Distinction between melanocytic naevi and melanoma occasionally poses a diagnostic challenge in ambiguous cases showing overlapping histological features. Melanomas are characterised by the presence of multiple genomic copy number variants (CNVs), while this is not a feature of naevi. We assessed the feasibility and utility of array-based comparative genomic hybridisation (aCGH) to assess CNVs in melanocytic lesions. DNA was extracted from formalin fixed, paraffin embedded (FFPE) sections of unambiguous naevi (n=19) and melanomas (n=19). The test DNA and gender mismatched human reference DNA were differentially labelled with fluorophores. Equal quantities of the two DNA samples were mixed and co-hybridised to a SurePrint G3 Human CGH 8x60K array, and digitally scanned to capture and quantify the relative fluorescence intensities. The ratio of the fluorescence intensities was analysed by Cytogenomics software (Agilent). Frequent large CNVs were identified in 94.7% of melanoma samples, including losses of 9p (73.6%), 9q (52.6%), 10q (36.8%), 11q (36.8%), 3p (21%), and 10p (21%), and gains of 6p (42.1%), 7p (42.1%), 1q (36.8%), 8q (31.5%) and 20q (21%). Only one naevus showed two large copy number changes. Overall aCGH showed a specificity and sensitivity of 94.7% in separating naevi from melanomas. Based on our results, aCGH can be successfully used to analyse CNVs of melanocytic lesions utilising FFPE derived biopsy samples, providing a potentially useful adjunctive test for the classification of diagnostically challenging melanocytic proliferations.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.pathol.2016.11.008 | DOI Listing |
PLoS Genet
January 2025
Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada.
The synaptonemal complex (SC) is a protein-rich structure essential for meiotic recombination and faithful chromosome segregation. Acting like a zipper to paired homologous chromosomes during early prophase I, the complex is a symmetrical structure where central elements are connected on two sides by the transverse filaments to the chromatin-anchoring lateral elements. Despite being found in most major eukaryotic taxa implying a deeply conserved evolutionary origin, several components of the complex exhibit unusually high rates of sequence turnover.
View Article and Find Full Text PDFPLoS Genet
January 2025
Université Paris-Saclay, INRAE, AgroParisTech, Institute Jean-Pierre Bourgin for Plant Sciences (IJPB), Versailles, France.
Gamete killers are genetic loci that distort segregation in the progeny of hybrids because the killer allele promotes the elimination of the gametes that carry the sensitive allele. They are widely distributed in eukaryotes and are important for understanding genome evolution and speciation. We had previously identified a pollen killer in hybrids between two distant natural accessions of Arabidopsis thaliana.
View Article and Find Full Text PDFCancer Med
January 2025
Department of Neurosurgery, Center for Malignant Brain Tumors, National Glioma MDT Alliance, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Background: The 2021 WHO Classification of Central Nervous System Tumors introduces more molecular markers for glioma reclassification, including TERT promoter (TERTp) mutation as a key feature in glioblastoma diagnosis.
Aims: Given the changes in the entities included in each subtype under the new classification, this research investigated the distribution, prognostic value, and correlations with other molecular alterations of TERTp mutation in different subgroups under this latest classification.
Methods: All glioma patients admitted to Peking Union Medical College Hospital for surgical resection or biopsy from 2011 to 2022 were included.
Recent single-cell experiments that measure copy numbers of over 40 proteins in individual cells at different time points [time-stamped snapshot (TSS) data] exhibit cell-to-cell variability. Because the same cells cannot be tracked over time, TSS data provide key information about the time-evolution of protein abundances that could yield mechanisms that underlie signaling kinetics. We recently developed a generalized method of moments (GMM) based approach that estimates parameters of mechanistic models using TSS data.
View Article and Find Full Text PDFChanges in the copy number of large genomic regions, termed copy number variations (CNVs), contribute to important phenotypes in many organisms. CNVs are readily identified using conventional approaches when present in a large fraction of the cell population. However, CNVs that are present in only a few genomes across a population are often overlooked but important; if beneficial under specific conditions, a de novo CNV that arises in a single genome can expand during selection to create a larger population of cells with novel characteristics.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!