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3,812
result(s) for
"molecular variants"
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High-Throughput Sequencing Reveals Apple Virome Diversity and Novel Viruses in the Czech Republic
by
Brožová, Jana
,
Přibylová, Jaroslava
,
Špak, Josef
in
Agricultural practices
,
Algorithms
,
Apple
2025
Apple viruses pose significant threat to global apple production. In this study, HTS technology was used to investigate the apple virome in the Czech Republic. Previously reported viruses, including ACLSV, ASPV, ASGV, ApMV, AGCaV, and CCGaV, were confirmed, and near-complete genomes were assembled. Additionally, two novel viruses, ARWV1 and ARWV2 were identified for the first time in the Czech Republic. Phylogenetic analyses showed low genetic variability among ARWV2 isolates, suggesting a possible recent introduction or limited diversification. In contrast, ARWV1 isolates displayed distinct clustering in the coat protein coding region, separating symptomatic and asymptomatic samples, indicating a potential involvement of genetic determinants in symptom expression. Mixed infections were prevalent, with multiple molecular variants of ACLSV, ASPV, and AGCaV detected within individual samples, along with co-infections involving viruses from different families. Recombination analysis identified frequent recombination events in ACLSV and ASPV, often involving non-apple parental sequences, suggesting their potential for cross-host infections. Additionally, an interspecific recombination event was detected in an almond ApMV isolate, with PNRSV as a minor parent. These findings highlight the impact of agricultural practices on viral evolution and host adaptation. This study demonstrates the utility of HTS as a powerful tool for uncovering viral diversity, recombination events, and evolutionary dynamics.
Journal Article
Pharmacogenomic profile of actionable molecular variants related to drugs commonly used in anesthesia: WES analysis reveals new mutations
by
Angulo-Aguado, Mariana
,
Morel, Adrien
,
Ortega-Recalde, Oscar Javier
in
Alleles
,
allelic frequency
,
Analgesics
2023
Background: Genetic interindividual variability is associated with adverse drug reactions (ADRs) and affects the response to common drugs used in anesthesia. Despite their importance, these variants remain largely underexplored in Latin-American countries. This study describes rare and common variants found in genes related to metabolism of analgesic and anaesthetic drug in the Colombian population. Methods: We conducted a study that included 625 Colombian healthy individuals. We generated a subset of 14 genes implicated in metabolic pathways of common medications used in anesthesia and assessed them by whole-exome sequencing (WES). Variants were filtered using two pipelines: A) novel or rare (minor allele frequency—MAF <1%) variants including missense, loss-of-function (LoF, e.g., frameshift, nonsense), and splice site variants with potential deleterious effect and B) clinically validated variants described in the PharmGKB (categories 1, 2 and 3) and/or ClinVar databases. For rare and novel missense variants, we applied an optimized prediction framework (OPF) to assess the functional impact of pharmacogenetic variants. Allelic, genotypic frequencies and Hardy-Weinberg equilibrium were calculated. We compare our allelic frequencies with these from populations described in the gnomAD database. Results: Our study identified 148 molecular variants potentially related to variability in the therapeutic response to 14 drugs commonly used in anesthesiology. 83.1% of them correspond to rare and novel missense variants classified as pathogenic according to the pharmacogenetic optimized prediction framework, 5.4% were loss-of-function (LoF), 2.7% led to potential splicing alterations and 8.8% were assigned as actionable or informative pharmacogenetic variants. Novel variants were confirmed by Sanger sequencing. Allelic frequency comparison showed that the Colombian population has a unique pharmacogenomic profile for anesthesia drugs with some allele frequencies different from other populations. Conclusion: Our results demonstrated high allelic heterogeneity among the analyzed sampled, enriched by rare (91.2%) variants in pharmacogenes related to common drugs used in anesthesia. The clinical implications of these results highlight the importance of implementation of next-generation sequencing data into pharmacogenomic approaches and personalized medicine.
Journal Article
Analysis of HER2 Expression in Different Histological Subtypes and IHC-Based Molecular Variants of Muscle-Invasive Bladder Carcinoma
2025
Background and Objectives: Urothelial carcinoma of the urinary bladder is a heterogeneous disease with diverse morphological and molecular characteristics. This study aims to analyze the expression of HER2 in 100 consecutive cases of muscle-invasive bladder carcinoma (MIBC), with a special attention to the different histological subtypes and consensus molecular variants determined by IHC methods. Materials and Methods: A retrospective single-center study was conducted on 100 consecutive cases of MIBC (2021–2024). HER2 status is assessed by immunohistochemistry (IHC) (scores 0, 0+, 1+, 2+, 3+), and the results are compared with the published data. Results: We have established that over half of the tumors (~60%) show some level of HER2 expression, with strong expression (3+) present in 25%. There are significant differences among the IHC-based molecular variants: luminal tumors, including papillary tumors, exhibit a frequent HER2 overexpression, whereas those with a basal immunophenotype (e.g., squamous, sarcomatoid variants) are almost entirely HER2-negative. The micropapillary subtype and some other rare subtypes can also express HER2. Conclusions: HER2 is an important biomarker with heterogeneous expression in urothelial carcinoma of the bladder. The present study showed that the frequency and level of HER2 expression vary substantially among different histopathological subtypes and molecular variants. In therapeutic terms, interest in HER2 as a target is growing—new antibody–drug conjugates show a promising activity even in cases with low HER2 expression, which will likely lead to the integration of HER2-directed therapies and routine testing in the future.
Journal Article
Molecular Review of Suspected Alport Syndrome Patients—A Single-Centre Experience
2025
Background: Alport syndrome (AS) is a clinically and genetically heterogeneous glomerulopathy resulting from pathogenic variants in COL4A3, COL4A4, and COL4A5. Genetic diagnosis is increasingly being conducted using next-generation sequencing (NGS). Methods: Within eight years, we examined a group of 247 Polish individuals and found in total 138 unrelated probands suspected with AS based on clinical course, laboratory findings, and/or family history, as well as the total of 109 family members. We applied a targeted NGS panel to identify the genetic spectrum of AS. Known and novel variants were revealed, and detailed evaluation was performed according to ACMG/AMP guidelines to classify them as pathogenic/likely pathogenic/VUS changes. Identified genotypes were compared with clinical manifestations: hematuria, proteinuria, chronic kidney disease, sensorineural hearing impairment, ocular abnormalities, and hypertension. Results: The molecular background was established in 109/138 probands. Overall, 79 different COL4A3-COL4A5 changes (56 known and 23 novel) were revealed. About 97% were SNVs, and only two COL4A5 CNVs were identified. In total, 11 recurrent COL4A3-COL4A5 variants were observed, including the most frequent COL4A5:p.Gly624Asp, accounting for 31% of X-linked AS. Conclusions: The use of NGS panel has shown considerable promise in the field of AS, increasing diagnostic rate to 79% and reducing time to diagnosis. The phenotype-driven gene panel, specific for genetic diseases in the pediatric population, is an affordable alternative to WGS and WES, offering comparable diagnostic efficacy and supporting its implementation as a first-line genetic test in rare diseases, including AS. Based on the obtained genotype–phenotype correlation, we assessed that NGS allows us to avoid invasive renal biopsy in AS diagnosis. It provides AS confirmation/exclusion, atypical AS identification, symptomatic/asymptomatic monoallelic COL4A3-COL4A5 carrier (especially COL4A5 females) determination, and inheritance pattern establishment. AS diagnosis confirmation enables clinical course prediction and is crucial for the early introduction of renoprotective treatment with renin–angiotensin–aldosterone system blockade, aimed at slowing the disease progression and estimating the risk in family members, which is important for genetic counselling.
Journal Article
Prevalence of human papillomavirus types and variants and p16(INK4a) expression in head and neck squamous cells carcinomas in São Paulo, Brazil
2016
Human papillomavirus (HPV) prevalence in head and neck squamous cell carcinomas (HNSCC) diverges geographically. The reliability of using p16(INK4a) expression as a marker of viral infection is controversial in HNSCC. We evaluated HPV types and HPV-16 variants prevalence, and p16(INK4a) expression in HNSCC specimens provided by two different Institutions in São Paulo.
HPV DNA from formalin-fixed specimens was accessed by Inno-LiPA, HPV-16 variants by PCR-sequencing, and p16(INK4a) protein levels by immunohistochemistry.
Overall, HPV DNA was detected among 19.4 % of the specimens (36/186). Viral prevalence was higher in the oral cavity (25.0 %, 23/92) then in other anatomical sites (oropharynx 14,3 %, larynx 13.7 %) when samples from both Institutions were analyzed together. HPV prevalence was also higher in the oral cavity when samples from both Institutions were analyzed separately. HPV-16 was the most prevalent type identified in 69.5 % of the HPV positive smaples and specimens were assigned into Asian-American (57.2 %) or European (42.8 %) phylogenetic branches. High expression of p16(INK4a) was more common among HPV positive tumors.
Our results support a role for HPV-16 in a subset of HNSCC.
Journal Article
Whole-Exome Sequencing Identified Molecular Variants Linked to the Progression of Gastric Precancerous Lesions in Patients from Southwestern Colombia—An Exploratory Approach
by
Zabaleta, Jovanny
,
Mejia-Ortiz, Lizeth
,
Bravo, Luis Eduardo
in
Extracellular matrix
,
Gastric cancer
,
gastric precancerous lesions
2025
Background/Objectives: This study aimed to identify molecular variants associated with the progression of gastric precancerous lesions in a follow-up study conducted on patients from Southwestern Colombia. Methods: Whole-exome sequencing (WES) was performed on patients enrolled in the Colombian chemoprevention trial, who were classified into two groups—progression and regression—based on changes in the severity of their gastric precancerous lesions over 16 years of follow-up. The bioinformatics pipeline included steps for quality control, mapping, variant calling, filtering, and annotation. Associations between molecular variants and lesion progression were analyzed using Fisher’s exact test and the Cochran–Armitage trend test. Additionally, functional impact and pathway enrichment analyses were performed for variants that showed significant associations. Results: Thirty-eight molecular variants from thirty-seven participants were associated with the progression of gastric precancerous lesions. These variants were found in tumor suppressor genes like CDKN2A and CDK4, which are involved in cell cycle regulation and apoptosis. Additionally, variants were identified in extracellular matrix regulators such as COL23A1, LAMA2, and TNR. Other noteworthy findings included variants in FLT1, which is linked to VEGF signaling in angiogenesis, and APOB, which is involved in modulating inflammatory responses. Furthermore, alterations in genes associated with the hemostatic system, such as FGA and F5, underscored the connection between hemostasis and carcinogenesis. Conclusions: This exploratory analysis highlighted some molecular variants that may affect the function, structure, and expression of key proteins involved in cancer development, contributing to the progression of gastric precancerous lesions.
Journal Article
Immunohistochemistry-Based Molecular Profiling of Muscle-Invasive Bladder Cancer: Analysis of 100 Consecutive Cases with Morphological Correlation
2025
Background/Objectives: This study aimed to profile the molecular variants of muscle-invasive bladder cancer (MIBC) based on immunohistochemical analysis and to make a correlation with morphological characteristics in a series of 100 consecutive patients. Methods: A retrospective single-center study was conducted on 100 consecutive cases of MIBC (2021–2024). A selected immunohistochemical (IHC) panel (including CK5/6, CK20, and p16) was applied in all cases to classify the tumors into known molecular variants (luminal papillary, luminal non-specified, luminal unstable, stroma-rich, basal/squamous, neuroendocrine-like). Results: Seven molecular subtypes are identified: basal (33%), luminal papillary (24%), luminal unstable (16%), luminal non-specified (10%), basoluminal (double-positive) (9%), neuroendocrine-like (double-negative with neuroendocrine morphology) (6%), and stroma-rich (2%). This distribution largely matches published data (Consensus Classification and The Cancer Genome Atlas (TCGA)), with minor differences (e.g., a lower share of the stroma-rich variant). A strong correlation is found between the histological subtypes of some tumors and their molecular variant (χ2, p < 0.001): for example, all cases of urothelial carcinoma with squamous differentiation are basal, micropapillary tumors are entirely luminal, and small-cell carcinomas are neuroendocrine-like. Conclusions: The results demonstrate that the morphological subtype of urothelial carcinoma largely predetermines the molecular profile. Combining classic histopathology with IHC-based profiling allows for a more complete characterization of the tumor and aids prognosis and personalized treatment in MIBC.
Journal Article
Real-time RT-PCR high-resolution melting curve analysis and multiplex RT-PCR to detect and differentiate grapevine leafroll-associated associated virus 3 variant groups I, II, III and VI
2012
Doc number: 219 Abstract Background: Grapevine leafroll-associated virus 3 (GLRaV-3) is the main contributing agent of leafroll disease worldwide. Four of the six GLRaV-3 variant groups known have been found in South Africa, but their individual contribution to leafroll disease is unknown. In order to study the pathogenesis of leafroll disease, a sensitive and accurate diagnostic assay is required that can detect different variant groups of GLRaV-3. Methods: In this study, a one-step real-time RT-PCR, followed by high-resolution melting (HRM) curve analysis for the simultaneous detection and identification of GLRaV-3 variants of groups I, II, III and VI, was developed. A melting point confidence interval for each variant group was calculated to include at least 90% of all melting points observed. A multiplex RT-PCR protocol was developed to these four variant groups in order to assess the efficacy of the real-time RT-PCR HRM assay. Results: A universal primer set for GLRaV-3 targeting the heat shock protein 70 homologue (Hsp70h) gene of GLRaV-3 was designed that is able to detect GLRaV-3 variant groups I, II, III and VI and differentiate between them with high-resolution melting curve analysis. The real-time RT-PCR HRM and the multiplex RT-PCR were optimized using 121 GLRaV-3 positive samples. Due to a considerable variation in melting profile observed within each GLRaV-3 group, a confidence interval of above 90% was calculated for each variant group, based on the range and distribution of melting points. The intervals of groups I and II could not be distinguished and a 95% joint confidence interval was calculated for simultaneous detection of group I and II variants. An additional primer pair targeting GLRaV-3 ORF1a was developed that can be used in a subsequent real-time RT-PCR HRM to differentiate between variants of groups I and II. Additionally, the multiplex RT-PCR successfully validated 94.64% of the infections detected with the real-time RT-PCR HRM. Conclusion: The real-time RT-PCR HRM provides a sensitive, automated and rapid tool to detect and differentiate different variant groups in order to study the epidemiology of leafroll disease.
Journal Article
E6/E7 Functional Differences among Two Natural Human Papillomavirus 18 Variants in Human Keratinocytes
by
Villa, Luisa Lina
,
Ferreira, Silvaneide
,
Lino, Vanesca de Souza
in
actinomycin D
,
adenocarcinoma
,
Apoptosis
2021
It is suggested that HPV-18 variants from the A lineage have higher oncogenic potential compared to B variants. Some studies show uneven distribution of HPV-18 variants in cervical adenocarcinomas and squamous cell carcinomas. Regarding HPV-18 variants’ functions, the few studies reported focus on E6, and none were performed using natural host cells. Here, we immortalized primary human keratinocytes (PHKs) with E6/E7 of HPV-18 A1 and B1 sublineages and functionally characterized these cells. PHK18A1 reached immortalization significantly faster than PHK18B1 and formed a higher number of colonies in monolayer and 3D cultures. Moreover, PHK18A1 showed greater invasion ability and higher resistance to apoptosis induced by actinomycin-D. Nevertheless, no differences were observed regarding morphology, proliferation after immortalization, migration, or epithelial development in raft cultures. Noteworthy, our study highlights qualitative differences among HPV-18 A1 and B1 immortalized PHKs: in contrast to PHK18A1, which formed more compact colonies and spheroids of firmly grouped cells and tended to invade and migrate as clustered cells, morphologically, PHK18B1 colonies and spheroids were looser, and migration and invasion of single cells were observed. Although these observations may be relevant for the association of these variants with cervical cancer of different histological subtypes, further studies are warranted to elucidate the mechanisms behind these findings.
Journal Article
Distribution and Genetic Diversity of Grapevine Viruses in Russia
by
Yurchenko, Eugeniya
,
Volodin, Vitalii
,
Vinogradova, Svetlana
in
Berries
,
Coat protein
,
coat proteins
2021
Viral diseases can seriously damage the vineyard productivity and the quality of grape and wine products. Therefore, the study of the species composition and range of grapevine viruses is important for the development and implementation of strategies and tactics to limit their spread and increase the economic benefits of viticulture. In 2014–2019, we carried out a large-scale phytosanitary monitoring of Russian commercial vineyards in the Krasnodar region, Stavropol region and Republic of Crimea. A total of 1857 samples were collected and tested for the presence of Grapevine rupestris stem pitting-associated virus (GRSPaV), Grapevine virus A (GVA), Grapevine leafroll-associated virus-1 (GLRaV-1), Grapevine leafroll-associated virus-2 (GLRaV-2), Grapevine leafroll-associated virus-3 (GLRaV-3), Grapevine fanleaf virus (GFLV), and Grapevine fleck virus (GFkV) using RT-PCR. Out of all samples tested, 54.5% were positive for at least one of the viruses (GRSPaV, GVA, GLRaV-1, GLRaV-2, GLRaV-3, GFLV, GFkV) in the Stavropol region, 49.8% in the Krasnodar region and 49.5% in the Republic of Crimea. Some plants were found to be infected with several viruses simultaneously. In the Republic of Crimea, for instance, a number of plants were infected with five viruses. In the Krasnodar region and the Republic of Crimea, 4.7% and 3.3% of the samples were predominantly infected with both GFkV and GRSPaV, whereas in the Stavropol region, 6% of the selected samples had both GLRaV-1 and GVA infections. We carried out a phylogenetic analysis of the coat protein genes of the detected viruses and identified the presence of GVA of groups I and IV, GRSPaV of groups BS and SG1, GLRaV-1 of group III, GLRaV-2 of groups PN and H4, GLRaV-3 of groups I and III. The results obtained make it possible to assess the viral load and the distribution of the main grapevine viruses on plantations in the viticultural zones of Russia, emphasizing the urgent need to develop and implement long-term strategies for the control of viral diseases of grapes.
Journal Article