Search Results (767)

Dermatophytes are keratinophilic fungi that cause a wide range of superficial infections in humans and animals. The Trichophyton mentagrophytes species complex is one of the most clinically important groups due to its broad host range, widespread distribution, and increasing involvement in antifungal-resistant infections. Here, we described the epidemiology of T. mentagrophytes over a period of 4 years detected in the northeastern part of Italy and provided the genomic characterization of clinical isolates. ITS sequence analysis revealed that among the 13 strains studied, 11 belonged to the T. mentagrophytes complex. In detail, nine were classified as genotype I/II and two as genotype VII. Analysis of the SQLE gene revealed that nine strains harbored a wild-type gene, while two carried a Lys276Asn mutation. Genomic analysis was performed on three clinical T. mentagrophytes strains that belonged to genotype I/II, revealing the presence of different virulence factors including MEP-1, MEP-2, MEP-3, and MEP-5. Phylogenetic analysis based on core-genome SNPs demonstrated that the two genomes included in this study were clonally related to a T. mentagrophytes strain isolated in China in 2024. In conclusion, our study highlights the importance of genomic characterization in order to trace the epidemiology of dermatophytes worldwide and to characterize emerging strains. Full article

Background: Pancreas and pancreas–kidney transplantation are well-established therapeutic options for patients with type 1 diabetes mellitus (T1DM) and end-stage kidney disease (ESKD), offering the potential to restore endogenous insulin production and kidney function. It improves metabolic control, quality of life, and long-term survival. While surgical techniques and immunosuppressive strategies have advanced considerably, graft rejection and limited long-term graft survival remain significant clinical challenges. Method: To better understand these risks, the genetic and immunological factors that influence transplant outcomes are examined. Beyond traditional human leukocyte antigen (HLA) matching, non-HLA genetic variants such as gene deletions and single-nucleotide polymorphisms (SNPs) have emerged as contributors to alloimmune activation and graft failure. Result: Polymorphisms in cytokine genes, minor histocompatibility antigens, and immune-regulatory pathways have been implicated in transplant outcomes. However, the integration of such genomic data into clinical practice remains limited due to underexplored gene targets, variability in study results, and the lack of large, diverse, and well-characterized patient cohorts. Initiatives like the International Genetics & Translational Research in Transplantation Network (iGeneTRAiN) are addressing these limitations by aggregating genome-wide data from thousands of transplant donors and recipients across multiple centers. These large-scale collaborative efforts aim to identify clinically actionable genetic markers and support the development of personalized immunosuppressive strategies. Conclusions: Overall, genetic testing and genomics hold great promise in advancing precision medicine in pancreas and pancreas–kidney transplantation. Full article

Dysregulated inflammatory processes contribute to depression, and gene–environment interactions may influence an individual’s risk and resilience. Reduced brain-derived neurotrophic factor (BDNF) expression increases susceptibility for developing depressive symptoms, and the Val66Met (rs6265) single-nucleotide polymorphism (SNP) on the BDNF gene is linked to mood disorders. However, whether Val66Met confers increased vulnerability to inflammation-induced depressive tendencies is unknown. Here, we tested the hypothesis that the Val66Met SNP increases vulnerability to inflammation-induced depressive symptoms in a mouse model of lipopolysaccharide (LPS)-induced depression-like behavior. Behavior and neuroinflammation, following a 24 h LPS challenge, were measured in mice expressing the human BDNF Val66Met gene variant or Val66Val littermates (control). The Val66Met genotype did not affect the peripheral inflammatory response, acute neuroinflammation, or the acute sickness behavior response. Val66Met mice exhibited anhedonia-like behavioral responses following LPS challenge, and we found increased mRNA expression of IL-1β and TNFα in the cerebrum compared to controls. The mRNA expression of IL-1β and TNFα in the hippocampus and the nucleus accumbens of Val66Met mice was increased following LPS, and a significant genotype × LPS interaction was detected for CD68 expression in the nucleus accumbens. In summary, these data suggest that immune activation in Val66Met mice increased susceptibility to anhedonic behavior and dysregulated negative regulation of inflammation. Full article

This study identified four new keratin-associated protein genes (KRTAP19-n) in sheep: sKRTAP19-1, sKRTAP19-2, sKRTAP19-4, and sKRTAP19-6. These genes are closely related to the previously identified sheep genes KRTAP19-3 and KRTAP19-5, as well as to human KRTAP19-n genes. However, no clear orthologous relationships were found, suggesting complex evolutionary dynamics for this gene family. Extensive nucleotide sequence variation was observed across the four genes. sKRTAP19-1 had four variants, defined by four synonymous single-nucleotide polymorphisms (SNPs) and a variable number of “GGCTAC” hexanucleotide repeats. sKRTAP19-2 had five variants involving seven SNPs, three of which were non-synonymous. sKRTAP19-4 had five variants with nine SNPs (three being non-synonymous) and a three-nucleotide deletion. sKRTAP19-6 had eight variants, defined by 13 SNPs and a two-nucleotide consecutive substitution, with four of the SNPs being non-synonymous. One distinct variant each of sKRTAP19-4 and sKRTAP19-6 was found exclusively in Yanchi Tan sheep, with seven unique nucleotide differences compared to other variants. These unique variants were identical to the Romanov sheep genome in the region amplified (excluding the primer binding regions), suggesting a shared ancestral origin. The findings highlight considerable genetic diversity in ovine KRTAP19-n and lay a foundation for future research into their role in regulating wool fibre characteristics. Full article

Meiotic recombination is a key evolutionary process that generates novel allele combinations during prophase I of meiosis, promoting genetic diversity and enabling the selection of desirable traits in livestock breeding. Although its molecular mechanisms are well-characterised in model organisms such as humans and mice, studies in African indigenous cattle, particularly South African breeds, remain scarce. Key regulators of recombination, including PRDM9, SPO11, and DMC1, play essential roles in crossover formation and genome stability, with mutations in these genes often linked to fertility defects. Despite the Bonsmara and Nguni breeds’ exceptional adaptability to arid and resource-limited environments, little is known about how recombination contributes to their unique genetic architecture and adaptive traits. This review synthesises the current knowledge on the molecular basis of meiotic recombination, with a focus on prophase I events and associated structural proteins and enzymes. It also highlights the utility of genome-wide tools, particularly high-density single nucleotide polymorphism (SNP) markers for recombination mapping. By focusing on the underexplored recombination landscape in South African beef cattle, this review identifies key knowledge gaps. It outlines how recombination studies can inform breeding strategies aimed at enhancing genetic improvement, conservation, and the long-term sustainability of local beef production systems. Full article

Background/Objective: The present study focused on the analysis of the Spanish clone belonging to the successful 4,[5],12:i:- monophasic variant of Salmonella enterica serovar Typhimurium. Methods: All isolates of the clone recovered in a Spanish region from human clinical samples between 2008 and 2018 (N = 14) were investigated using microbiological approaches and genome sequence analysis. In addition, they were compared with isolates from the years 2000 to 2003 (N = 21), which were previously characterized but had not yet been sequenced. Results: Phylogenetic analyses indicate that all isolates are closely related (differing by 1 to 103 SNPs) but belong to two clades termed A and B. With few exceptions, clade A comprised isolates of the first period, also including two “older” control strains, LSP 389/97 and LSP 272/98. Clade B only contained isolates from the second period. Isolates from both periods were resistant to antibiotics and biocides, with almost all resistance genes located on large IncC plasmids, additionally carrying pSLT-derived virulence genes. The number of resistance genes was highly variable, resulting in a total of 22 ABR (antibiotic biocide resistance) profiles. The number of antibiotic resistance genes, but not that of biocide resistance genes, was considerably lower in isolates from the second than from the first period (with averages of 5.5 versus 9.6 genes). Importantly, IS26, which resides in multiple copies within these plasmids, appears to be playing a crucial role in the evolution of resistance, and it was also responsible for the monophasic phenotype, which was associated with four different deletions eliminating the fljAB region. Conclusions: the observed reduction in the number of antibiotic resistance genes could correlate with the loss of adaptive advantage originating from the ban on the use of antibiotics as feed additives implemented in the European Union since 2006, facilitated by the intrinsic instability of the IncC plasmids. Two consecutive IS26 transposition events, which can explain both the clonal relationship of the isolates and their variability, may account for the observed fljAB deletions. Full article

DNA-deaminase AID plays a pivotal role in adaptive immunity, antibody diversification and epigenetic regulation. AID catalyzes cytidine deamination in immunoglobulin genes, facilitating somatic hypermutation (SHM), class-switch recombination (CSR) and gene conversion (GC). However, the dysregulation of AID activity can lead to oncogenic mutations and immune disorders such as hyper-IgM syndrome type 2 (HIGM2). At present the number of studies investigating the role of AID polymorphic variants in the promotion of pathology is low. The current review examines the structural and functional aspects of AID, focusing on the impact of amino acid substitutions—both natural polymorphisms and artificial mutations—on its catalytic activity, substrate binding and interactions with regulatory proteins. Additionally, a bioinformatic analysis of single-nucleotide polymorphisms of AID deposited in the dbSNP database was performed. SNPs leading to amino acid substitutions in the primary protein structure were analyzed. The bioinformatic analysis of SNPs in the AID gene predicts that among 208 SNPs causing amino acid substitutions in the primary protein structure, 62 substitutions may have significant negative impact on the functioning of AID. The integration of computational predictions with experimental data underscores the importance of AID regulation in maintaining immune homeostasis and highlights potential markers for immune-related pathologies. This comprehensive analysis provides insights into the molecular mechanisms of AID dysfunction and its implications for disease. Full article

Single-cell RNA sequencing (scRNA-seq) enables expression quantitative trait locus (eQTL) analysis at cellular resolution, offering new opportunities to uncover regulatory variants with cell-type-specific effects. However, existing tools are often limited in functionality, input compatibility, or scalability for sparse single-cell data. To address these challenges, we developed scQTLtools, a comprehensive R/Bioconductor package that facilitates end-to-end single-cell eQTL analysis, from preprocessing to visualization. The toolkit supports flexible input formats, including Seurat and SingleCellExperiment objects, handles both binary and three-class genotype encodings, and provides dedicated functions for gene expression normalization, SNP and gene filtering, eQTL mapping, and versatile result visualization. To accommodate diverse data characteristics, scQTLtools implements three statistical models—linear regression, Poisson regression, and zero-inflated negative binomial regression. We applied scQTLtools to scRNA-seq data from human acute myeloid leukemia and identified eQTLs with regulatory effects that varied across cell types. Visualization of SNP–gene pairs revealed both positive and negative associations between genotype and gene expression. These results demonstrate the ability of scQTLtools to uncover cell-type-specific regulatory variation that is often missed by bulk eQTL analyses. Currently, scQTLtools supports cis-eQTL mapping; future development will extend to include trans-eQTL detection. Overall, scQTLtools offers a robust, flexible, and user-friendly framework for dissecting genotype–expression relationships in heterogeneous cellular populations. Full article

Background/Objectives: Sweet taste receptor TAS1R2 is expressed in skeletal muscle, yet its role in muscle metabolism remains poorly understood. Methods: Here, we leverage the BXD recombinant inbred mouse panel and Tas1r2 whole-body knockout (bKO) models to investigate the transcriptional impact of Tas1r2 deficiency on skeletal muscle function. Results: A gene network analysis revealed significant overlap in transcriptomic signatures between BXD strains with low Tas1r2 expression (BXD L_Tas1r2) and bKO muscle, particularly in pathways regulating oxidative phosphorylation, cytoplasmic ribosome function, and proteostasis. Notably, Tas1r2 expression negatively correlated with genes involved in fatty acid metabolism, suggesting its role in lipid utilization. Under high-fat diet (HFD) conditions, BXD_HFD L_Tas1r2 mice exhibited further enrichment in pathways linked to proteasome degradation, oxidative stress, and interleukin signaling, amplifying the transcriptomic convergence with bKO models. Key transcription factors (Mlxipl, Nfic, Rxrb) exhibited altered regulatory patterns under dietary stress, indicating that TAS1R2 influences metabolic adaptability through transcriptional reprogramming. Conclusions: Given that human TAS1R2 variants rarely result in complete loss of function (LOF), the BXD panel provides an effective dose-dependent model to bridge the gap between knockout phenotypes and human SNP carriers. Our findings establish TAS1R2 as a metabolic regulator in skeletal muscle and highlight the utility of genetically diverse mouse populations in dissecting gene-diet interactions relevant to human metabolic diseases. Full article

Citrobacter braakii can colonize the intestinal tract of humans and animals and occasionally act as opportunistic pathogen. Although isolated from food and the environment, its potential as a foodborne pathogen remains uncertain. Twenty C. braakii isolates were previously collected from salami and soft cheese artisanal productions. In the present study, the potentialities of C. braakii as a food safety hazard were explored by a genomic comparison of C. braakii newly sequenced genomes with publicly available genomes, including those of clinical relevance, and a pathogenicity assessment in Galleria mellonella as an in vivo infection model. Phylogenomic reconstruction revealed that one salami clone and two C. braakii genomes of the soft cheese production were closely related (from 11 to 28 core SNP differences) to C. braakii publicly available clinical genomes. All genomes carried the chromosomally located bla_CMY and/or qnrB genes and were resistant to cephalosporins and/or had reduced susceptibility to ciprofloxacin. G. mellonella larvae showed 90% mortality after challenge with C. braakii strains carrying the vex and tvi operons coding for the capsular polysaccharide (Vi antigen), in comparison to 40% of strains lacking these two operons. The high mortality rate of vex- and tvi-positive C. braakii isolated from food processing plants suggests C. braakii to be a possible foodborne hazard. Full article

Immunoassays for cardiac troponin, such as the Elecsys^® hs-TnT, have become the gold standard for myocardial infarction diagnostics. While various protein/chemical factors affecting the troponin complex and thus its diagnostic accuracy have been investigated, the role of coding single-nucleotide polymorphisms remains underexplored. To evaluate potential cSNP-induced interference with antibody binding in the Elecsys^® hs-TnT immunoassay, we applied ITEM-FOUR, a mass spectrometry-based method that quantifies changes in antibody binding upon amino acid substitutions in epitope peptides. Candidate cSNPs were selected from the dbSNP database and were mapped to human cardiac troponin T by molecular modeling. Consuming micromolar antibody concentrations and microliter sample volumes, two wild-type and 17 cSNP-derived variant epitope peptides—six for monoclonal antibody M7 and eleven for monoclonal antibody M11.7—were investigated to reveal the binding motifs “V₁₃₁-K₁₃₄-E₁₃₈-A₁₄₂” for M7 and “E₁₄₆-I₁₅₀-R₁₅₄-E₁₅₇” for M11.7. Loss of binding to M11.7 was observed for substitutions Q148R (rs730880232), R154W (rs483352832), and R154Q (rs745632066), whereas the E138K (rs730881100) exchange disrupted binding of M7. Except for cSNP Q148R, they are associated with cardiomyopathies, placing affected individuals at risk of both underlying heart disease and false-negative hs-TnT assay results in cases of myocardial infarction. Our results highlight the need to account for cSNP-related interferences in antibody-based diagnostics. ITEM-FOUR offers a powerful approach for tackling this challenge, fostering next-generation assay development. Full article

Background: Obesity, mainly visceral obesity, causes a low-grade of chronic inflammation (meta-inflammation), associated with comorbidities such as type 2 diabetes, cardiovascular diseases, and certain cancers. Precision Nutrition aims to understand the bidirectional crosstalk between the genome and diet to improve human health. Additionally, by leveraging individual data, Precision Nutrition seeks to predict how people will respond to specific foods or dietary patterns, with the ultimate goal of providing personalized nutritional recommendations tailored to their unique needs and lifestyle factors, including poor dietary habits (e.g., high intake of sugar or saturated fatty acids, alcohol consumption, etc.) and sedentary habits, exacerbate obesity in genetically predisposed individuals. Genetic, metabolic, and environmental factors can play a crucial role during obesity. Objective: To investigate the effects of genetic variability in sweet taste receptors and their downstream signaling pathways in the gut–brain axis on anthropometry, biochemistry, and lifestyle variables. Methods: A sample of 676 volunteers (mean age of 42.22 ± 12 years, ranging from 18 to 73 years) from the database of the GENYAL platform for nutritional trials at the IMDEA Food Institute were included in this study. We present a first-in-class genetic chip, Glucosensing, designed to interrogate 25 single-nucleotide polymorphisms (SNPs) located in genes encoding sweet taste receptors and components of downstream signaling pathways. These include elements of the gut–brain axis and its associated metabolic networks, enabling a comprehensive analysis of individual variability in sweet taste perception and metabolic responses. Results: Several significant associations were found after correction for multiple comparisons, representing potential targets for personalized interventions. Full article

Fatty acids (FAs), especially the polyunsaturated fatty acids (PUFAs), play pivotal roles in growth and development. Fish possess a remarkable ability to synthesize PUFAs, rendering them a crucial and significant source of these essential FAs for human consumption. Despite extensive research on the metabolic processes of FAs, the primary processes underlying FA content variation and corresponding regulatory mechanisms remain largely unexplored. We quantified the muscular FA profiles of 304 common carp samples. High variation in muscle FA content among samples was observed, with the coefficients of variation ranging from 0.36 to 0.92. With genome-wide association studies (GWAS), we identified 1410 SNPs significantly associated with the FA content. The genetic variation at genes participating in oxidation, ubiquitination, and transcriptional factors was associated with the content of multiple FAs, while few variants were observed in the FA-synthesis genes. For the total PUFA (TPUFA) content, transcriptome analysis of groups with the highest and lowest TPUFA content identified 715 differentially expressed genes (DEGs), including genes involved in oxidation and ubiquitination. Using multiple genomic selection programs with the associated SNPs for FA content, we obtained high and positive correlations ranging from 0.65 to 0.92 between the real FA contents and estimated breeding values. These findings manifested the major-effect processes governing the differences in muscular FA content and their regulatory mechanisms. The optimal genomic selection programs provide novel and feasible perspectives to enhance FA content in common carp. Full article

Background: Germline alleles near genes encoding certain immune checkpoints (CTLA4, CD200) are associated with autoimmune/autoinflammatory disease and cancer, but in opposite ways. This motivates a systematic search for additional germline alleles with this pattern with the aim of identifying potential cancer immunotherapeutic targets using human genetics. Methods: Pairwise fixed effect cross-disorder meta-analyses combining genome-wide association studies (GWAS) for breast, prostate, ovarian and endometrial cancers (240,540 cases/317,000 controls) and seven autoimmune/autoinflammatory diseases (112,631 cases/895,386 controls) coupled with in silico follow-up. Results: Meta-analyses followed by linkage disequilibrium clumping identified 312 unique, independent lead variants with p < 5 × 10⁻⁸ associated with at least one of the cancer types at p < 10⁻³ and one of the autoimmune/autoinflammatory diseases at p < 10⁻³. At each lead variant, the allele that conferred autoimmune/autoinflammatory disease risk was protective for cancer. Mapping led variants to nearest genes as putative functional targets and focusing on immune-related genes implicated 32 genes. Tumor bulk RNA-Seq data highlighted that the tumor expression of 5/32 genes (IRF1, IKZF1, SPI1, SH2B3, LAT) was each strongly correlated (Spearman’s ρ > 0.5) with at least one intra-tumor T/myeloid cell infiltration marker (CD4, CD8A, CD11B, CD45) in every one of the cancer types. Tumor single-cell RNA-Seq data from all cancer types showed that the five genes were more likely to be expressed in intra-tumor immune versus malignant cells. The five lead SNPs corresponding to these genes were linked to them via the expression of quantitative trait locus mechanisms and at least one additional line of functional evidence. Proteins encoded by the genes were predicted to be druggable. Conclusions: We provide population-scale germline genetic and functional genomic evidence to support further evaluation of the proteins encoded by IRF1, IKZF1, SPI1, SH2B3 and LAT as possible targets for cancer immunotherapy. Full article

Background: High-risk Escherichia coli clones, such as sequence type (ST)131 and ST1193, along with multidrug-resistant (MDR) Klebsiella pneumoniae, are globally recognized for their significant role in urinary tract infections (UTIs). This study aimed to provide an overview of the virulence factors, clonal diversity, and antibiotic resistance profiles of extended-spectrum cephalosporin (ESC)-E. coli and K. pneumoniae causing UTIs in humans in the Tebessa region of Algeria. Methods: Forty E. coli and 17 K. pneumoniae isolates exhibiting ESC-resistance were recovered (July 2022–January 2024) from urine samples of patients at three healthcare facilities to be phenotypically and genotypically characterized. Whole genome sequencing (WGS) was performed on the ST1193 clone. Results: Among K. pneumoniae isolates, all except one harbored CTX-M-15, with a single isolate carrying bla_CTX-M-194. Additionally, two K. pneumoniae isolates co-harboring bla_CTX-M-15 and bla_NDM exhibited phenotypic and genotypic hypervirulence traits. Fluoroquinolone resistance (FQR) was detected in 94.1% of K. pneumoniae isolates. The E. coli isolates carried diverse ESC-resistance genes, including CTX-M-15 (87.5%), CTX-M-27 (5%), CTX-M-1, CMY-59, and CMY-166 (2.5% each). Co-carriage of bla_ESC and bla_OXA-48 was identified in three E. coli isolates, while 62.5% exhibited FQR. Phylogenetic analysis revealed that 52.5% of E. coli belonged to phylogroup B2, including the high-risk clonal complex (CC)131 CH40-30 (17 isolates) and ST1193 (one isolate). In silico analysis of the ST1193 genome determined O75:H5-B2 (CH14-64), and the carriage of IncI1-I(Alpha) and IncF [F-:A1:B10] plasmids. Notably, core genome single-nucleotide polymorphism (SNP) analysis demonstrated high similarity between the Algerian ST1193 isolate and a previously annotated genome from a hospital in Northwest Spain. Conclusions: This study highlights the spread and genetic diversity of E. coli CC131 CH40-30 and hypervirulent K. pneumoniae clones in Algeria. It represents the first report of a CTX-M-15-carrying E. coli ST1193 in the region. The findings emphasize the urgent need for antibiotic optimization programs and enhanced surveillance to curb the dissemination of high-risk clones that pose an increasing public health threat in Algeria. A simplified method based on virulence traits for E. coli and K. pneumoniae is proposed here for antimicrobial resistance (AMR) monitoring. Full article