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High-Sensitivity ctDNA Analysis Uncovers Relevant Signals Missed by NGS in Pancreatic Cancer.

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) carries high mortality despite multimodal therapy, and improved biomarkers are needed to guide perioperative care. This study evaluated the prognostic significance of Kirsten rat sarcoma virus (KRAS)-mutant circulating tumor DNA (ctDNA) detected by next-generation sequencing (NGS) and digital droplet PCR (ddPCR) in localized PDAC. EXPERIMENTAL DESIGN: In this prospective cohort study (2020-2024), patients with localized PDAC undergoing neoadjuvant chemotherapy (NAC) were enrolled across multiple sites within Northwestern Medicine. Blood samples for ctDNA were assessed at diagnosis, after NAC, and after resection using tumor-agnostic NGS and ddPCR targeting KRAS G12D/V/R mutations. Overall survival (OS) was assessed using Kaplan-Meier analysis. RESULTS: The cohort included 106 patients. At diagnosis, KRAS ctDNA was detected in 17.2% (17/99) by NGS and 64.9% (63/97) by ddPCR. Detection by both platforms was associated with shorter OS, with the higher-sensitivity ddPCR assay providing greater prognostic discrimination by identifying additional patients with poor outcomes not captured by NGS (NGS median OS 11.2 vs. 30.5 months, P < 0.001; ddPCR median OS 24.7 vs. 70.9 months, P = 0.004). Stratified by detection method, median OS was shortest in patients with ctDNA detected by both NGS and ddPCR (10.9 months), longest in those not detected by either platform (40.7 months), and intermediate in patients detected only by ddPCR (26.9 months; P < 0.001). CONCLUSIONS: In localized PDAC, KRAS-mutant ctDNA detected by NGS or ddPCR was associated with worse survival. ddPCR identified additional patients missed by NGS. Integrating ddPCR with NGS ctDNA measures may improve perioperative risk stratification, although validation is needed before clinical implementation.

Humans

Clinical impact of 16S rRNA RC-PCR NGS on infectious disease management.

16S rRNA metagenomics provides a culture-independent method for diagnosing infections with fastidious or uncultivable organisms, guiding targeted therapy, and detecting polymicrobial communities. This study utilizes reverse complement (RC)-PCR next-generation sequencing (NGS) to accurately identify bacterial pathogens from clinical specimens and assess its impact on clinical decision-making, setting it apart from conventional 16S sequencing approaches. A retrospective analysis of an ISO 15189 accredited 16S RC-PCR NGS diagnostic workflow targeting the V1-6 and V9 regions of the 16S rRNA gene was conducted over a 2-year period, including 390 clinical specimens from 316 patients. 16S RC-PCR NGS results were discussed in a multidisciplinary consultation and subsequently reported to the clinic. In total, 1,283 RC-PCR results were analyzed, of which 517 were from clinical specimens, 284 were negative controls, 66 were positive controls, and 416 were from wet lab and bioinformatic pipeline validation. 16S RC-PCR NGS assay detected bacterial taxa in 179/390 (45.9%) of clinical specimens, while 201/390 (51.5%) were negative, and 10/390 (2.6%) yielded uninterpretable results. The specimen types pus, pleural fluid, and heart valves exhibited the highest positivity rate (68% to 70%). Overall, 16S RC-PCR NGS influenced diagnostic decision making in 145/282 (51.4%) clinical cases and guided therapeutic management in 77/282 (27.3%) cases. Results providing definite evidence for either the presence or absence of bacterial infection were considered clinically valuable. Integration of 16S RC-PCR NGS pathogen detection with multidisciplinary consultation markedly improved clinical management, directly impacting diagnosis and treatment of complex clinical cases in a tertiary care setting. The effect was most pronounced in brain abscess patients, where RC-PCR results guided treatment decisions in 9/13 (69.2%) of cases.IMPORTANCETimely and accurate diagnosis is essential for managing serious infections, yet clinicians often face situations where routine laboratory tests do not provide clear answers. This study demonstrates that next-generation sequencing (NGS) of the bacterial 16S rRNA gene can decisively resolve these uncertainties. By revealing whether bacteria are present in clinical specimens, this approach influenced clinical reasoning and supported treatment decisions across a variety of challenging cases. 16S reverse-complement PCR was especially powerful for brain abscesses and infections where the causative microorganism was unclear, providing clarity that directly improved patient care. These findings show that integrating advanced sequencing with expert clinical interpretation can enhance the management of complex infections and support more confident, evidence-based therapy.

Humans

[State Changes and Stability Grading of Driver Genes in Non-small Cell Lung Cancer Based on Repeated NGS Testing].

BACKGROUND: Next-generation sequencing (NGS)-based driver gene testing has become a routine component of molecular subtyping and precision therapy for non-small cell lung cancer (NSCLC). Dynamic genomic monitoring facilitates early detection of resistance-related molecular alterations and informs timely therapeutic adjustments. However, standardized criteria for evaluating the stability of serial NGS testing are currently lacking, and the applicability of NGS using formalin-fixed paraffin-embedded (FFPE) specimens for dynamic monitoring remains poorly defined. This study aims to establish a stability grading system for driver gene status alterations based on repeated NGS testing, and to provide evidence-based support for clinical repeat biopsy strategies. METHODS: Data from 1232 patients with NSCLC who underwent two or more NGS tests on FFPE tissue specimens at Beijing Chest Hospital between June 2019 and April 2026 were collected retrospectively. Patients with an interval of &#x2265;4 months between the initial and last tests were included to ensure the representativeness of temporal analysis, resulting in a main analysis cohort of 942 patients. The Kappa consistency test was used to evaluate the state stability of nine core driver genes [epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), anaplastic lymphoma kinase (ALK), ROS proto-oncogene 1, receptor tyrosine kinase (ROS1), mesenchymal&#x2011;epithelial transition factor (MET), rearranged during transfection (RET), v-raf murine sarcoma viral oncogene homolog B1 (BRAF), erb&#x2011;b2 receptor tyrosine kinase 2 (ERBB2), and phosphatidylinositol&#x2011;4,5&#x2011;bisphosphate 3&#x2011;kinase catalytic subunit alpha (PIK3CA)] and to construct a five&#x2011;level grading system. Paired variant allele frequency (VAF) differences were compared using the Wilcoxon signed&#x2011;rank test. Independent influencing factors for mutation accumulation were identified by binary Logistic regression. RESULTS: The state stability of the nine genes was classified into five levels: EGFR showed high stability (Kappa=0.838), ROS1/ALK/KRAS good stability, BRAF/PIK3CA/RET moderate stability, and ERBB2 low stability, and MET showed high instability. MET exhibited the highest rate of state change (9.3%) with a raw observed agreement of 90.7%. Its Kappa value (0.172) was influenced by the low prevalence (3.7%) compression effect and should therefore be interpreted alongside the observed agreement (90.7%) and the prevalence-adjusted and bias-adjusted Kappa (PABAK). The VAF of PIK3CA increased significantly (P=0.005). T790M positivity increased from 5.8% to 10.8%, and 30 new C797S mutations were detected at the last test (13 with T790M, 17 without). The overall rate of new driver gene variants in the main cohort was 18.0%. Binary Logistic regression showed that a lower number of initial mutated genes was the only independent predictor of new variants [odds ratio (OR)=0.399, P<0.001], while sex and detection interval showed no independent association. CONCLUSIONS: A five level stability grading system for state changes of driver genes in NSCLC based on repeated NGS testing has been established. MET showed the most frequent state changes, which should be interpreted in conjunction with the prevalence effect. The VAF increase of PIK3CA is an observational finding, and its clinical significance requires further prospective validation. A lower initial mutation burden may reflect tumor clonal complexity and was associated with a higher likelihood of subsequent acquisition of new variants. FFPE based NGS is applicable for repeated testing at clinical treatment decision nodes.

Humans

An open-source clinical bioinformatics pipeline for real-world NGS implementation: translating genomic variants into actionable treatment strategies in oncology.

BACKGROUND: Next-Generation Sequencing (NGS) has become a cornerstone technology in clinical practice, yet its adoption presents significant challenges. Physicians and oncologists must manage vast amounts of genome-scale data and transform it into actionable insights for complex decision-making. While commercial systems exist to synthesize data from NGS experiments into clinical reports, many are hindered by limitations such as closed-source designs that restrict transparency and customization. Additionally, some fail to leverage publicly available genomic databases, missing opportunities to integrate valuable external data. Furthermore, the rigidity of many tools in accommodating diverse NGS panels limits their applicability across varied clinical scenarios. METHODS: To address these limitations, we developed OncoReport, an open-source tool that generates comprehensive reports from NGS analyses. By integrating publicly accessible databases, OncoReport provides a robust, user-friendly environment equipped with essential tools for NGS analysis. This design aims to enhance data interpretation and support informed clinical decision-making. RESULTS: Rigorous testing has demonstrated OncoReport&#x2019;s effectiveness in producing detailed, actionable reports that are clear and easy to use. By automating key aspects of the workflow, the tool significantly reduces manual effort and expedites the synthesis and interpretation of NGS results, making genomic insights more accessible to clinicians. CONCLUSION: OncoReport offers a transparent, flexible, and efficient framework for clinicians to analyze and apply genomic data in patient care. By streamlining workflows and leveraging open-source principles, it empowers healthcare professionals to make informed, data-driven decisions. OncoReport is freely available at https://oncoreport.atlas.dmi.unict.it, with source code and issue tracking on GitHub: https://github.com/knowmics-lab/oncoreport .

Humans

Multivariate Effects of SNPs on Environmental Streptococcal Mastitis Evaluated With an NGS-Based Association Study Using Targeted Resequencing in the Bovine MHC Region.

Mastitis is an inflammatory reaction caused by bacterial infection of the teat, and a relationship between its onset and cattle major histocompatibility complex (BoLA) region has been reported. However, no comprehensive genetic analysis of mastitis caused by environmental streptococci has been reported. Here, we resequenced the BoLA region using a hybridisation capture target next-generation sequencing (NGS) method to identify disease susceptibility markers mapped to the BoLA region in environmental streptococcal mastitis. This study examined 75 cows with mastitis caused by environmental streptococci selected from 1641 cows with mastitis and 222 healthy cows without mastitis in Japan. Targeted sequences obtained from MiSeq NGS were aligned to the bovine reference genome (ARS-UCD1.2/bosTau9), and 2,920,355 variants were detected within the BoLA region of the 297 Holstein cattle. In an association study using 2264 variants after quality control, the top 20 variants with the lowest P values were selected and assigned to the 18 surrounding candidate genes, and a gene network analysis of these genes resulted in the narrowing down of five candidate genes POU5F1, IER3, GNL1, ABCF1, and PRR3. Multivariate effect analysis of all 6 SNPs associated with these 5 genes revealed that they were significantly correlated with mastitis, indicating that they were useful for classification of mastitis-resistant and mastitis-susceptible cattle. This is the first report to identify SNPs associated with environmental streptococcal mastitis with an NGS-based association study using targeted resequencing in the BoLA region, and understanding host factors may provide important clues for mastitis control.

Animals

Diagnostic and Monitoring Strategies for VEXAS Syndrome: Evaluating Sanger Sequencing, NGS, and the SWIM-Score.

VEXAS syndrome is an adult-onset autoinflammatory disorder caused by somatic UBA1 variants, but there are no standardized criteria for genetic testing or diagnostics. This study compared Sanger sequencing and next-generation sequencing (NGS) for detecting UBA1 variants in patients with suspected VEXAS, assessed the ability of Sanger sequencing to estimate variant allele fractions (VAFs), and evaluated the Maeda et al. scoring system for selecting patients for genetic testing in a primary cohort and a validation cohort. In the primary cohort of 104 patients, Sanger sequencing identified VEXAS variants in 12%, with no additional cases detected by NGS. Sanger sequencing accurately quantified VAFs ranging from 0.1 to 0.9. In a small longitudinal subset (n&#x2009;=&#x2009;3), VAFs in blood correlated with CRP levels, increased over time despite various treatments, but decreased in two patients after initiation of Azacitidine treatment. The novel parameters, VAF in myeloid cells and VEXAS cell concentration, showed promise as exploratory markers for patient monitoring. The Maeda-score, requiring a threshold score of 2 for 100% sensitivity, exhibited low specificity-29% in the primary cohort and 41% in the validation cohort (n&#x2009;=&#x2009;62, with 2 carrying VEXAS variants). In contrast, the simplified SWIM-score-based on Skin involvement, Weight loss, Inflammation, and Macrocytic anemia-achieved 100% sensitivity in both cohorts, with higher specificities of 47% and 65%, respectively. In conclusion, Sanger sequencing reliably detected UBA1 variants and quantified VAFs. Monitoring VAF and VEXAS cell concentration may track disease progression, and the SWIM-score demonstrated potential for accurately selecting patients for UBA1 testing.

Humans

Systematic performance evaluation and application validation of an end-to-end NGS workstation.

Next-generation sequencing (NGS) library preparation is a core component of precision genomics, but it is commonly constrained by inefficiency, variability, and low throughput of manual protocols. To address these limitations, we developed and systematically evaluated a fully automated NGS workstations and further validated its performance across representative application scenarios. The automated system reduced total processing time from 8 to 10 to 4&#x2013;6&#xa0;h. At the same time, it maintained similar performance in pre-library metric, including DNA yield and fragment size, as well as post-capture sequencing metrics (Q30&#x2009;>&#x2009;90%, mapping rates&#x2009;>&#x2009;95%, on-target rates 85&#x2013;90%). The duplication rate was reduced to 5&#x2013;8%, compared with 10&#x2013;15% for manual methods, indicating increased library complexity. Bioinformatic evaluation of inter-species read mapping showed minimal cross-contamination, with a maximum contamination ratio of 0.0003%, indicating effective sample isolation in the automated workflow. High concordance in variant detection was observed between automated and manual workflows. Overall, this automated workstation provides a standardized and reproducible workflow that supports scalable precision genomics applications.

High-Throughput Nucleotide Sequencing

Trastuzumab Deruxtecan in Metastatic Urothelial Carcinoma with NGS-Detected ERBB2 Amplification: A Four-Patient Real-World Case Series.

Background: Next-generation sequencing (NGS)-detected ERBB2 amplification occurs in a subset of urothelial carcinomas, but its role as a treatment-selection marker for trastuzumab deruxtecan (T-DXd) remains uncertain. Methods: We retrospectively reviewed four patients with metastatic urothelial carcinoma treated with T-DXd in routine practice from 2024. Treatment selection was based on NGS-detected ERBB2 amplification because HER2 immunohistochemistry and in situ hybridization were unavailable. Results: Four men aged 65-76 years received T-DXd: one in the second line and three in the fourth or fifth line. The best radiological responses, abstracted from contemporaneous radiology reports and oncology medical records, were complete response in one patient, partial response in one, and stable disease in two. Three patients had previously received enfortumab vedotin. Documented adverse events included fatigue, anemia, diarrhea, rash, and leukopenia. No interstitial lung disease or pneumonitis was documented in the available records. Conclusions: These observations are descriptive and hypothesis-generating. They do not establish the efficacy or safety of T-DXd or validate ERBB2 amplification as a predictive biomarker, but they support prospective evaluation of genomic ERBB2 amplification when standard HER2 testing is unavailable.

Humans

Analytical and clinical performance validation of HPV-SEQ, a novel NGS-based liquid biopsy platform for detection and quantification of human papilloma virus circulating tumor DNA.

BACKGROUND: Human papillomavirus (HPV) is the primary causative driver of oropharyngeal squamous cell carcinoma (OPSCC). Accurate detection of HPV-DNA is critical for risk stratification and management of OPSCC. However, assays designed to detect HPV in primary tumors do not allow monitoring of HPV-DNA over time, whereas commercially available droplet digital PCR-based methods for assessment of circulating cell free (cf)HPV-DNA in plasma remain suboptimal, hindering adaptation into clinical practice. We have developed HPV-SEQ, a novel next-generation-sequencing (NGS) based method for detection and quantification of HPV16/18 DNA in plasma of patients with OPSCC. METHODS: The assay uses primers targeting the L1 gene of HPV16 and HPV18 viral genomes and strain specific calibrators at a defined concentration to determine the ratio of native HPV to a known standard, enabling accurate reporting of patient-derived HPV16/18 viral load in a sample. This study was conducted using two different patient populations in addition to healthy donors and contrived material. All experiments were performed to fulfill several applicable analytical, performance and validation guidelines. RESULTS: A thorough analytical characterization and clinical validation of this platform demonstrates that HPV-SEQ detects cfHPV-DNA with exceptional limit of quantification and high precision, providing a foundation for integrating this platform into clinical settings. CONCLUSIONS: This ultra-sensitive HPV profiling method with optimal analytical performance may represent a significant advancement in risk stratification, treatment management, and post-treatment surveillance for patients with OPSCC.

Humans

Day&#x2009;+&#x2009;30 detection of minimal residual FLT3-ITD by high-sensitivity PCR-NGS predicts relapse risk and guides post-transplant maintenance in AML.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has improved outcomes in patients with acute myeloid leukemia (AML) harboring FLT3-internal tandem duplication (FLT3-ITD) mutations. However, relapse still occurs in 15-35% of these patients after transplantation. Therefore, early and highly sensitive detection methods are required to identify patients at risk of relapse and enable timely post-transplant intervention. METHODS: In this NICHE cohort study, a total of 136 patients were included, then we evaluated whether high-sensitivity polymerase chain reaction (PCR)-next-generation sequencing (NGS) for FLT3-ITD (limit of detection: 5&#x2009;&#xd7;&#x2009;10-6) on day&#x2009;+&#x2009;30 post-HSCT could identify patients at a high risk of relapse and inform decisions regarding maintenance therapy. RESULTS: Among the 136 patients, 37 patients (27.2%) had detectable FLT3-ITD clones on day&#x2009;+&#x2009;30. These patients exhibited a significantly higher cumulative incidence of post-HSCT multiparameter flow cytometry (MFC)-measurable residual disease (MRD) relapse (40.3% vs. 18.8%, p&#x2009;=&#x2009;0.001). Notably, FLT3-ITD-positive patients who received FLT3 inhibitor maintenance therapy had no relapses, while 6 out of the 13 patients who did not receive maintenance therapy relapsed. Conversely, FLT3-ITD-negative patients without high-risk factors (2022 European LeukemiaNet adverse-risk group, relapsed/refractory AML, MFC-MRD positivity pre-HSCT) showed limited benefit from maintenance therapy (MFC-MRD-free survival: hazard ratio (HR)&#x2009;=&#x2009;0.25 (0.03-2.11), p&#x2009;=&#x2009;0.204; OS: HR&#x2009;=&#x2009;0.20 (0.02-1.70), p&#x2009;=&#x2009;0.142). CONCLUSIONS: This is the first study to demonstrate that detection of minimal FLT3-ITD clones at the fixed time point of day&#x2009;+&#x2009;30 post-HSCT can reliably stratify relapse risk in AML patients and provide a rationale for individualized post-transplant maintenance therapy.

Humans

Optimizing GRIDSS for clinical use: A targeted NGS filtering strategy for germline structural variant detection.

Detecting intermediate-sized structural variants (SVs) remains challenging in diagnostics, as tools for single-nucleotide and copy-number variants, particularly read-depth-based methods, are often insufficient. GRIDSS addresses this gap by integrating paired-end mapping, split-read analysis, and assembly-based approaches. However, its use in targeted sequencing and diagnostic workflows remains complex. NGS panel data from 9726 patients with suspected hereditary cancer were analyzed using GRIDSS. A filtering strategy was developed to prioritize clinically relevant germline SVs. Multiple parameter settings were tested to optimize performance. The initial dataset of 1,307,592 variants was reduced to 89 candidates after applying the selected filtering strategy. Of these, 24 had been previously detected by routine callers and were not further analyzed. Among the remaining 65, 13 were considered likely true positives after visual inspection using IGV. Experimental validation was performed by Sanger/Nanopore long-read sequencing for these variants, all of which were confirmed. Eight were classified as (likely) pathogenic, including two frameshift duplications in MSH6, one splicing variant in BARD1, and five mobile element insertions in APC, BRCA2, and PALB2. Altogether, GRIDSS implementation increased diagnostic yield while maintaining feasibility for diagnostic workflows. Comprehensive workflow scheme for germline structural variant detection and results in our diagnostic setting.

Humans

Extraction, Purification, and Next-Generation Sequencing (NGS) Analysis of DNA and RNA from Formalin-Fixed and Paraffin-Embedded (FFPE) Tissue.

Formalin fixed paraffin embedded (FFPE) tissues have long been used for immunohistological analyses. FFPE tissues can be stored at room temperature for several years enabling analyses to be performed later. Ease of storage and transport makes these tissues an attractive source of biological material. However, formalin fixation results in chemical modifications of proteins and nucleic acids that poses a major challenge to any type of analysis. Recovery of nucleic acids for quantitative assays is rendered difficult due to degradation resulting from fixation and long-term storage, producing low usable yields. Extensive efforts in the last 20&#xa0;years have led to significant improvements in use of FFPE tissues for DNA and RNA analyses and resulted in development of sensitive assays for a wide range of applications, including next-generation sequencing. In this chapter, we describe the optimization of methods for sequential extraction of DNA and RNA from FFPE tissue and subsequent preparation of DNA-seq and RNA-seq libraries for use with the Illumina platform using commercially available reagents/kits.

Paraffin Embedding

An Optimized Adaptation of DamID for NGS Applications.

Recent studies have implicated higher-order genome organization in the regulation of genes and cellular state. Lamina-Associated Domains (LADs) are regions of heterochromatin associated with the nuclear envelope and the nuclear lamina, a protein network involved in both nuclear organization and genome structure. LADs are developmentally regulated, and their dysregulation is associated with several diseases and pathological states, including cancer and premature aging. In addition to LADs, other nuclear protein compartments appear to scaffold or support unique chromatin environments to affect gene expression. These revelations carry profound implications for our comprehension of developmental processes and the pathogenesis of various diseases, especially given the numerous disorders already directly associated with, for example, mutations in lamin and INM proteins. This spatial compartmentalization of chromatin subtypes to unique protein compartments has led to the adoption of proximity-labeling methods, such as DamID (DNA Adenine Methyltransferase Identification), to identify these unique chromatin compartments.

Humans

Towards a Robust cell-free DNA Isolation Protocol for NGS Applications in a Clinical Molecular Diagnostics Setting.

Cell-free DNA (cfDNA), released from apoptotic and necrotic cells into body fluids, is a non-invasive source of genetic information for disease prediction, diagnosis, and monitoring. However, its low abundance makes cfDNA highly susceptible to various pre-analytical influences, potentially increasing high molecular weight (HMW) or genomic DNA (gDNA) compromising downstream cfDNA analyses. This study evaluated the impact of different cfDNA-stabilizing blood collection tubes (BCT; Cell-Free DNA BCT, Streck; S-Monovette cfDNA Exact, Sarstedt) stored at room temperature for 1, 5, or 10 days, prior to plasma isolation using different isolation methods (magnetic bead-based or silica column-based) on cfDNA stability and yield. DNA quantity and quality were assessed by fluorometric quantification, automated fragment analysis, and gene-specific quantitative PCR. Streck-based workflows maintained stable cfDNA yields and characteristic mononucleosomal fragmentation profiles across all storage times. In contrast, Sarstedt tubes showed reduced cfDNA concentrations after 5 days and a pronounced increase at 10 Days, accompanied by high-molecular weight DNA patterns consistent with white-blood cells (WBC) lysis. These trends were largely independent of the extraction method. Overall, the results demonstrate that blood collection tube chemistry critically influences cfDNA integrity during delayed processing. Streck tubes, particularly when combined with silica column-based isolation method, provided the most robust and reproducible workflow for routine molecular diagnostics, whereas Sarstedt tubes produced physiologically implausible results after extended storage.

blood collection tubes

UPDhmm: detecting uniparental disomy from NGS trio data.

SUMMARY: Uniparental disomies (UPDs) are copy-neutral chromosomal alterations that occur when both copies of a chromosome pair (entire or segmental) come from one parent. UPDs, including isodisomies (identical parental chromosome) and heterodisomies (two different homologs from the same parent), reflect meiotic and/or mitotic aberrations of chromosomal segregation that can be associated with congenital or acquired disease. Despite their relevance, current methods to detect UPDs using sequence data (exomes or genomes) have limited sensitivity for small events, cannot precisely determine the UPD sub-type or coordinates, and perform poorly when including individuals or populations with consanguinity. We present UPDhmm, a novel tool that uses trio-based sequence data (proband and parents) and models inheritance patterns. UPDhmm predicts the most likely inheritance scenario, normal Mendelian inheritance versus UPD event, based on genotype combinations using a Hidden Markov Model (HMM). We validated the method using simulations on exome and genome data from 1000-Genomes projects. UPDhmm overperformed currently available methods in detecting simulated UPD events in both data types. We applied UPDhmm to a collection of nearly 2400 families with a proband with autism spectrum disorder (Simons Simplex Collection Project) and identified UPD events in two affected individuals, one of them previously unreported. These two events, a paternal isodisomy of chr8 and a maternal heterodisomy of chr22, can be genetic causes of the disease, demonstrating the clinical utility of UPDhmm. Thus, UPDhmm can facilitate the incorporation of UPD detection into clinical pipelines of genomic analysis. AVAILABILITY AND IMPLEMENTATION: UPDhmm is implemented in R and is available in the Bioconductor package (version 1.5.0): https://www.bioconductor.org/packages/release/bioc/html/UPDhmm.html. The source code can be found at https://github.com/martasevilla/UPDhmm under the MIT license.

Uniparental Disomy

Next-Generation Sequencing Completion and Timeliness Using a Reflex Testing Protocol for Patients with Stage II to IV Nonsquamous Non-Small Cell Lung Cancer.

BACKGROUND: Next-generation Sequencing (NGS) is critical for providing treatment recommendations across multiple stages of non-small cell lung cancer (NSCLC). However, a substantial proportion of patients do not undergo testing. This study evaluated the completion rates and timeliness of NGS in patients with stage II to IV NSCLC at a single academic institution with a reflex NGS testing protocol. METHODS: Patients with stage II to IV nonsquamous NSCLC (ns-NSCLC) diagnosed between 2015 and 2022 were identified retrospectively. A reflex, tissue-based testing protocol was initiated in 2015 using in-house NGS. Pyrosequencing was performed if NGS failed. RESULTS: 501 patients were included: 75 (15.0%) with stage II, 82 (16.4%) with stage III, and 344 (68.6%) with stage IV ns-NSCLC. Tissue NGS was completed in 380 (75.8%) patients and 465 (92.8%) completed some tissue-based genomic testing when including pyrosequencing. Median time from biopsy to NGS was 17.0 days (range, 6-61 days). 61.0% of patients had NGS results prior to a first treatment of any type and 88.4% had tissue NGS results prior to systemic therapy. Among stage IV patients with completed NGS, median overall survival was 2.27 years for patients with NGS results prior to first treatment compared to 1.08 years for patients without NGS results prior to treatment initiation (P = .04). CONCLUSIONS: Implementation of an in-house, reflex NGS testing protocol enabled rapid genomic profiling in a high proportion of patients with stage II to IV ns-NSCLC. NGS completion prior to receiving first-line therapy was associated with improved survival compared to completion after first line treatment in stage IV patients.

Humans

The diagnostic potential of combined quantitative polymerase chain reaction and next-generation sequencing using the same primers for periprosthetic joint infection.

Next-generation sequencing (NGS) enables the detection of specific pathogens unidentifiable by conventional cultures, but its application in orthopedics remains inconsistent due to background contamination and irreproducible findings. This study evaluated the diagnostic performance of a novel workflow combining broad-range 16S rRNA gene quantitative PCR (qPCR) screening with downstream NGS, focusing on bacterial biomass thresholds. The qPCR assay demonstrated excellent intrarater reliability, with an intraclass correlation coefficient (ICC) of 0.961 (95% confidence interval, 0.881 to 0.997). Based on serially diluted positive controls, a quantitative threshold of 10&#x2075; CFU/mL was established as the minimum concentration required for the consistent detection of fastidious taxa, such as Escherichia coli. When evaluated against conventional cultures using 95 sonicate fluid and 276 pre/intraoperative tissue samples, the qPCR assay achieved a sensitivity of 80% and a specificity of 72%. Subsequent NGS sequencing of 26 clinical samples and 9 controls showed concordance in 4 of 6 culture-positive infected cases with NGS taxonomy, whereas the remaining discrepancies were likely attributable to culture-based phenotypic misidentification. Notably, among the qPCR-positive cases, three were culture-negative, including two hip prosthesis loosening cases exhibiting polymicrobial profiles, and one post-traumatic osteoarthritis case harboring low-level Staphylococcus. Crucially, this post-traumatic patient developed delayed periprosthetic joint infection (PJI) 2 years post-surgery, with cultures identifying Staphylococcus previously detected by the initial NGS analysis. Integrating qPCR screening with targeted NGS effectively refines pathogen identification, filters environmental artifacts, and overcomes the diagnostic limitations of culture-negative infections in orthopedic practice.IMPORTANCENext-generation sequencing (NGS) enables the detection of specific pathogens in clinical samples that are not identifiable by conventional methods. However, NGS applications in orthopedics have not been quantitatively evaluated, and findings have been inconsistent owing to contaminants and the presence of non-credible causative organisms. These factors primarily stem from the failure to evaluate low-biomass samples and the absence of proper controls, such as negative controls or mock community DNA samples. This study demonstrates that interpreting results from low-biomass samples requires careful consideration because NGS relies on relative bacterial abundances; distinguishing likely pathogens from contaminants is particularly challenging when bacterial loads are low. We demonstrated that combining NGS with quantitative PCR (qPCR) and applying a Cq cutoff can reduce false positives.

Humans