Search Results (5,234)

Background/Objectives: Late-onset Alzheimer’s disease (LOAD) is a multifactorial neurodegenerative disorder involving the interaction of genetic and environmental factors. Dysregulation of the fibrinolytic system, particularly an increase in plasminogen activator inhibitor-1 (PAI-1) levels, may contribute to Alzheimer’s pathology. Vitronectin (VTN) regulates fibrinolysis by stabilizing PAI-1. This study investigated the relationships between plasma PAI-1 activity and VTN, SERPINE1 (PAI-1), and APOE gene variants in nineteen LOAD patients (>65 years) and ten cognitively normal age-matched control groups. Methods: Targeted next-generation sequencing was used to analyze the VTN, APOE, and SERPINE1 genes in 19 LOAD patients and ten controls. Additionally, plasma PAI-1 activity was measured in both groups. Results: Plasma PAI-1 activity was statistically significantly higher in LOAD patients compared to controls (p = 0.04). Targeted next-generation sequencing results showed that VTN 5′-UTR variants (rs7212814, rs1555584131, rs71135830, and rs11437594) were found in all patients and observed in 20% of controls (p = 0.0001). The VTN rs704 variant was detected in 84% of patients and 29% of controls (p = 0.001). VTN 5′-UTR variants showed Spearman correlation with PAI-1 activity (r = 1.0; p < 0.0001). SERPINE1 3′-UTR variants (rs11178, rs41423845) were found to be associated with the disease (p = 0.027; p = 0.0001). The APOE ε3/ε4 genotype was present in 52.6% of patients and was not associated with PAI-1 activity. VTN variants showed an association with LOAD. Conclusions: These findings suggest that VTN variants may contribute to LOAD pathogenesis by affecting PAI-1 and leading to fibrinolytic system dysregulation. Full article

Hepatitis B virus (HBV) is the smallest partially double-stranded, reverse-transcribing DNA virus, with four open reading frames (ORFs) encoding viral proteins. It is classified into nine geographically distributed genotypes (A–I). In Kenya, the molecular characterization of HBV among patients seeking medical care remains poorly defined. This observational study aimed to characterize HBV among patients seeking medical care in Kenya’s endemic region, focusing on circulating genotypes and ORF mutations. Serum samples were collected from the outpatient departments of selected health facilities, with demographic and clinical information extracted from patients’ medical records. Hepatitis B surface antigen (HBsAg) was tested at the facilities, and 85 HBsAg-positive samples were collected for molecular analysis. The basal core promoter and pre-core (BCP/PC), polymerase, and surface regions of the viral genome were amplified and sequenced to determine genotypes and to profile their mutations. Out of 85 HBsAg-positive samples, 38 samples tested positive for HBV DNA, and 26 samples were successfully sequenced. HBV genotype A was prevalent at 73.1% (19/26), followed by genotype D at 23.1% (6/26), and genotype E at 3.8% (1/26). Genotype A sequences clustered with both A1 Asian and African subgenotypes, whereas genotype D clustered with subgenotypes D6 and D1. All HBV genotype A, D, and E sequences were serotypes adw2, ayw2, and ayw4, respectively. HBV core promoter mutations (A1762T/G1764A) were detected in both genotype D and genotype A isolates. The pre-core G1896A mutation was highly prevalent in genotype D samples (5/6; 83.3%) but was not observed in genotypes A or E. Analysis of mutations within the “a” determinant region revealed genotype-specific patterns: genotype A predominantly harbored V14A, P46H, S58C, and P67Q substitutions; genotype E showed N59S; and genotype D exhibited V14A, C69stop, S104T, and W182stop mutations. Two drug resistance mutations (V191I and A194T) were present in two chronic patients, one with genotype A and the other with genotype D. In conclusion, HBV genotypes A and D are the most prevalent among Kenyan patients with chronic HBV infection. The presence of point mutations in the ORFs among patients seeking medical care highlights the need for molecular surveillance to better understand the viral diversity and its potential clinical and public health implications. Full article

Background/Objectives: Eleocharis ussuriensis Zinserl. is a perennial riparian sedge widely distributed in Northeast Asia and a dominant component of freshwater vegetation in South Korea. However, the intraspecific genetic structure of this species across contrasting hydrological habitats remains insufficiently understood. This study aimed to develop novel SSR markers from whole-genome data and investigate genetic variation and population structure among E. ussuriensis populations in South Korea. Methods: Twenty-one novel simple sequence repeat (SSR) markers were developed from whole-genome sequence data and applied to analyze genetic variation in 120 individuals from 6 populations. Genetic diversity, differentiation, and gene flow were estimated using allele-frequency-based metrics, and population genetic structure was further evaluated using spatial information derived from geographic coordinates. Results: A total of 201 alleles were detected, with a mean polymorphism information content (PIC) of 0.759, indicating high marker informativeness. Mean genetic diversity across populations showed observed heterozygosity (Ho = 0.360) and expected heterozygosity (He = 0.281), while multilocus genotype ratios (G/N) ranged from 0.30 to 1.00 among populations. Genetic differentiation was substantial (F_ST = 0.373–0.669; Jost’s D = 0.540–0.997). Mantel tests revealed that genetic differentiation was significantly correlated with geographic distance (r = 0.67, p < 0.001). Both allele-frequency-based and spatially explicit approaches suggested genetic structuring among populations. Conclusions: The results suggest spatial tendencies in genetic structure among populations, reflecting patterns of allele distribution across regions. These findings provide baseline information on genetic variation in E. ussuriensis and may contribute to a better understanding of its ecological dynamics. Full article

Background/Objectives: Staphylococcus aureus, particularly methicillin-resistant strains, is a leading cause of severe pneumonia. Understanding local molecular epidemiology, including virulence gene profiles and antimicrobial resistance (AMR) mechanisms, is crucial for effective infection control. This pilot study aimed to characterize S. aureus isolates from pneumonia patients in Karaganda, Kazakhstan. Methods: We collected 48 respiratory samples from patients with pneumonia across three medical institutions. Bacterial identification was performed using MALDI-TOF MS. Antimicrobial susceptibility testing (AST) was carried out using European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. Whole-genome sequencing of S. aureus isolates was conducted on an Ion Torrent S5 platform. Genomic analysis included multilocus sequence typing (MLST), identification of virulence and AMR genes, and phylogenetic reconstruction. Results: S. aureus was identified in 14.6% (n = 7) of pneumonia cases included in this study. All isolates (100%, n = 7) were phenotypically resistant to benzylpenicillin. The mecA gene was detected in 57.1% of isolates (n = 4), while phenotypic resistance to methicillin was observed in 28.6% (n = 2) of the isolates. Resistance to azithromycin (57.1%, n = 4) and levofloxacin (42.9%, n = 3) was observed among the isolates. Two isolates (28.6%) were multidrug-resistant (MDR). Genomic analysis revealed the prevalence of the ST22 clone (57.1%, n = 4) in the studied cohort. Other sequence types were ST97, ST8, and ST45 (14.3% each). Phylogenetic analysis showed clustering consistent with MLST profiles. All isolates carried a conserved core virulence arsenal, including hemolysin (hla, hlg), biofilm-forming genes (icaADBC), immune evasion genes (sak, scn), and iron acquisition genes (isd). The Panton–Valentine leukocidin (PVL) genes were detected in three isolates. AMR gene analysis revealed the ubiquitous presence of mepA and tetracycline efflux pump genes, along with regulatory genes (arlRS, mepR, mgrA). The blaZ and ermA genes were not detected despite high phenotypic resistance to penicillin and macrolides. Conclusions: This study reports the identification of the virulent and resistant ST22 S. aureus clone in pneumonia cases in Karaganda, Kazakhstan. The discordance between phenotypic and genotypic AMR profiles underscores the necessity for integrated diagnostic approaches. Full article

Staphylococcus aureus is a high-priority pathogen causing skin and soft tissue infections (SSTIs). The frequent resistance to anti-staphylococcal agents exhibited by this underscores the need for accurate diagnostics to guide effective therapy. Therefore, this study aimed to compare phenotypic and genotypic resistance in S. aureus isolates from nasal carriers and SSTIs and to elucidate gene-silencing mechanisms. In total, 355 S. aureus isolates (256 isolated from carriers and 79 from SSTIs) were studied for their phenotypic and genotypic resistance to β-lactams, macrolides, tetracyclines, aminoglycosides, and mupirocin. The silenced mupA gene (low prevalence: 0.6%; 2/335), linked to mupirocin resistance, was sequenced, and expression was assessed via reverse transcription qualitative PCR (RT-qPCR) in all mupA-positive isolates. SSTI isolates showed significantly higher resistance to erythromycin, gentamicin, and mupirocin, along with a higher prevalence of multidrug-resistant strains and ermC and tetM genes. Sequencing revealed multiple mutations in silent mupA, including a critical frameshift (c.372 delA) in a poly(A) tract that brings about premature truncation. RT-qPCR indicated upregulation of silent mupA variants and high variability in functional strains, suggesting that frameshift alone prevents resistance. These findings highlight silent resistance genes as key targets for advancing S. aureus surveillance and for combating emerging threats. Full article

Cystic echinococcosis (CE) is caused by a tapeworm of the Echinococcus granulosus s.l. species complex belonging to the Taeniidae family. CE affects more than 100 countries, including Poland, while remaining a significant public health threat to both humans and livestock. The aim of this study was to identify the genotypes responsible for cases of cystic echinococcosis in Poland by conducting molecular analysis of larvae isolated from Polish patients, and to investigate the diagnostic pathways leading to CE diagnosis. Between April 2023 and January 2025, tissue samples were collected from 10 patients following hepatectomy. Analysis of diagnostic pathways revealed that radiological findings followed by PCR or histopathological testing were sufficient to establish a reliable diagnosis of CE in 90% and 100% of cases, respectively. Serological tests showed lower sensitivity, reaching 86% for ELISA and 71% for Western blot. DNA extracted from all samples was used as the template in PCR to amplify and sequence the region of the mitochondrial NADH dehydrogenase 1 gene (nad1). PCR analysis confirmed presence of Echinococcus granulosus s.l. species in eight cases. All obtained nad1 sequences showed identity with the Echinococcus canadensis G7 (pig) strain. These results indicate that it remains the most frequent causative agent of human cystic echinococcosis in Poland. Full article

Genotyping is a key step in molecular breeding. Due to its cost-effectiveness, accuracy, and flexibility, genotyping by target sequencing (GBTS) has become a preferred technology for medium-density genotyping. In this study, a new GBTS array for fresh edible maize was developed using resequencing data from 477 lines. The array contains 5759 SNPs evenly distributed across the maize genome, with average minor allele frequency (MAF) and polymorphism information content (PIC) values of 0.40 and 0.36, respectively. These SNPs are closely associated with 1566 functional genes. Cluster analysis of 198 maize lines based on the GBTS array was consistent with their pedigree relationships. Furthermore, 277 fresh waxy maize lines were genotyped and used for genomic selection analyses of hundred-kernel weight, kernel length, and kernel width. Comparative evaluation of different models indicated that Ridge Regression Best Linear Unbiased Prediction (rrBLUP) was the optimal model, with prediction accuracies of 0.33, 0.64, and 0.36, respectively. Additional analyses using different marker densities based on the rrBLUP model showed that prediction accuracy did not increase when the number of markers exceeded 2000, indicating that this array provides sufficient marker density for genetic analysis and genomic selection. Overall, this array provides a useful tool for genetic studies of fresh edible maize and facilitates the application of genomic selection in breeding programs. Full article

Avian reovirus (ARV) causes viral arthritis and leads to considerable economic losses in the poultry industry. In this study, six ARV strains of distinct genotypes (FJNP01–FJNP06) were isolated from commercial broiler farms. Through gene sequencing and pathogenicity assessment, we analyzed the genetic evolution and pathogenic characteristics of the σC, P10, σB, μB, and λC genes. Pathogenicity tests revealed that inoculation with FJNP01–FJNP06 by footpad or oral gavage induced symptoms in specific-pathogen-free (SPF) chickens, including mortality and growth retardation. Among the isolates, FJNP04 (genotype IV) showed the highest pathogenicity, causing increased mortality, weight loss, and severe lesions in the footpads and bursa of Fabricius, followed by FJNP05 and FJNP02. The pathogenicity of FJNP06 varied by inoculation route, with enhanced pathogenicity observed following oral gavage. In contrast, FJNP01 and FJNP03 demonstrated relatively low pathogenicity. Identity analysis indicated that σC and P10 were highly variable, σB was relatively conserved, while μB and λC displayed considerable divergence. Phylogenetic analysis placed FJNP01–FJNP06 into genotypes I to VI, respectively, forming six distinct branches on the σC and P10 phylogenetic trees, yet clustering more closely on the σB, μB, and λC trees. The pathogenicity of different genotypes of ARV varies, among which FJNP04 (genotype IV) exhibits the strongest pathogenicity. Genetic sequence analysis revealed that σC and P10 are highly variable, σB is relatively conserved, while μB and λC display a wide range of variation. This study provides insights into the genetic variation and pathogenic characteristics of ARV and serves as a reference for future research. Full article

Chinese cabbage is one of the major vegetable crops in northern Asia. Its leaves are the major organ for photosynthesis and production, and leaf color directly influences its yield and quality. Here, we obtained a pale green mutant pgm3. This mutant line was derived from EMS mutagenesis of Chinese cabbage DH line FT. pgm3 exhibited chlorosis and etiolation, delayed growth, reduced photosynthetic pigment content and net photosynthetic rates, and impaired development of the chloroplast inner membrane system. Genetic analysis revealed that the pale green phenotype was controlled by a single recessive nuclear gene, Brpgm3. Mutmap analysis indicated that Brpgm3 is located on a 13.9 Mb region in A03. Within this region, a single SNP (A03: 7194530) with an SNP-index of 1, located in BraA03g015750.3C (BrClpC1), was identified from 40 differential SNPs. KASP genotyping demonstrated that the SNP co-segregated with the pale green phenotype in the F₂ population. Sanger sequencing confirmed a G-to-A SNP in exon 4 of BrClpC1, which resulted in an amino acid substitution from S to G. Furthermore, multiple sequence alignment of homologs from 28 species demonstrated that this mutated residue is highly conserved. BrClpC1 was predominantly expressed in leaves and exhibited the highest transcript abundance among the nine members of the Class I Clp gene family in Brassica rapa. This is the first report identifying ClpC1 in Brassica crops. Our results not only confirmed BrClpC1 as a strong candidate gene for the pale green mutant of Chinese cabbage, but also highlighted BrClpC1 as a target for chloroplast biology research in Brassica crops. Full article

Bovine rotavirus (BRV) poses a major threat to the global cattle industry, driving significant morbidity and mortality in young calves. In Yunnan Province, China, BRV is the primary cause of neonatal calf diarrhea (NCD), yet the molecular epidemiology of circulating strains remains poorly understood. This study aimed to investigate the molecular characteristics of bovine rotavirus strains associated with a severe outbreak of the NCD on a local farm. Fecal samples were collected from 396 calves and screened for BRV by RT-PCR targeting the VP6 gene. Positive samples were subjected to virus isolation in MA104 cells, followed by whole-genome sequencing, phylogenetic analysis, and pathogenicity assessment in suckling mice. Of 396 samples, 85 tested positive for BRV, corresponding to an animal-level prevalence of 21.5% (95% CI: 17.5–25.8%), with four fatalities recorded. A strain designated as BRV-YN1-2021 was successfully isolated, exhibiting characteristic cytopathic effects, specific immunofluorescence, and typical rotavirus morphology by electron microscopy. Genomic analysis revealed the constellation G8-P[1]-I2-R2-C2-M2-A3-N2-T6-E2-H3, identified as genotype G8P[1]. BLAST analysis showed that four genomic segments shared the highest identity with deer rotavirus strains, five with human rotavirus strains, and two with bovine rotavirus strains. Phylogenetic analysis demonstrated close relationships with US deer strains, Japanese bovine strains, and human strains circulating in China. Experimental infection in suckling mice induced diarrhea and significant intestinal histopathology, degeneration of villous epithelial cells, goblet cell hyperplasia, and inflammatory infiltration. This study reports the first isolation of a G8P[1] bovine rotavirus from a diarrhea outbreak in Chinese cattle. The multi-host genetic composition provides evidence of interspecies reassortment events, highlighting the zoonotic potential of BRV and emphasizing the need for continuous molecular surveillance to inform effective control strategies. Full article

Background/Objectives: The Korean Global Antimicrobial Resistance Surveillance System monitors bloodstream Staphylococcus aureus infections by combining antimicrobial susceptibility testing (AST) with conventional polymerase chain reaction (PCR). Considering the clinical significance of methicillin-resistant S. aureus (MRSA), we performed an in-depth analysis of isolates showing genotypic–phenotypic discrepancies. Methods: Isolates were collected from designated collection centers in the Republic of Korea between 2017 and 2024. The 30 μg cefoxitin disk diffusion method was used to define the phenotypes. PCR targeting mecA and the staphylococcal cassette chromosome mec (SCCmec) was used to identify genotypes through gel electrophoresis. Long-read whole-genome sequencing (WGS) was performed using the Revio system (Pacific Biosciences) for isolates exhibiting discrepancies between phenotypes and genotypes. Results: In total, 5808 isolates were screened, and seven cases of genotypic–phenotypic discrepancies were identified, including one infant and six elderly patients with chromosomal SCCmec type IV. Although WGS confirmed intact PCR primer-binding sites, structural alterations were observed: three isolates had normal-length mecA and mecR1, two had partial deletions in mecA, and two featured either mecA or mecR1 split into two proteins. Notably, although the six isolates with intact mecR1 genes matched the nucleotide length of SCCmec type IV, their sequences exhibited high homology with SCCmec type II. Conclusions: Despite the presence of mecA, the non-standard configuration of regulatory genes within the SCCmec elements suppressed actual resistance expression. Because conventional PCR focusing on partial gene segments could overlook such phenotypic traits, the meticulous observation and implementation of WGS are crucial for the accurate characterization of genotypic–phenotypic discrepancies. Full article

Salt stress represents a significant abiotic stress factor that adversely affects plant growth and development. It directly inhibits both vegetative and reproductive growth, resulting in substantial reductions in crop yield and quality. Consequently, the identification of salt tolerance genes and the elucidation of their underlying molecular mechanisms are crucial for improving crop salt tolerance and ensuring agricultural productivity. To investigate the molecular basis underlying differential salt tolerance between Zheng58 and PH4CV, we employed pooled sequencing (BSA-seq) using extreme phenotypic individuals from their F₂ population and conducted a comparative transcriptome analysis at the seedling stage of the two genotypes. Phenotypic, physiological, biochemical, and ion content analyses revealed that Zheng58 exhibited significantly superior performance compared to PH4CV under salt stress conditions. BSA-seq analysis identified six genomic regions associated with salt tolerance, encompassing a total of 391 genes. Functional annotation enabled the screening of 151 candidate genes potentially involved in salt stress responses. Transcriptome profiling indicated that differentially expressed genes were significantly enriched in biological processes, particularly plant hormone signal transduction and MAPK signaling pathways. Integrating BSA-seq and transcriptome data, key candidate gene ZmACC2 (Zm00001eb419400) was identified as potentially involved in the regulation of salt tolerance in maize. This gene may modulate Na⁺/K⁺/Ca²⁺ homeostasis and reactive oxygen species metabolism through defense responses mediated by ethylene (ETH) and hydrogen peroxide, as well as through ion homeostasis regulatory pathways. This study provides valuable candidate genes and a theoretical foundation for further dissection of the molecular mechanisms governing salt tolerance in maize. Full article

Background/Objectives: Population-specific genomic data are essential for understanding hepatocellular carcinoma (HCC) biology, particularly in underrepresented regions. This study aimed to perform exploratory single-nucleotide polymorphism (SNP)-array-based profiling of HCC tumor samples from Indonesian patients and to prioritize candidate functional variants using a systematic in silico framework. Methods: This retrospective cross-sectional study included 15 resected HCC cases with available formalin-fixed paraffin-embedded (FFPE) tumor tissue. Genome-wide SNP genotyping was performed using the Illumina Asian Screening Array. Following quality control and filtering, variants were annotated using the Ensembl Variant Effect Predictor. A case-only functional prioritization approach incorporating multiple in silico prediction tools was applied, followed by gene-level burden aggregation. Results: After multistep filtering, 11 samples and 104 prioritized variants were retained for analysis. Variants consisted predominantly of splice-region, missense, and regulatory changes. Gene-level burden analysis identified Nuclear Autoantigenic Sperm Protein (NASP, rs775916096) as the highest-ranked candidate gene, while G protein-coupled receptor 78 (GPR78, rs558447540) emerged as a secondary candidate with predicted functional annotations but currently limited biological evidence in HCC. Given the tumor-only design without matched normal tissue, the prioritized variants cannot be distinguished from rare germline variants. Conclusions: This exploratory SNP-array study provides a hypothesis-generating framework for functional variant prioritization in Indonesian HCC. NASP and GPR78 represent preliminary candidates that require validation in larger cohorts with matched normal tissue and sequencing-based confirmation. Full article

Congenital factor V (FV) deficiency is a rare autosomal recessive bleeding disorder caused by pathogenic variants in F5 gene and characterized by heterogeneous clinical manifestations. The aim of this study was to define the mutational spectrum of F5 in Russian patients with congenital FV deficiency. We analyzed 16 unrelated patients with different disease severity and 9 relatives from five families. All functionally relevant regions of F5 were examined by Sanger sequencing. Multiplex ligation-dependent probe amplification (MLPA) was used to detect large deletions and duplications. Whole-genome sequencing and functional cDNA analysis were performed in selected cases. This study represents the first description of the F5 mutational spectrum in a Russian cohort. We identified 12 novel variants and demonstrated the functional effect of two previously unreported variants located outside canonical splice-site dinucleotides, leading to aberrant splicing. Notably, the proportion of variants undetectable by routine diagnostic approaches was higher than that reported in other populations. No clear genotype–phenotype correlation was observed. Despite the limited sample size, our findings expand current knowledge of the molecular basis of congenital FV deficiency and may improve genetic diagnostics in Russia. Full article

Background: Glutaric acidemia type 1 (GA1) is an autosomal recessive neurometabolic disorder caused by pathogenic variants in glutaryl-CoA dehydrogenase (GCDH), with variable clinical severity despite early biochemical detectability. Population-specific mutational spectra and genotype–phenotype correlations remain insufficiently defined in infantile-onset disease. Therefore, this study aimed to define the GCDH variant spectrum in GA1 patients with mild hepatopathy and assess genotype–phenotype correlations. Methods: We performed integrated clinical, biochemical, and molecular characterization of 15 unrelated patients with infantile-onset GA1. Whole-exome sequencing (WES) was performed for all participants, and the resulting data were compared with the reference sequence of the GCDH gene. Results: All patients presented within the first 6 months of life with macrocephaly, seizures, dystonia, and feeding difficulties. Neurological impairment and mild hepatopathy were variably observed, and one patient developed an acute encephalopathic crisis. Six homozygous GCDH variants were identified, predominantly missense. A common variant, c.541G>C (p.Glu181Gln), accounted for 73.3% of cases and defined a consistent phenotype of early macrocephaly and movement disorder with frequent mild hepatic involvement, suggesting regional enrichment and raising the possibility of a founder effect that warrants confirmation in future haplotype studies. A truncating variant, c.382C>T (p.Arg128Ter), was associated with severe early encephalopathy. Exon 6 represented a mutational hotspot. Biochemically, all patients showed elevated urinary glutaric and 3-hydroxyglutaric acids, increased glutarylcarnitine, and low-to-normal free carnitine, with higher metabolite levels in clinically more severe cases. All variants were pathogenic or likely pathogenic and extremely rare in population databases. Conclusions: This cohort reveals a striking predominance of the GCDH c.541G>C variant and establishes a clear biochemical signature with genotype-associated clinical patterns in infantile-onset GA1. These findings support a population-specific mutational spectrum, refine genotype–phenotype correlations, and underscore the importance of early molecular diagnosis to guide targeted neurological and hepatic monitoring as well as regional screening strategies. Full article