Journal of Molecular Diagnostics最新文献

Myelofibrosis (MF) is a hematologic malignancy with a highly heterogeneous clinical course. Copy-neutral loss of heterozygosity (CN-LOH) may contribute to disease progression by promoting mutation homozygosity. Although single-nucleotide polymorphism (SNP) arrays are the gold standard for CN-LOH detection, optical genome mapping (OGM) has emerged as a promising alternative. In this multicenter study, the capability of OGM to detect CN-LOH in 78 patients with MF was assessed. OGM data were analyzed using both de novo (DN) and guided assembly pipelines (GA), followed by re-analysis of CN-LOH-positive cases with the Variant Intelligence Applications (VIA) software. Results were validated with SNP arrays. Compared with 45% for GA and 37% for DN, VIA demonstrated the highest concordance, confirming 90% (46/51) of CN-LOH events found by SNP arrays. Although VIA maintained a high concordance (90%) for all event sizes, GA (70%) and DN (61%) showed improved concordance for larger events (≥25 Mb). VIA also identified six CN-LOH events in 9p involving the JAK2 gene that were missed by DN and GA. Among 19 CN-LOH events detected by all three pipelines, 89% were confirmed by SNP arrays. Events ≥25 Mb exhibited greater concordance across platforms. These findings demonstrate that OGM, particularly when analyzed with VIA, is a sensitive and reliable method for CN-LOH detection in MF. However, in the absence of broader validation, confirmation with orthogonal methods remains necessary.

Cytomegalovirus, Epstein-Barr virus, BK virus, and adenovirus cause significant morbidity and mortality in immunocompromised individuals, especially those undergoing solid organ and hematopoietic stem cell transplant. Quantitative viral load testing is essential to the monitoring and treatment of disease associated with these viruses in the post-transplant period. In this review, the current guidelines for viral load monitoring are described, highlighting the differences in testing recommendations by virus and transplant type. The state of commercially available, Food and Drug Administration-cleared quantitative viral load assays are also reviewed and the ongoing challenges associated with quantitative viral load testing in the clinical laboratory are described.

In November 2023, our Canadian tertiary care facility implemented optical genome mapping (OGM) as a first-line diagnostic test for adults with newly diagnosed acute leukemias. Here, the analytical performance and clinical utility of OGM alongside karyotype, fluorescence in situ hybridization (FISH), and next-generation sequencing are reported. During test validation, OGM demonstrated robust analytical performance, reproducibility, and limits of detection, revealing 100% specificity, 96.1% sensitivity, and 98.0% accuracy. After implementation, clinical reports from the entire cytogenetic and molecular genetic workflow were prospectively compiled from the first 200 cases to evaluate concordance with parallel karyotype/FISH and added yield of OGM. A total of 640 reportable variants were detected by OGM and stratified on the basis of clinical significance, classified as tier 1A (25%), tier 1B (3%), tier 2 (2%), or tier 3A (70%). Of these, 64 variants were missed by karyotype and FISH, 3 KMT2A partial tandem duplications were missed by next-generation sequencing, and 9 cases with failed karyotype were rescued by OGM: overall impacting 35 cases (18%) by altering diagnostic classification (n = 12) and/or risk stratification (n = 31). Despite comprehensive pre-existing diagnostic workflows, implementation of OGM has revealed diagnostically and prognostically significant alterations in cases otherwise cryptic or failed by karyotype, demonstrating strong clinical utility and supporting its use as a first-tier diagnostic test for hematolymphoid malignancies.