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This paper outlines experimental results on a model system of PCBM and PS for control parameter exploration of PCBM crystallisation. PS layer attributes, and annealing temperature amongst others are the variables explored.

This paper analyses crystal properties of PCBM when annealed in a bilayer with PS on the top. There are intriguing formations and definite thresholds to the varying reproducible morphologies found. This paper suggests that the PS layer greatly influences PCBM crystal nucleation rate and final morphology.

This paper examines beach plastics in a pie chart by proportionality using previous studies that developed characterisation techniques. These techniques include inferring industrial sources of plastic pollution. This paper combines these methods with a comparison of industry patent statistical proportion for geographical origin inference.

Implementation of polygenic risk scores (PRS) may improve disease prevention and management but requires the construction and validation of clinical assays, interpretation, and reporting pipelines. We developed a clinical genotype array-based assay for published PRS for 6 common diseases. First, we calculated PRS for 36,423 Mass General Brigham Biobank (MGBB) participants. Finding significant variation in the PRS distributions by race, we implemented adjustment for population structure with ancestry-informative principal components. We replicated published thresholds for odds ratio (OR)>2 in MGBB overall [ranging from 1.75 (1.57, 1.95) for Type 2 diabetes to 2.38 (2.07, 2.73) for breast cancer]. After confirming the high performance and robustness of the pipeline for use as a clinical assay, we analyzed the first 141 prospective samples from the Genomic Medicine at VA Study; frequency of PRS corresponding to published OR>2 ranged from 5/141 (3.6%) for colorectal cancer to 8/48 (16.7%) for breast cancer. Our development of a clinical PRS assay for multiple conditions illustrates the generalizability of this process and necessary technical and reporting decisions for meaningful clinical PRS implementation.

The advancement of precision medicine requires new methods to coordinate and deliver genetic data from heterogeneous sources to physicians and patients. The eMERGE III Network enrolled >25,000 participants from biobank and prospective cohorts of predominantly healthy individuals for clinical genetic testing to determine clinically actionable findings. The network developed protocols linking together the 11 participant collection sites and 2 clinical genetic testing laboratories. DNA capture panels targeting 109 genes were used for testing of DNA and sample collection, data generation, interpretation, reporting, delivery, and storage were each harmonized. A compliant and secure network enabled ongoing review and reconciliation of clinical interpretations, while maintaining communication and data sharing between clinicians and investigators. A total of 202 individuals had positive diagnostic findings relevant to the indication for testing and 1,294 had additional/secondary findings of medical significance deemed to be returnable, establishing data return rates for other testing endeavors. This study accomplished integration of structured genomic results into multiple electronic health record (EHR) systems, setting the stage for clinical decision support to enable genomic medicine. Further, the established processes enable different sequencing sites to harmonize technical and interpretive aspects of sequencing tests, a critical achievement toward global standardization of genomic testing. The eMERGE protocols and tools are available for widespread dissemination.

Clinical laboratories offering genome sequencing have the opportunity to return pharmacogenomic findings to patients, providing the added benefit of preemptive testing that could help inform medication selection or dosing throughout the lifespan. Implementation of pharmacogenomic reporting must address several challenges, including inherent limitations in short-read genome sequencing methods, gene and variant selection, standardization of genotype and phenotype nomenclature, and choice of guidelines and drugs to report. An automated pipeline, lmPGX, was developed as an end-to-end solution that produces two versions of a pharmacogenomic report, presenting either Clinical Pharmacogenetics Implementation Consortium or US Food and Drug Administration guidelines for 12 genes. The pipeline was validated for performance using reference samples and pharmacogenetic data from the Genetic Testing Reference Materials Coordination Program. To determine performance and limitations, lmPGX was compared with three additional publicly available pharmacogenomic pipelines. The lmPGX pipeline offers clinical laboratories an opportunity for seamless integration of pharmacogenomic results with genome reporting.

Diagnostic next-generation sequencing (NGS)-based gene panels are increasingly used for prevalent disorders with genetic and clinical heterogeneity. Clinical development, validation, and quality management of these panels ideally includes reference samples containing prevalent pathogenic variants; however, clinical domain expertise to select appropriate variants may not be present, samples are often not publicly available, and their inclusion is associated with added cost. Expert-designed, multiplexed controls can remedy some of these challenges. One approach relies on spiking biosynthetic fragments carrying desired variants into human genomic DNA. We piloted the utility of this approach for hypertrophic cardiomyopathy. Data from >3000 previously sequenced probands were used to select 10 common pathogenic and/or technically challenging variants in the top hypertrophic cardiomyopathy genes. Multiplexed controls were constructed across a range of ideal and realistic allelic fractions for heterozygous germline variants. NGS was performed in quadruplicate, and results were compared with diagnostic NGS data for the source patient samples. Overall, results were indistinguishable from patient-derived data with variants being detected at or reasonably close to the targeted allelic fraction ratios. The exception was a common 25-bp deletion in MYBPC3, underscoring the importance of including such variants in test development. These controls may be an attractive addition to the repertoire of materials for development, validation, and quality monitoring of clinical NGS assays.

Variant interpretation depends on accurate annotations using biologically relevant transcripts. We have developed a systematic strategy for designating primary transcripts, and applied it to 109 hearing loss-associated genes that were divided into 3 categories. Category 1 genes (n=38) had a single transcript, Category 2 genes (n=32) had multiple transcripts, but a single transcript was sufficient to represent all exons, and Category 3 genes (n=38) had multiple transcripts with unique exons. Transcripts were curated with respect to gene expression reported in the literature and the Genotype-Tissue Expression Project. In addition, high frequency loss of function variants in the Genome Aggregation Database, and disease-causing variants in ClinVar and the Human Gene Mutation Database across the 109 genes were queried. These data were used to classify exons as "clinically relevant", "uncertain significance", or "clinically insignificant". Interestingly, 7% of all exons, containing >124 "clinically significant" variants, were of “uncertain significance”. Finally, we used exon-level next generation sequencing quality metrics generated at two clinical labs, and identified a total of 43 technically challenging exons in 20 different genes that had inadequate coverage and/or homology issues which might lead to false variant calls. We have demonstrated that transcript analysis plays a critical role in accurate clinical variant interpretation.

Variant interpretation depends on accurate annotations using biologically relevant transcripts. We have developed a systematic strategy for designating primary transcripts and have applied it to 109 hearing loss–associated genes that were divided into three categories. Category 1 genes (n = 38) had a single transcript; category 2 genes (n = 33) had multiple transcripts, but a single transcript was sufficient to represent all exons; and category 3 genes (n = 38) had multiple transcripts with unique exons. Transcripts were curated with respect to gene expression reported in the literature and the Genotype-Tissue Expression Project. In addition, high-frequency loss-of-function variants in the Genome Aggregation Database and disease-causing variants in ClinVar and the Human Gene Mutation Database across the 109 genes were queried. These data were used to classify exons as clinically significant, insignificant, or of uncertain significance. Interestingly, 6% of all exons, containing 124 reportedly disease-causing variants, were of uncertain significance. Finally, we used exon-level next-generation sequencing quality metrics generated at two clinical laboratories and identified a total of 43 technically challenging exons in 20 different genes that had inadequate coverage and/or homology issues that might lead to false-variant calls. We have demonstrated that transcript analysis plays a critical role in accurate clinical variant interpretation.

RASopathies include a group of syndromes caused by pathogenic germline variants in RAS-MAPK pathway genes and typically present with facial dysmorphology, cardiovascular disease, and musculoskeletal anomalies. Recently, variants in RASopathy-associated genes have been reported in individuals with apparently nonsyndromic cardiomyopathy, suggesting that subtle features may be overlooked. To determine the utility and burden of adding RASopathy-associated genes to cardiomyopathy panels, we tested 11 RASopathy-associated genes by next-generation sequencing (NGS), including NGS-based copy number variant assessment, in 1,111 individuals referred for genetic testing for hypertrophic cardiomyopathy (HCM) or dilated cardiomyopathy (DCM). Disease-causing variants were identified in 0.6% (four of 692) of individuals with HCM, including three missense variants in the PTPN11, SOS1, and BRAF genes. Overall, 36 variants of uncertain significance (VUSs) were identified, averaging ∼3VUSs/100 cases. This study demonstrates that adding a subset of the RASopathy-associated genes to cardiomyopathy panels will increase clinical diagnoses without significantly increasing the number of VUSs/case.

Dilated cardiomyopathy is characterized by substantial locus, allelic, and clinical heterogeneity that necessitates testing of many genes across clinically overlapping diseases. Few studies have sequenced sufficient individuals; thus, the contributions of individual genes and the pathogenic variant spectrum are still poorly defined. We analyzed 766 dilated cardiomyopathy patients tested over 5 years in our molecular diagnostics laboratory. Patients were tested using gene panels of increasing size from 5 to 46 genes, including 121 cases tested with a multiple-cardiomyopathy next-generation panel covering 46 genes. All variants were reassessed using our current clinical-grade scoring system to eliminate false-positive disease associations that afflict many older analyses. Up to 37% of dilated cardiomyopathy cases carry a clinically relevant variant in one of 20 genes, titin (TTN) being the largest contributor (up to 14%). Desmoplakin (DSP), an arrhythmogenic right ventricular cardiomyopathy gene, contributed 2.4%, illustrating the utility of multidisease testing. The clinical sensitivity increased from 10 to 37% as gene panel sizes increased. However, the number of inconclusive cases also increased from 4.6 to 51%. Our data illustrate the utility of broad gene panels for genetically and clinically heterogeneous diseases but also highlight challenges as molecular diagnostics moves toward genome-wide testing. Genet Med 16 8, 601–608.

Diagnostic next-generation sequencing (NGS)-based gene panels are increasingly used for prevalent disorders with genetic and clinical heterogeneity. Clinical development, validation, and quality management of these panels ideally includes reference samples containing prevalent pathogenic variants; however, clinical domain expertise to select appropriate variants may not be present, samples are often not publicly available, and their inclusion is associated with added cost. Expert-designed, multiplexed controls can remedy some of these challenges. One approach relies on spiking biosynthetic fragments carrying desired variants into human genomic DNA. We piloted the utility of this approach for hypertrophic cardiomyopathy. Data from3000 previously sequenced probands were used to select 10 common pathogenic and/or technically challenging variants in the top hypertrophic cardiomyopathy genes. Multiplexed controls were constructed across a range of ideal and realistic allelic fractions for heterozygous germline variants. NGS was performed in quadruplicate, and results were compared with diagnostic NGS data for the source patient samples. Overall, results were indistinguishable from patient-derived data with variants being detected at or reasonably close to the targeted allelic fraction ratios. The exception was a common 25-bp deletion in MYBPC3, underscoring the importance of including such variants in test development. These controls may be an attractive addition to the repertoire of materials for development, validation, and quality monitoring of clinical NGS assays.

Purpose: To develop and validate VisCap, a software program targeted to clinical laboratories for inference and visualization of germ-line copy-number variants (CNVs) from targeted next-generation sequencing data. Genet Med 18 7, 712–719. Methods: VisCap calculates the fraction of overall sequence coverage assigned to genomic intervals and computes log2 ratios of these values to the median of reference samples profiled using the same test configuration. Candidate CNVs are called when log2 ratios exceed user-defined thresholds. Genet Med 18 7, 712–719. Results: We optimized VisCap using 14 cases with known CNVs, followed by prospective analysis of 1,104 cases referred for diagnostic DNA sequencing. To verify calls in the prospective cohort, we used droplet digital polymerase chain reaction (PCR) to confirm 10/27 candidate CNVs and 72/72 copy-neutral genomic regions scored by VisCap. We also used a genome-wide bead array to confirm the absence of CNV calls across panels applied to 10 cases. To improve specificity, we instituted a visual scoring system that enabled experienced reviewers to differentiate true-positive from false-positive calls with minimal impact on laboratory workflow. Genet Med 18 7, 712–719. Conclusions: VisCap is a sensitive method for inferring CNVs from targeted sequence data from targeted gene panels. Visual scoring of data underlying CNV calls is a critical step to reduce false-positive calls for follow-up testing. Genet Med 18 7, 712–719.

Retinal vascular changes and the development of plus disease are the hallmarks of retinopathy of prematurity (ROP). The purpose of this study was to evaluate whether or not serial examinations of retrobulbar blood flow characteristics, as measured by color Doppler imaging (CDI) performed repeatedly over a period of several weeks, would be useful for predicting those infants at risk for developing plus disease and to determine whether this technique may be used as an objective tool for confirming the presence of plus disease. Of the 73 infants followed in this study, 14 (19%) developed plus disease confirmed by a panel of experts. When comparing the group of infants developing plus disease with those infants who did not develop plus disease, we did not find any significant differences in the retrobulbar blood flow characteristics of either the central retinal or ophthalmic arteries. Color Doppler imaging did not appear to be a clinically useful tool in the longitudinal management of ROP, nor did it appear to be useful as an objective determinant of plus disease in these premature infants.