8% for vEDS, respectively. After a median (IQR) follow-up of 4.7 years (1.9-9.2), 91 patients (53.2%) had undergone secondary procedures, of which 14 (8.2%) were open conversions.

CONCLUSIONS AND RELEVANCE

This study found that endovascular aortic interventions, including redo procedures and complex repairs of the aortic arch and visceral aorta, in patients with CTD had a high rate of early technical success, low perioperative mortality, and a midterm survival rate comparable with reports of open aortic surgery in patients with CTD. The rate of secondary procedures was high, but few patients required conversion to open repair. Improvements in devices and techniques, as well as ongoing follow-up, may result in endovascular treatment for patients with CTD being included in guideline recommendations.

Longitudinal host transcriptional responses to SARS-CoV-2 infection in adults with extremely high viral load

Current understanding of viral dynamics of SARS-CoV-2 and host responses driving the pathogenic mechanisms in COVID-19 is rapidly evolving. Here, we conducted a longitudinal study to investigate gene expression patterns during acute SARS-CoV-2 illness. Cases included SARS-CoV-2 infected individuals with extremely high viral loads early in their illness, individuals having low SARS-CoV-2 viral loads early in their infection, and individuals testing negative for SARS-CoV-2. We could identify widespread transcriptional host responses to SARS-CoV-2 infection that were initially most strongly manifested in patients with extremely high initial viral loads, then attenuating within the patient over time as viral loads decreased. Genes correlated with SARS-CoV-2 viral load over time were similarly differentially expressed across independent datasets of SARS-CoV-2 infected lung and upper airway cells, from both in vitro systems and patient samples. We also generated expression data on the human nose organoid model during SARS-CoV-2 infection. The human nose organoid-generated host transcriptional response captured many aspects of responses observed in the above patient samples, while suggesting the existence of distinct host responses to SARS-CoV-2 depending on the cellular context, involving both epithelial and cellular immune responses. Our findings provide a catalog of SARS-CoV-2 host response genes changing over time.

Carbon dioxide flushing versus saline flushing of thoracic aortic stents (INTERCEPTevar): protocol for a multicentre pilot randomised controlled trial

INTRODUCTION

Thoracic endovascular aortic repair (TEVAR) carries a 3%-6.1% stroke risk, including risk of 'silent' cerebral infarction (SCI). Stent-grafts are manufactured in room air and retain air. Instructions for use recommend saline flushing to 'de-air' the system prior to insertion, but substantial amounts of air are released when deploying them, potentially leading to downstream neuronal injury and SCI. Carbon dioxide (CO2) is more dense and more soluble in blood than air, without risk of bubble formation, so could be used in addition to saline to de-air stents. This pilot trial aims to assess the feasibility of a full-scale randomised controlled trial (RCT) investigating the neuroprotective benefit against SCI with the use of CO2-flushed aortic stent-grafts.

METHODS AND ANALYSIS

This is a multicentre pilot RCT, which is taking place in vascular centres in the UK, USA and New Zealand. Patients identified for TEVAR will be enrolled after informed written consent. 120 participants will be randomised (1:1) to TEVAR-CO2 or TEVAR-saline, stratified according to TEVAR landing zone. Participants will undergo preoperative neurocognitive tests and quality of life assessments, which will be repeated at 6 weeks, or first outpatient appointment, and 6 months. Inpatient neurological testing will be performed within 48 hours of return to level 1 care for clinical stroke or delirium. Diffusion-weighted MRI will be undertaken within 72 hours postoperatively (1-7 days) and at 6 months to look for evidence and persistence of SCI. Feasibility will be assessed via measures of recruitment and retention, informing the design of a full-scale trial.

ETHICS AND DISSEMINATION

The study coordination centre has obtained approval from the London Fulham Research Ethics Committee (19/LO/0836) and Southern Health and Disability Ethics Committee (NZ) and UK's Health Regulator Authority (HRA). The study has received ethical approval for recruitment in the UK (Fulham REC, 19/LO/0836), New Zealand (21/STH/192) and the USA (IRB 019-264, Ref 378630). Consent for entering into the study will be taken using standardised consent forms by the local study team, led by a local PI. The results of the trial will be submitted for publication in an open access journal.

TRIAL REGISTRATION NUMBER

NCT03886675.

Identification of allele-specific KIV-2 repeats and impact on Lp(a) measurements for cardiovascular disease risk

The abundance of Lp(a) protein holds significant implications for the risk of cardiovascular disease (CVD), which is directly impacted by the copy number (CN) of KIV-2, a 5.5 kbp sub-region. KIV-2 is highly polymorphic in the population and accurate analysis is challenging. In this study, we present the DRAGEN KIV-2 CN caller, which utilizes short reads. Data across 166 WGS show that the caller has high accuracy, compared to optical mapping and can further phase ~50% of the samples. We compared KIV-2 CN numbers to 24 previously postulated KIV-2 relevant SNVs, revealing that many are ineffective predictors of KIV-2 copy number. Population studies, including USA-based cohorts, showed distinct KIV-2 CN, distributions for European-, African-, and Hispanic-American populations and further underscored the limitations of SNV predictors. We demonstrate that the CN estimates correlate significantly with the available Lp(a) protein levels and that phasing is highly important.

Abstract P5-02-36: Proteogenomic profiling of fresh frozen core biopsies from CALGB 40601

Background: Targeted therapy for HER2+ breast cancer has significantly improved outcomes for this aggressive subtype. However, a subset of patients do not achieve pathological complete response (pCR). In CALGB 40601, a randomized Phase III Trial for neoadjuvant treatment of HER2+ primary breast cancer with Paclitaxel (T: taxane) combined with HER2 antibody therapy (H: Herceptin/Trastuzumab), the small molecule inhibitor Lapatinib (L), or the antibody-inhibitor combination, pCR frequency was 56% for the combination (THL arm), 46% for Trastuzumab (TH arm), and 32% for Lapatinib (TL arm, closed early because of lower efficacy) (PMID: 26527775). While a recent publication reports relapse-free survival (RFS), overall survival (OS), and RNA-based gene expression signatures that can predict pCR (PMID: 33095682), understanding the proteogenomic landscape of treatment response should facilitate identification of alternative and therapeutically tractable protein targets for treatment-resistant tumors. Methods: Microscaled proteogenomic profiling (PMID: 31988290) was performed on treatment-naïve, flash-frozen core needle biopsies from the CALGB 40601 trial obtained from the Alliance for Clinical Trials in Oncology tissue bank. Multi-omics profiling included whole-exome sequencing (WES), RNA-sequencing, and mass spectroscopy-based proteomics and phosphoproteomics from one or two cores from each patient. Results: Eighty baseline core biopsies from 54 patients, including 22 patients from the THL arm, 24 from the TH arm, and 8 from the TL arm, from the CALGB 40601 tissue archive were of sufficient quality to yield genomics, transcriptomics, and/or proteomics profiling data. The frequency of pCR for profiled samples was representative of the overall trial cohort. Linear models were employed to identify baseline determinants of pCR for each arm and to assess differences in genes associated with response between the TH and THL arms. Pathways associated with RNA processing, translation, and the proteasome were elevated in pCR tumors in TH and THL arms, while cell cycle, DNA replication and repair pathways were higher in pCR only in the THL arm. While enrichment of similar pathways was observed in pCR in the transcriptome, the proteome specifically showed enrichment of pathways associated with extracellular matrix and EMT in non-pCR in the THL but not the TH arm. In particular, “EMT”, “ECM-receptor interaction”, and “extracellular structure organization” constituted the most enriched pathways and GO terms that were higher in non-pCR than in pCR tumors from the combination arm (THL) in the proteomics data despite showing no enrichment in the transcriptomics data. Driving this pathway enrichment were several collagens and matrix metalloproteinases that were significantly elevated in non-pCR tumors at the protein but not the RNA level. Finally, kinase target enrichment of differential phosphorylation sites suggested that the activity of PAK1, a regulator of cytoskeletal remodeling, is elevated in non-pCR tumors from the THL arm (p=0.006), but not the TH arm (p=0.69). Conclusion: Proteogenomic analysis of archival HER2+ breast cancer core biopsies provides opportunities for identifying proteins and phosphorylation sites in treatment-naive tumors that are associated with pCR to neoadjuvant Paclitaxel/anti-HER2 therapy. Notably, proteomic but not transcriptomic data showed that ECM and EMT pathways were elevated in non-pCR tumors; thus, signatures encompassing these pathways may serve as biomarkers for aggressive HER2+ breast cancer that is more likely to evade treatment. Non-pCR tumors in the THL arm were also marked by elevated levels of PAK1 target phosphorylation sites, suggesting that this kinase may be a potential therapeutic target in HER2+ breast cancer that is refractory to combination anti-HER2 therapy.

Citation Format: Eric J. Jaehnig, Aranzazu Fernandez-Martinez, Tanmayi Vashist, Matthew V. Holt, LaTerrica Williams, Jonathan Lei, Beom-Jun Kim, Yongchao Dou, Viktoriya Korchina, Richard Gibbs, Donna Muzny, Harshavardhan Doddapaneni, Henry Rodriguez, Ana Robles, Tara Hiltke, DR Mani, Michael Gillette, Terry Hyslop, Yujia Wen, Linda McCart, George Miles, Steven Carr, Bing Zhang, Shankha Satpathy, Matthew Ellis, Meenakshi Anurag. Proteogenomic profiling of fresh frozen core biopsies from CALGB 40601 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-02-36.

Genetic control of mRNA splicing as a potential mechanism for incomplete penetrance of rare coding variants

Exonic variants present some of the strongest links between genotype and phenotype. However, these variants can have significant inter-individual pathogenicity differences, known as variable penetrance. In this study, we propose a model where genetically controlled mRNA splicing modulates the pathogenicity of exonic variants. By first cataloging exonic inclusion from RNA-seq data in GTEx v8, we find that pathogenic alleles are depleted on highly included exons. Using a large-scale phased WGS data from the TOPMed consortium, we observe that this effect may be driven by common splice-regulatory genetic variants, and that natural selection acts on haplotype configurations that reduce the transcript inclusion of putatively pathogenic variants, especially when limiting to haploinsufficient genes. Finally, we test if this effect may be relevant for autism risk using families from the Simons Simplex Collection, but find that splicing of pathogenic alleles has a penetrance reducing effect here as well. Overall, our results indicate that common splice-regulatory variants may play a role in reducing the damaging effects of rare exonic variants.

xAtlas: scalable small variant calling across heterogeneous next-generation sequencing experiments

BACKGROUND

The growing volume and heterogeneity of next-generation sequencing (NGS) data complicate the further optimization of identifying DNA variation, especially considering that curated high-confidence variant call sets frequently used to validate these methods are generally developed from the analysis of comparatively small and homogeneous sample sets.

FINDINGS

We have developed xAtlas, a single-sample variant caller for single-nucleotide variants (SNVs) and small insertions and deletions (indels) in NGS data. xAtlas features rapid runtimes, support for CRAM and gVCF file formats, and retraining capabilities. xAtlas reports SNVs with 99.11% recall and 98.43% precision across a reference HG002 sample at 60× whole-genome coverage in less than 2 CPU hours. Applying xAtlas to 3,202 samples at 30× whole-genome coverage from the 1000 Genomes Project achieves an average runtime of 1.7 hours per sample and a clear separation of the individual populations in principal component analysis across called SNVs.

CONCLUSIONS

xAtlas is a fast, lightweight, and accurate SNV and small indel calling method. Source code for xAtlas is available under a BSD 3-clause license at https://github.com/jfarek/xatlas.

Whole genome sequence analysis of blood lipid levels in >66,000 individuals

Blood lipids are heritable modifiable causal factors for coronary artery disease. Despite well-described monogenic and polygenic bases of dyslipidemia, limitations remain in discovery of lipid-associated alleles using whole genome sequencing (WGS), partly due to limited sample sizes, ancestral diversity, and interpretation of clinical significance. Among 66,329 ancestrally diverse (56% non-European) participants, we associate 428M variants from deep-coverage WGS with lipid levels; ~400M variants were not assessed in prior lipids genetic analyses. We find multiple lipid-related genes strongly associated with blood lipids through analysis of common and rare coding variants. We discover several associated rare non-coding variants, largely at Mendelian lipid genes. Notably, we observe rare LDLR intronic variants associated with markedly increased LDL-C, similar to rare LDLR exonic variants. In conclusion, we conducted a systematic whole genome scan for blood lipids expanding the alleles linked to lipids for multiple ancestries and characterize a clinically-relevant rare non-coding variant model for lipids.

The All of Us Research Program: Data quality, utility, and diversity

The All of Us Research Program seeks to engage at least one million diverse participants to advance precision medicine and improve human health. We describe here the cloud-based Researcher Workbench that uses a data passport model to democratize access to analytical tools and participant information including survey, physical measurement, and electronic health record (EHR) data. We also present validation study findings for several common complex diseases to demonstrate use of this novel platform in 315,000 participants, 78% of whom are from groups historically underrepresented in biomedical research, including 49% self-reporting non-White races. Replication findings include medication usage pattern differences by race in depression and type 2 diabetes, validation of known cancer associations with smoking, and calculation of cardiovascular risk scores by reported race effects. The cloud-based Researcher Workbench represents an important advance in enabling secure access for a broad range of researchers to this large resource and analytical tools.

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The All of Us Research Program has released data for over 315,000 participants

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Demonstration projects support the utility and validity of the All of Us dataset

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The cloud-based Researcher Workbench provides secure, low-cost compute power

The engagement of participants in the research process and broad availability of data to diverse researchers are essential elements in building precision medicine equitably available for all. The NIH has established the ambitious All of Us Research Program to build one of the most diverse health databases in history with tools to support research to improve human health. Here, we present the initial launch of the Researcher Workbench with data types including surveys, physical measurements, and electronic health record data with validation studies to support researcher use of this novel platform. Broad access for researchers to data like these is a critical step in returning value to participants seeking to support the advancement of precision medicine and improved health for all.

O094 Novel technique and cohort study: Stoppa approach to sciatic notch clearance in locally advanced / recurrent pelvic cancer pelvic cancer

Introduction

Locally advanced / recurrent pelvic cancers (LARC) extending into the greater sciatic notch represent a significant clinical challenge. Conventional surgical resection is associated with high rates of R1/2 resection, while locoregional oncological treatments often fail to control the disease. In this study we present the first report of a modified Stoppa approach that facilitates en bloc excision of pelvic sidewall structures with LARC.

Methods

This is a retrospective review of patients who underwent surgery for LARC with the novel Stoppa approach between 2016 and 2020 in our centre.

Result

7 patients (6 female and 1 male) were identified from the institutional database with Median age of 66 (37–74). Three separate tumour types were included in the cohort: rectal adenocarcinoma - 4 (57%), anal squamous cell carcinoma - 2 (29%), and prostate adenocarcinoma - 1 (14%). 3 (42%) patients developed Clavien Dindo Class III complications (2 returned to theatre for minor flap revisions; 1 pre-sacral collection required radiological drainage). All patients lost active ipsilateral foot dorsiflexion due to planned nerve root transection. Median hospital stay was 46 days (17–114). All resections were R0.

Conclusion

This is the first report of a novel Stoppa approach for en bloc pelvic sidewall excision. The presented pathological resection results are promising; however, this procedure is associated with significant morbidity. Future studies will be necessary to confirm the presented oncological results and determine if the associated morbidity can be decreased.

Take-home message

Modified Stoppa technique is feasible to achieve Sciatic Notch tumour clearance in primary or recurrent locally advanced pelvic cancer. Further research needed to assess long term oncological outcome and reduce post operative morbidity.

O024 Prognostic value of haemodynamic parameters in predicting adverse clinical events in type B aortic dissection

Introduction

Ascertain the prognostic role of in-vivo 4D-flow magnetic resonance imaging (MRI) and computational fluid dynamics (CFD) aortic haemodynamic parameters as predictors of adverse dissection-related events in type B aortic dissection (TBAD).

Methods

A systematic literature search was conducted according to the PRISMA guidelines using electronic databases searched from 1946 to 2021 for studies reporting on the relationship between aortic haemodynamics and aortic dissection-related events defined as aortic growth, aneurysm development, false lumen thrombosis, need for surgery and aortic rupture.

Results

Fourteen studies were included; eleven studies used CFD and three studies used 4D-flow MRI. Two studies found increased FL ejection fraction (EF) significantly associated with aortic growth rate, and another study found increased FL stroke volume significantly associated with increased aortic expansion rate. Result for time-averaged wall shear stress (TAWSS) and relative residence time (RRT) are contradictory; one study found TAWSS significantly associated with aortic wall deformation, but another study found no significant difference. Five studies suggested possible associations between slow flowing regions or increased RRT and FL thrombosis, with another study finding significant associations between FL thrombosis and adverse aortic outcomes. However, one study revealed opposite findings where decreased RRT significantly correlated with aneurysm formation.

Conclusion

In-vivo aortic haemodynamic measurements such as FL EF, FL stroke volume, TAWSS and RRT show possible associations with FL and aortic expansion, as well as FL thrombosis. Larger prospective studies are now needed to determine the prognostic utility of in vivo aortic haemodynamic metrics in predicting TBAD clinical outcomes to guide management.

Take-home message

Aortic haemodynamic parameters measured by 4D-flow magnetic resonance imaging and computational fluid dynamics show promising potential as predictors of adverse dissection-related events in type B aortic dissection.

Abstract CT026: The effect of intrinsic subtype on inhibition of tumor growth by anastrozole vs. fulvestrant vs. the combination: Results from the Alliance neoadjuvant endocrine therapy (NET) ALTERNATE trial

Introduction: The ALTERNATE trial randomized postmenopausal women with ER Allred 6-8 HER2- breast cancer to 6 months of NET with anastrozole (A), fulvestrant (F) or the combination (A+F). Biopsies were taken preNET and after 4-weeks(wks). Patients with Ki67 values >10% at 4-wks were offered triage to neoadjuvant chemotherapy. Patients with on-treatment Ki67 ≤ 10% who completed NET underwent surgery and Ki67 was reassessed. The primary endpoint was endocrine-sensitive disease rate (ESDR). ESD is defined as pCR or PEPI-0 residual disease (pT1-2, pN0, Ki67 ≤ 2.7%). We previously reported that the ESDR difference between the F-containing arms and the A arm was not >10% (ASCO 2020) and that baseline RNA-seq-based intrinsic subtypes predicted outcomes overall (SABCS 2021). Herein we describe relationships between PAM50 intrinsic subtype and Ki67 values by treatment arm because comparative drug effectiveness in adjuvant endocrine therapy studies in ER+ HER2- breast cancer can be predicted by the degree of Ki67 suppression (PMC3518447).

Methods: 743 of the 1297 eligible patients (A: 264; F: 231; A+F: 248) had RNA extracted from preNET frozen tumor biopsies with >50% tumor content and subjected to RNA seq. Intrinsic subtypes were then assigned as LumA, LumB, and NonLum (Basal or HER2-E) using open-source PAM50-based informatics. Differences in the proportion with wk4 Ki67 > 10%, % change in wk4 ki67, and surgical CCCA (Ki67 ≤ 2.7%) rate (sxCCCA) between treatments and by intrinsic subtype was assessed using stratified logistic regression, Wilcoxon rank sum test, and Fisher’s exact test, respectively. Analysis of sxCCCA excluded those who failed to complete NET for reasons other than disease progression or early Ki67 >10%.

Results: Amongst the 358 LumA cases there were no significant differences in Ki67-based endpoints between treatments. Among the 292 LumB cases, the wk4 ki67 > 10% rate was lower with A+F (19.4%) than A (43%) (P=0.0002) and was somewhat lower in F (31%) versus A (P=0.076). The % change in wk4 Ki67 in LumB cases, adjusted for baseline Ki67, showed markedly superior suppression for A+F versus A (-90% vs. -77%; P=<0.0001) and versus F (-90% vs. -80%; P=0.0026). Furthermore sxCCCA rates were significantly higher with A+F than A (53% vs. 25% P = <0.0001) and somewhat higher for F (37%) than A (p=0.068), indicating that superior antiproliferative effects for A+F persist after 6 months on therapy. Lack of Ki67 suppression in response to treatment was observed in the majority of 43 NonLum samples regardless of treatment.

Conclusion: The combination of A+F was significantly more effective than either drug alone for the control of LumB breast cancer cell proliferation. This suggests that A+F may be a more effective adjuvant endocrine therapy than A alone in LumB disease. The lower Ki67 suppression with A alone also suggests that poorer outcome in some LumB tumors may be due to insufficient ER targeting rather than ER-independent tumor growth

Support: U10CA180821, U10CA180882, U24CA196171, UG1CA189856, U10CA180868 (NRG), NCI BIQSFP, BCRF, Genentech, AstraZeneca. https://acknowledgments.alliancefound.org. (MJE) CPRIT RR140033, P50-CA186784, P50-CA58223, U01-CA214125, U24-CA210954, Gift from Ralph and Lisa Eads, McNair Scholarship.

ClinicalTrials.gov Identifier: NCT01953588

Citation Format: Matthew J. Ellis, Meenakshi Anurag, Jeremy Hoog, Aranzazu Fernandez-Martinez, Cheng Fan, Richard Gibbs, Souzan Sanati, Kiran Vij, Mark Watson, Travis Dockter, Olwen Hahn, Joseph Guenther, Abigail Caudle, Erica Crouch, Amy Tiersten, Monica Mita, Wajeeha Razaq, Tina J. Hieken, Yang Wang, A. Marilyn Leitch, Gary W. Unzeitig, Eric Winer, Anna Weiss, Kelly Hunt, Ann H. Partridge, Charles M. Perou, Vera Suman, Cynthia X. Ma, Lisa A. Carey. The effect of intrinsic subtype on inhibition of tumor growth by anastrozole vs. fulvestrant vs. the combination: Results from the Alliance neoadjuvant endocrine therapy (NET) ALTERNATE trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT026.

Abstract PD9-03: Pam50 intrinsic subtype and risk of recurrence score (ROR) for the prediction of endocrine (ET) sensitivity and pathologic response to chemotherapy in postmenopausal women with clinical stage II/III estrogen receptor positive (ER+) and HER2 negative (HER2-) breast cancer (BC) in the alternate trial (Alliance A011106)

Background: Neoadjuvant ET (NET) offers an opportunity to assess ET sensitivity for ER+ HER2- BC and potentially to tailor therapy. Ki67 >10% on biopsy after 2-4 weeks (wks) of NET identifies patients (pts) with intrinsic ET resistance; while pathologic complete response (pCR) and modified preoperative endocrine prognostic index of 0 (mPEPI 0: pT1-2N0, Ki67 ≤2.7%) at surgery indicates sensitivity to ET. However, on-NET biopsy is not always acceptable or feasible and delays the ET sensitivity determination. PAM50 ROR score and intrinsic subtypes by tumor RNA profiling are prognostic in pts with early stage ER+ HER2- BC, and predict pCR rates to neoadjuvant chemotherapy (NCT) (PMC2667820). We therefore hypothesized that PAM50 analysis on pre-NET biopsies could predict the likelihood of a) a high on-NET Ki67, b) mPEPI-0 or pCR at surgery and, c) pCR for pts triaged to NCT. Methods: The ALTERNATE trial is a phase III study that randomized postmenopausal pts with clinical stage II/III ER+ (Allred score 6-8) HER2- BC to receive neoadjuvant anastrozole, fulvestrant, or both for 6 months before surgery. Research biopsy was required at pre-NET and wk 4, then optional at wk 12. Pts with Ki67 >10% on biopsy at wk 4 or 12 discontinued NET and were offered NCT. PAM50 intrinsic subtype and ROR-P values were generated from mRNA sequencing (RNASeq) analysis on pre-NET biopsies using open-source informatics (PMC7723687) and evaluated for prediction of on-NET Ki67 >10% at wk 4 or 12, pCR or mPEPI-0 post NET, and pCR post NCT. Results: 749 of 1,297 eligible trial pts were included in the analyses, after excluding 548 pts due to insufficient pre-NET tumor for RNASeq (n=511) or PAM50 normal subtype (n=37). Similar to the entire ALTERNATE population, the rate of Ki67 >10% at wk 4 or 12 was 24.4% (95% CI: 21.4-27.7%) and the rate of mPEPI-0/pCR post NET was 19.8% (95% CI: 17.0-22.8%). There were 393 (52.5%) Lum A, 302 (40.3%) Lum B, and 54 (7.2%) non-Lum (9 Basal, 45 HER2-E) BCs. These included 196 (26.2%) ROR-P low, 354 (47.3%) ROR-P medium and 199 (26.6%) ROR-P high BCs. Both the rates of Ki67 >10% at wk 4 or 12 and mPEPI-0/pCR differed significantly with respect to PAM50 subtype or ROR-P category, such that Lum A or ROR-P low BCs were least likely to have a Ki67 >10% at wk 4 or 12 and most likely to achieve mPEPI-0/pCR (Table).

93 of 168 (55.4%) pts triaged to NCT had RNA-seq results, yielding 26 Lum A, 49 Lum B, 4 Basal and 14 HER2-E, with the pCR rates of 0%, 6.1%, 0%, and 21.4%, respectively. There were 10 ROR-P low, 39 medium, and 44 high tumors, with a pCR rate of 0%, 5.1% and 9.1%, respectively. Conclusion: These data indicate that both baseline ROR-P and intrinsic subtype are predictive of early on-NET Ki67 > 10% and mPEPI 0/pCR at surgery after NET. For pts triaged to NCT based on an early on-NET Ki67 >10%, the HER2-E group had the highest pCR rate (20%) and no pCRs were observed in Lum A. These data may be useful for directing neoadjuvant therapy in postmenopausal pts with ER+ HER2- BC. Support: U10CA180821, U10CA180882, U24CA196171, UG1CA189856, U10CA180868 (NRG), NCI BIQSFP, BCRF, Genentech, AstraZeneca. https://acknowledgments.alliancefound.org. (MJE) CPRIT RR140033, P50CA186784, P50-CA58223, U01 CA214125, U24CA210954, Gift from Ralph and Lisa Eads, McNair Scholarship. Trials.gov Identifier: NCT01953588.

Table 1.Rates of Ki67 >10% and mPEPI-0/pCR post NET by PAM50 subtype and ROR-P categoryKi67 >10% at wk 4 or 12mPEPI 0/pCR post NETPAM50 SubtypenYes, n (%)PnNo, n (%)PLum A37251 (13.7%) 95% CI: 10.4-17.6%<0.0001393104 (26.5%) 95%CI: 22.2-31.1%<0.0001Lum B29394 (32.1%) 95% CI: 26.8-37.8%30243 (14.2%) 95%CI: 10.5-18.7%Non-luminal (Basal and HER2-E)5338 (71.7%) 95%CI: 57.6-83.2%541 (1.9%) 95%CI: 0.05-9.9%ROR-P CategorynYes, n (%)PnNo, n (%)PLow18018 (10.0%) 95%CI: 6.0-15.3%<0.000119660 (30.6%) 95%CI: 24.2-37.6%<0.0001Intermediate34474 (21.5%) 95%CI: 17.3-26.2%35471 (20.1%) 95%CI: 16.0-24.6%High19491 (46.9%) 95%CI: 39.7-54.2%19917 (8.5%) 95%CI: 5.1-13.3%

Citation Format: Cynthia X Ma, Meenakshi Anurag, Travis Dockter, Jeremy Hoog, Aranzazu Fernandez-Martinez, Cheng Fan, Richard Gibbs, Souzan Sanati, Kiran Vij, Mark Watson, Olwen Hahn, Joseph Guenther, Abigail Caudle, Erika Crouch, Amy Tiersten, Monica Mita, Wajeeha Razaq, Tina J Hieken, Yang Wang, A. Marilyn Leitch, Gary W Unzeitig, Anna Weiss, Eric P Winer, Kelly Hunt, Ann H Partridge, Lisa A Carey, Charles M Perou, Matthew J Ellis, Vera Suman. Pam50 intrinsic subtype and risk of recurrence score (ROR) for the prediction of endocrine (ET) sensitivity and pathologic response to chemotherapy in postmenopausal women with clinical stage II/III estrogen receptor positive (ER+) and HER2 negative (HER2-) breast cancer (BC) in the alternate trial (Alliance A011106) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD9-03.

595 Penetrating Pelvic Trauma from a Crossbow Bolt: An Unusual Choice of Weapon

Introduction

The crossbow was a popular weapon in medieval times due to their relative ease of use and accuracy but was superseded by firearms around the 16th century. Today, it is legal for adults in the UK to own a crossbow without a licence.

Case Report

A young adult male victim was brought to a Major Trauma Centre with a single lower left quadrant penetrating wound caused a crossbow bolt that was self-removed immediately after the injury. A 2.5cm entry wound was present with no exit wound. The patient was haemodynamically unstable on arrival and was transferred to theatre without imaging within 16 minutes of arrival. The main operative findings were multiple small bowel serosal tears, a full thickness small bowel injury with no contamination and a left external iliac artery injury with active bleeding which were all repaired primarily. The post-operative recovery course included occlusive left cephalic and antecubital vein thrombi and an extensive non-occlusive left common femoral vein thrombus treated with anticoagulant therapy but was otherwise unremarkable. He was discharged 10 days later with no lasting sequelae at 6-week follow up.

Discussion

This case highlights a rare but important and likely underreported modality of penetrating injury. Crossbow bolts have low kinetic energy compared to bullets but high penetrative force, thus little energy is transferred to surrounding tissues. Hence the main injuries caused by crossbow bolts are due to direct damage to structures they come into contact with. Although rare, trauma surgeons should be aware of the pattern of injury caused by crossbows.

muCNV: Genotyping Structural Variants for Population-level Sequencing

MOTIVATION

There are high demands for joint genotyping of structural variations with short-read sequencing, but efficient and accurate genotyping in population scale is a challenging task.

RESULTS

We developed muCNV that aggregates per-sample summary pileups for joint genotyping of > 100,000 samples. Pilot results show very low Mendelian inconsistencies. Applications to large-scale projects in cloud show the computational efficiencies of muCNV genotyping pipeline.

AVAILABILITY

muCNV is publicly available for download at: https://github.com/gjun/muCNV.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Sequencing of 53,831 diverse genomes from the NHLBI TOPMed Program

The Trans-Omics for Precision Medicine (TOPMed) programme seeks to elucidate the genetic architecture and biology of heart, lung, blood and sleep disorders, with the ultimate goal of improving diagnosis, treatment and prevention of these diseases. The initial phases of the programme focused on whole-genome sequencing of individuals with rich phenotypic data and diverse backgrounds. Here we describe the TOPMed goals and design as well as the available resources and early insights obtained from the sequence data. The resources include a variant browser, a genotype imputation server, and genomic and phenotypic data that are available through dbGaP (Database of Genotypes and Phenotypes)1. In the first 53,831 TOPMed samples, we detected more than 400 million single-nucleotide and insertion or deletion variants after alignment with the reference genome. Additional previously undescribed variants were detected through assembly of unmapped reads and customized analysis in highly variable loci. Among the more than 400 million detected variants, 97% have frequencies of less than 1% and 46% are singletons that are present in only one individual (53% among unrelated individuals). These rare variants provide insights into mutational processes and recent human evolutionary history. The extensive catalogue of genetic variation in TOPMed studies provides unique opportunities for exploring the contributions of rare and noncoding sequence variants to phenotypic variation. Furthermore, combining TOPMed haplotypes with modern imputation methods improves the power and reach of genome-wide association studies to include variants down to a frequency of approximately 0.01%.

Whole exome sequencing in a large pedigree with DCM identifies a novel mutation in RBM20

Background: Familial dilated cardiomyopathy (DCM) is genetically heterogeneous and is associated with mutations in at least 40 different genes. Apart from TTN encoding the giant protein Titin, none of these genes have an expected diagnostic yield of more than 5% complicating genetic diagnosis. Whole exome sequencing (WES) is a powerful alternative for the identification of the causal gene, however variant interpretation remains challenging. We report on WES in a large family with autosomal dominant DCM complicated by end stage heart failure and non-sustained ventricular arrhythmias in whom no causative mutation was identified using a targeted gene panel including 28 genes.Methods and results: WES was applied on 2 affected cousins. Stringent filtering of the identified genetic variants was performed including population variant frequencies, in silico analysis, orthologous and paralogous conservation. Subsequently Sanger sequencing was performed for 10 potential disease causing variants in order to confirm the presence of the variant and to evaluate co-segregation. Only one variant in exon 9 of the RBM20 gene (c.2714T > A, p.Met950Lys, NM_001334363) showed full co-segregation in the 7 affected family members resulting in a maximum 2-point LOD score of 2.1 and suggesting this as the pathogenic mutation responsible for the phenotype. Recently mutations in RBM20 have been linked to arrhythmogenic dilated cardiomyopathy caused by defective splicing of the giant sarcomere protein titin and abnormal calcium handling.Conclusions: We report the identification of a novel mutation in RBM20 by WES in a large pedigree with DCM.

Community-based recruitment and exome sequencing indicates high diagnostic yield in adults with intellectual disability

BACKGROUND

Establishing a genetic diagnosis for individuals with intellectual disability (ID) benefits patients and their families as it may inform the prognosis, lead to appropriate therapy, and facilitate access to medical and supportive services. Exome sequencing has been successfully applied in a diagnostic setting, but most clinical exome referrals are pediatric patients, with many adults with ID lacking a comprehensive genetic evaluation.

METHODS

Our unique recruitment strategy involved partnering with service and education providers for individuals with ID. We performed exome sequencing and analysis, and clinical variant interpretation for each recruited family.

RESULTS

All five families enrolled in the study opted-in for the return of genetic results. In three out of five families exome sequencing analysis identified pathogenic or likely pathogenic variants in KANSL1, TUSC3, and MED13L genes. Families discussed the results and any potential medical follow-up in an appointment with a board certified clinical geneticist.

CONCLUSION

Our study suggests high yield of exome sequencing as a diagnostic tool in adult patients with ID who have not undergone comprehensive sequencing-based genetic testing. Research studies including an option of return of results through a genetic clinic could help minimize the disparity in exome diagnostic testing between pediatric and adult patients with ID.

Free-ranging horse management in Australia, New Zealand and the United States: socio-ecological dimensions of a protracted environmental conflict

Management of free-ranging horses (Equus ferus caballus) is a complex socio-ecological issue in Australia (AU), New Zealand (NZ), and the United States (US). In these countries, horses are the results of colonial introductions and occupy very harsh rangeland environments exerting a grazing disturbance that has generated ecological concerns. Although many social and ecological concerns are similar, each country also has nuances. In 2018, we conducted a field-based comparison of AU, NZ, and US using an inductive approach to identify similarities, differences, and emerging themes through conversations with >100 individuals from New South Wales Australia, the North Island of New Zealand, and the western US. Additional data sources included field observations and archival documents. Consistent emergent themes identified included: strong public emotion, politicization of management, population growth concerns, negative ecological impact concerns, agreement that horses should be treated humanely, disagreement as to what practices were the most humane, interest and scepticism about fertility control, the need for transparency, compromise to accommodating horses and acknowledgement of social values, and recognition that collaboration is the only means to achieve both healthy rangelands and healthy horses. Unique themes identified included: NZ empowering advocate groups to become part of the solution, conflict between horses and livestock is a mostly US conflict, equids originated in the US, concern about the sustainability of adoption programs, different expectations/options for management on private lands, cultural history such as brumby running in AU, permanent branding of horses in the US, litigation as a uniquely US strategy (although a judgement on recent AU litigation is pending), government data accepted to guide removals in NZ but not always in AU or US, and complex heterogeneous land surface ownership patterns makes management difficult in the US. The difficulty of horse management in these countries is attributed to social intricacies rather than biological/ecological gaps of knowledge.

A diagnostic ceiling for exome sequencing in cerebellar ataxia and related neurological disorders

Genetic ataxias are associated with mutations in hundreds of genes with high phenotypic overlap complicating the clinical diagnosis. Whole-exome sequencing (WES) has increased the overall diagnostic rate considerably. However, the upper limit of this method remains ill-defined, hindering efforts to address the remaining diagnostic gap. To further assess the role of rare coding variation in ataxic disorders, we reanalyzed our previously published exome cohort of 76 predominantly adult and sporadic-onset patients, expanded the total number of cases to 260, and introduced analyses for copy number variation and repeat expansion in a representative subset. For new cases (n = 184), our resulting clinically relevant detection rate remained stable at 47% with 24% classified as pathogenic. Reanalysis of the previously sequenced 76 patients modestly improved the pathogenic rate by 7%. For the combined cohort (n = 260), the total observed clinical detection rate was 52% with 25% classified as pathogenic. Published studies of similar neurological phenotypes report comparable rates. This consistency across multiple cohorts suggests that, despite continued technical and analytical advancements, an approximately 50% diagnostic rate marks a relative ceiling for current WES-based methods and a more comprehensive genome-wide assessment is needed to identify the missing causative genetic etiologies for cerebellar ataxia and related neurodegenerative diseases.

Rare variants in SLC5A10 are associated with serum 1,5-anhydroglucitol (1,5-AG) in the Atherosclerosis Risk in Communities (ARIC) Study

Serum 1,5-anhydroglucitol (1,5-AG) is an emerging biomarker used to monitor glycemic control in persons with diabetes. We performed whole-exome sequencing, examining the association between rare, coding genetic variants and 1,5-AG among European ancestry (N = 6,589) and African ancestry (N = 2,309) participants without diagnosed diabetes in the Atherosclerosis Risk in Communities (ARIC) Study. Five variants representing 3 independent signals on chromosome 17 in SLC5A10, a glucose transporter not previously known to transport 1,5-AG, were associated with 1,5-AG levels up to 10.38 µg/mL lower per allele (1,5-AG range 3.4–32.8 µg/mL) in the European ancestry sample and validated in the African ancestry sample. Together these variants explained 6% of the variance in 1,5-AG. Two of these variants (rs61741107, p = 8.85E-56; rs148178887, p = 1.13E-36) were rare, nonsynonymous, and predicted to be damaging or deleterious by multiple algorithms. Gene-based SKAT-O analysis supported these results (SLC5A10 p = 5.13E-64 in European ancestry, validated in African ancestry, p = 0.006). Interestingly, these novel variants are not associated with other biomarkers of hyperglycemia or diabetes (p > 0.2). The large effect sizes and protein-altering, multiple independent signals suggest SLC5A10 may code for an important transporter of 1,5-AG in the kidney, with a potential nonglucose-related effect on 1,5-AG, impacting its clinical utility as a diabetes biomarker in this subpopulation.

Prevalence of spinocerebellar ataxia 36 in a US population

Objective:

To assess the prevalence and clinical features of individuals affected by spinocerebellar ataxia 36 (SCA36) at a large tertiary referral center in the United States.

Methods:

A total of 577 patients with undiagnosed sporadic or familial cerebellar ataxia comprehensively evaluated at a tertiary referral ataxia center were molecularly evaluated for SCA36. Repeat primed PCR and fragment analysis were used to screen for the presence of a repeat expansion in the NOP56 gene.

Results:

Fragment analysis of triplet repeat primed PCR products identified a GGCCTG hexanucleotide repeat expansion in intron 1 of NOP56 in 4 index cases. These 4 SCA36-positive families comprised 2 distinct ethnic groups: white (European) (2) and Asian (Japanese [1] and Vietnamese [1]). Individuals affected by SCA36 exhibited typical clinical features with gait ataxia and age at onset ranging between 35 and 50 years. Patients also suffered from ataxic or spastic limbs, altered reflexes, abnormal ocular movement, and cognitive impairment.

Conclusions:

In a US population, SCA36 was observed to be a rare disorder, accounting for 0.7% (4/577 index cases) of disease in a large undiagnosed ataxia cohort.

Primary lung carcinoid metastatic to the breast

Lung carcinoid tumors account for approximately 2% of lung cancers, with 10% of the tumors represented by the atypical type. While atypical carcinoids are metastatic to intrathoracic lymph nodes in approximately half of the cases on the initial presentation, distant metastases are seen in only 20% of the patients and are found most frequently in bones, liver, adrenal glands, and brain. We present a case of an unusual metastatic disease to the breast in 51-year-old female who developed a new breast mass 2 years after left lower lobectomy due to atypical carcinoid tumor. Atypical pulmonary carcinoid metastases to the breast are exceptionally uncommon, yet they are important considerations for appropriate management, especially with an anamnesis of this neoplasm.

SeqCNV: a novel method for identification of copy number variations in targeted next-generation sequencing data

Background

Targeted next-generation sequencing (NGS) has been widely used as a cost-effective way to identify the genetic basis of human disorders. Copy number variations (CNVs) contribute significantly to human genomic variability, some of which can lead to disease. However, effective detection of CNVs from targeted capture sequencing data remains challenging.

Results

Here we present SeqCNV, a novel CNV calling method designed to use capture NGS data. SeqCNV extracts the read depth information and utilizes the maximum penalized likelihood estimation (MPLE) model to identify the copy number ratio and CNV boundary. We applied SeqCNV to both bacterial artificial clone (BAC) and human patient NGS data to identify CNVs. These CNVs were validated by array comparative genomic hybridization (aCGH).

Conclusions

SeqCNV is able to robustly identify CNVs of different size using capture NGS data. Compared with other CNV-calling methods, SeqCNV shows a significant improvement in both sensitivity and specificity.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-017-1566-3) contains supplementary material, which is available to authorized users.

Practical Approaches for Whole-Genome Sequence Analysis of Heart- and Blood-Related Traits

Whole-genome sequencing (WGS) allows for a comprehensive view of the sequence of the human genome. We present and apply integrated methodologic steps for interrogating WGS data to characterize the genetic architecture of 10 heart- and blood-related traits in a sample of 1,860 African Americans. In order to evaluate the contribution of regulatory and non-protein coding regions of the genome, we conducted aggregate tests of rare variation across the entire genomic landscape using a sliding window, complemented by an annotation-based assessment of the genome using predefined regulatory elements and within the first intron of all genes. These tests were performed treating all variants equally as well as with individual variants weighted by a measure of predicted functional consequence. Significant findings were assessed in 1,705 individuals of European ancestry. After these steps, we identified and replicated components of the genomic landscape significantly associated with heart- and blood-related traits. For two traits, lipoprotein(a) levels and neutrophil count, aggregate tests of low-frequency and rare variation were significantly associated across multiple motifs. For a third trait, cardiac troponin T, investigation of regulatory domains identified a locus on chromosome 9. These practical approaches for WGS analysis led to the identification of informative genomic regions and also showed that defined non-coding regions, such as first introns of genes and regulatory domains, are associated with important risk factor phenotypes. This study illustrates the tractable nature of WGS data and outlines an approach for characterizing the genetic architecture of complex traits.

Corner fracture type spondylometaphyseal dysplasia: Overlap with type II collagenopathies

Spondylometaphyseal dysplasia (SMD) corner fracture type (also known as SMD "Sutcliffe" type, MIM 184255) is a rare skeletal dysplasia that presents with mild to moderate short stature, developmental coxa vara, mild platyspondyly, corner fracture-like lesions, and metaphyseal abnormalities with sparing of the epiphyses. The molecular basis for this disorder has yet to be clarified. We describe two patients with SMD corner fracture type and heterozygous pathogenic variants in COL2A1. These two cases together with a third case of SMD corner fracture type with a heterozygous COL2A1 pathogenic variant previously described suggest that this disorder overlaps with type II collagenopathies. The finding of one of the pathogenic variants in a previously reported case of spondyloepimetaphyseal dysplasia (SEMD) Strudwick type and the significant clinical similarity suggest an overlap between SMD corner fracture and SEMD Strudwick types. © 2016 Wiley Periodicals, Inc.

A hybrid computational strategy to address WGS variant analysis in >5000 samples

Background

The decreasing costs of sequencing are driving the need for cost effective and real time variant calling of whole genome sequencing data. The scale of these projects are far beyond the capacity of typical computing resources available with most research labs. Other infrastructures like the cloud AWS environment and supercomputers also have limitations due to which large scale joint variant calling becomes infeasible, and infrastructure specific variant calling strategies either fail to scale up to large datasets or abandon joint calling strategies.

Results

We present a high throughput framework including multiple variant callers for single nucleotide variant (SNV) calling, which leverages hybrid computing infrastructure consisting of cloud AWS, supercomputers and local high performance computing infrastructures. We present a novel binning approach for large scale joint variant calling and imputation which can scale up to over 10,000 samples while producing SNV callsets with high sensitivity and specificity. As a proof of principle, we present results of analysis on Cohorts for Heart And Aging Research in Genomic Epidemiology (CHARGE) WGS freeze 3 dataset in which joint calling, imputation and phasing of over 5300 whole genome samples was produced in under 6 weeks using four state-of-the-art callers. The callers used were SNPTools, GATK-HaplotypeCaller, GATK-UnifiedGenotyper and GotCloud. We used Amazon AWS, a 4000-core in-house cluster at Baylor College of Medicine, IBM power PC Blue BioU at Rice and Rhea at Oak Ridge National Laboratory (ORNL) for the computation. AWS was used for joint calling of 180 TB of BAM files, and ORNL and Rice supercomputers were used for the imputation and phasing step. All other steps were carried out on the local compute cluster. The entire operation used 5.2 million core hours and only transferred a total of 6 TB of data across the platforms.

Conclusions

Even with increasing sizes of whole genome datasets, ensemble joint calling of SNVs for low coverage data can be accomplished in a scalable, cost effective and fast manner by using heterogeneous computing platforms without compromising on the quality of variants.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-016-1211-6) contains supplementary material, which is available to authorized users.

Short- and Long-term Results of Hybrid Arch and Proximal Descending Thoracic Aortic Repair

Purpose: To evaluate the short- and long-term outcomes of hybrid repair of the arch and proximal descending aorta in a single tertiary center for aortic disease. Methods: A retrospective analysis was performed of 55 patients (median age 67 years; 36 men) who underwent hybrid repair of thoracic aortic pathology with involvement of the arch between January 2005 and May 2015 at a single tertiary center. The pathologies included 40 (73%) with aneurysmal disease, 10 (18%) acute type B aortic dissections, 2 with acute aortic syndrome, an acute type A dissection, and left and aberrant right subclavian artery aneurysms. Seven (13%) procedures were performed as an emergency. Demographics and procedure characteristics were collected for analysis of survival and reinterventions. Results: Complete aortic debranching was performed in 14 (25%) to facilitate endograft placement in zone 0; debranching was partial in 20 (36%) patients for zone 1 deployments and 21 (38%) for zone 2. Primary technical success was achieved in 51 (93%) cases. One patient died in-hospital from aneurysm rupture following aortic debranching prior to stent-graft repair. In another, the stent-graft procedure proved infeasible and was abandoned. The other 2 technical failures were due to type Ia endoleaks. Five (9%) patients died in-hospital (4 of 48 elective and 1 of 7 emergency cases); 2 of these patients died within 30 days (4%). Eight (14%) patients had a stroke, 6 of 48 elective and 2 of the 7 emergency patients. Spinal cord ischemia was reported in 3 (6%) patients. Mean follow-up was 74.6 months. Overall cumulative survival was 70% at 1 year, 68% at 2 years, and 57% at 5 years. Reintervention to the proximal landing zone for type Ia endoleak was required in 6% of cases. The overall rate of aortic reintervention was 18% at 1 year, 21% at 2 years, and 36% at 5 years. Overall extra-anatomic graft patency was 99%. Conclusion: Hybrid repair of the aortic arch and proximal descending thoracic aorta is technically feasible, with acceptable short-term mortality. There is a low rate of proximal landing zone reintervention when hybrid techniques are used to create an adequate proximal landing zone. Extra-anatomic bypass grafts have good long-term patency. Ongoing disease progression means that further distal aortic interventions are often necessary in patients with extensive disease.