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1.
Sci Rep ; 14(1): 10932, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740892

RESUMO

SINE-VNTR-Alu (SVA) retrotransposons are transposable elements which represent a source of genetic variation. We previously demonstrated that the presence/absence of a human-specific SVA, termed SVA_67, correlated with the progression of Parkinson's disease (PD). In the present study, we demonstrate that SVA_67 acts as expression quantitative trait loci, thereby exhibiting a strong regulatory effect across the genome using whole genome and transcriptomic data from the Parkinson's progression markers initiative cohort. We further show that SVA_67 is polymorphic for its variable number tandem repeat domain which correlates with both regulatory properties in a luciferase reporter gene assay in vitro and differential expression of multiple genes in vivo. Additionally, this variation's utility as a biomarker is reflected in a correlation with a number of PD progression markers. These experiments highlight the plethora of transcriptomic and phenotypic changes associated with SVA_67 polymorphism which should be considered when investigating the missing heritability of neurodegenerative diseases.


Assuntos
Elementos Alu , Progressão da Doença , Repetições Minissatélites , Doença de Parkinson , Polimorfismo Genético , Retroelementos , Doença de Parkinson/genética , Humanos , Repetições Minissatélites/genética , Retroelementos/genética , Elementos Alu/genética , Locos de Características Quantitativas , Biomarcadores , Elementos Nucleotídeos Curtos e Dispersos/genética
2.
PLoS Negl Trop Dis ; 18(4): e0012143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38662795

RESUMO

Trachoma is the leading infectious cause of blindness worldwide and is now largely confined to around 40 low- and middle-income countries. It is caused by Chlamydia trachomatis (Ct), a contagious intracellular bacterium. The World Health Organization recommends mass drug administration (MDA) with azithromycin for treatment and control of ocular Ct infections, alongside improving facial cleanliness and environmental conditions to reduce transmission. To understand the molecular epidemiology of trachoma, especially in the context of MDA and transmission dynamics, the identification of Ct genotypes could be useful. While many studies have used the Ct major outer membrane protein gene (ompA) for genotyping, it has limitations. Our study applies a typing system novel to trachoma, Multiple Loci Variable Number Tandem Repeat Analysis combined with ompA (MLVA-ompA). Ocular swabs were collected post-MDA from four trachoma-endemic zones in Ethiopia between 2011-2017. DNA from 300 children with high Ct polymerase chain reaction (PCR) loads was typed using MLVA-ompA, utilizing 3 variable number tandem repeat (VNTR) loci within the Ct genome. Results show that MLVA-ompA exhibited high discriminatory power (0.981) surpassing the recommended threshold for epidemiological studies. We identified 87 MLVA-ompA variants across 26 districts. No significant associations were found between variants and clinical signs or chlamydial load. Notably, overall Ct diversity significantly decreased after additional MDA rounds, with a higher proportion of serovar A post-MDA. Despite challenges in sequencing one VNTR locus (CT1299), MLVA-ompA demonstrated cost-effectiveness and efficiency relative to whole genome sequencing, providing valuable information for trachoma control programs on local epidemiology. The findings suggest the potential of MLVA-ompA as a reliable tool for typing ocular Ct and understanding transmission dynamics, aiding in the development of targeted interventions for trachoma control.


Assuntos
Proteínas da Membrana Bacteriana Externa , Chlamydia trachomatis , Genótipo , Repetições Minissatélites , Tracoma , Chlamydia trachomatis/genética , Chlamydia trachomatis/isolamento & purificação , Chlamydia trachomatis/classificação , Tracoma/epidemiologia , Tracoma/microbiologia , Tracoma/tratamento farmacológico , Humanos , Etiópia/epidemiologia , Repetições Minissatélites/genética , Proteínas da Membrana Bacteriana Externa/genética , Feminino , Masculino , Pré-Escolar , Tipagem Molecular/métodos , Azitromicina/uso terapêutico , Variação Genética , Lactente , Criança , Antibacterianos/farmacologia , DNA Bacteriano/genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-37610137

RESUMO

OBJECTIVE: Circadian rhythmicity has been shown to contribute to the regulation of key physiological and cognitive processes related to performance. The period homolog 3 (PER3) is expressed in a circadian pattern in the suprachiasmatic nucleus. Therefore, in this study, we aimed to evaluate the role of the variable tandem repeat (VNTR) variant of the PER3 gene in athletic performance in the Turkish population. METHODS: This study included 223 subjects, which consisted of 123 athletes and 100 sedentary controls. Blood samples were drawn from all subjects. DNA was extracted from whole-blood samples. The PER3 VNTR variant was genotyped using the polymerase chain reaction-restriction method (PCR). The results of the analyses were evaluated for statistical significance. RESULTS: The mean ages of athletes and controls were 22 ± 2.814 and 23 ± 3.561, respectively. Endurance athletes in the group were 21.1%, and sprint athletes were 78.9%. There was no statistical significance in terms of PER3 VNTR genotype distribution or allele frequency. In the recessive model, a statistically significant association was observed when the athletes were compared with the controls according to 4/4 + 4/5 versus 5/5 genotype (p = 0.020). CONCLUSION: In this case-control study, for the first time in our country, we obtained findings suggesting that the PER3 VNTR variant may affect sports performance in the Turkish population. Results need to be replicated in different ethnic and larger samples.


Assuntos
Repetições Minissatélites , Polimorfismo Genético , Humanos , Repetições Minissatélites/genética , Estudos de Casos e Controles , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Ritmo Circadiano/genética , Frequência do Gene , Genótipo , Atletas
4.
Asian J Psychiatr ; 91: 103831, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37988928

RESUMO

OBJECTIVE: There seems to be an association between the DRD4 48-bp VNTR polymorphisms and antipsychotic treatment response, but there is a rare reference to confirm this finding. Hence, the present study tried to investigate the association between DRD4 48-bp VNTR polymorphisms and the treatment response of antipsychotics in patients with schizophrenia in Taiwan, using a propensity score matching (PSM) method. METHODS: A total of 882 participants were enrolled in this study and completed informed consent, research questionnaires, including demographic information and the revised Chinese version Beliefs about Voices Questionnaire, and blood sampling. For descreasing of the selection bias and confounding variables, the PSM nearest neighbor matching method was used to select 765 paitents with schizophrenia (ratio of 1:8 between 85 persistent auditory hallucination and 680 controls) with matched and controlled the age and gender. RESULTS: Schizophrenia patients with DRD4 4 R homozygosity had a lower rate of good antipsychotic treatment response than the other DRD4 genotype carriers (DRD4 non-4/4). Among those 4 R homozygosity carriers, 60 cases of 503 (11.9%) retain persistent auditory hallucinations. Furthermore, this subgroup of patients is accounted for up to 70.6% of cases with poor neuroleptic treatment response. CONCLUSIONS: A poor treatment outcome for patients with the 4 R homozygosity had presented,that comparing with those DRD non-4/4 genotype carriers. DRD4 VNTR 4 R homozygosity could be a genetic biomarker to predict poor antipsychotic treatment response in schizophrenia. Patients with DRD 4/4 probably receive novel antipsychotic medications preferentially or in combination with alternative therapy, such as psychotherapy or milieu therapy.


Assuntos
Antipsicóticos , Esquizofrenia , Humanos , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética , Antipsicóticos/uso terapêutico , Receptores de Dopamina D4/genética , Repetições Minissatélites/genética , Genótipo , Alucinações/genética , Alucinações/tratamento farmacológico , Biomarcadores
5.
BMC Genomics ; 24(1): 690, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978434

RESUMO

BACKGROUND: As a population genetic tool, mitochondrial DNA is commonly divided into the ~ 1-kb control region (CR), in which single nucleotide variant (SNV) diversity is relatively high, and the coding region, in which selective constraint is greater and diversity lower, but which provides an informative phylogeny. In some species, the CR contains variable tandemly repeated sequences that are understudied due to heteroplasmy. Domestic cats (Felis catus) have a recent origin and therefore traditional CR-based analysis of populations yields only a small number of haplotypes. RESULTS: To increase resolution we used Nanopore sequencing to analyse 119 cat mitogenomes via a long-amplicon approach. This greatly improves discrimination (from 15 to 87 distinct haplotypes in our dataset) and defines a phylogeny showing similar starlike topologies within all major clades (haplogroups), likely reflecting post-domestication expansion. We sequenced RS2, a CR tandem array of 80-bp repeat units, placing RS2 array structures within the phylogeny and increasing overall haplotype diversity. Repeat number varies between 3 and 12 (median: 4) with over 30 different repeat unit types differing largely by SNVs. Five SNVs show evidence of independent recurrence within the phylogeny, and seven are involved in at least 11 instances of rapid spread along repeat arrays within haplogroups. CONCLUSIONS: In defining mitogenome variation our study provides key information for the forensic genetic analysis of cat hair evidence, and for the first time a phylogenetically informed picture of tandem repeat variation that reveals remarkably dynamic mutation processes at work in the mitochondrion.


Assuntos
Genoma Mitocondrial , Gatos/genética , Animais , Variação Genética , Repetições Minissatélites/genética , Mitocôndrias , Mutação
6.
Vet Microbiol ; 287: 109909, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37925876

RESUMO

Mycoplasma iowae is a worldwide spread and economically important avian pathogen that mostly infects turkeys. Currently, multi-locus sequence typing (MLST) serves as the gold standard method for strain identification in M. iowae. However, additional robust genotyping methods are required to effectively monitor M. iowae infections and conduct epidemiological investigations. The first aim of this study was to develop genotyping assays with high resolution, that specifically target M. iowae, namely a multiple-locus variable number of tandem-repeats analysis (MLVA) and a core genome multi-locus sequence typing (cgMLST) schema. The second aim was the determination of relationships among a diverse selection of M. iowae strains and clinical isolates with a previous and the newly developed assays. The MLVA was designed based on the analyses of tandem-repeat (TR) regions in the six serotype reference strains (I, J, K, N, Q and R). The cgMLST schema was developed based on the coding sequences (CDSs) common in 95% of the examined 99 isolates. The samples were submitted for a previously published MLST assay for comparison with the developed methods. Out of 94 TR regions identified, 17 alleles were selected for further evaluation by PCR. Finally, seven alleles were chosen to establish the MLVA assay. Additionally, whole genome sequence analyses identified a total of 676 CDSs shared by 95% of the isolates, all of which were included into the developed cgMLST schema. The MLVA discriminated 19 distinct genotypes (GT), while with the cgMLST assay 79 sequence types (ST) could be determined with Simpson's diversity indices of 0.810 (MLVA) and 0.989 (cgMLST). The applied assays consistently identified the same main clusters among the diverse selection of isolates, thereby demonstrating their suitability for various genetic analyses and their ability to yield congruent results.


Assuntos
Mycoplasma iowae , Animais , Tipagem de Sequências Multilocus/métodos , Tipagem de Sequências Multilocus/veterinária , Genótipo , Técnicas de Genotipagem/veterinária , Sequências de Repetição em Tandem , Repetições Minissatélites/genética , Filogenia
7.
Nucleic Acids Res ; 51(21): 11453-11465, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37823611

RESUMO

SINE-VNTR-Alu (SVA) retrotransposons are evolutionarily young and still-active transposable elements (TEs) in the human genome. Several pathogenic SVA insertions have been identified that directly mutate host genes to cause neurodegenerative and other types of diseases. However, due to their sequence heterogeneity and complex structures as well as limitations in sequencing techniques and analysis, SVA insertions have been less well studied compared to other mobile element insertions. Here, we identified polymorphic SVA insertions from 3646 whole-genome sequencing (WGS) samples of >150 diverse populations and constructed a polymorphic SVA insertion reference catalog. Using 20 long-read samples, we also assembled reference and polymorphic SVA sequences and characterized the internal hexamer/variable-number-tandem-repeat (VNTR) expansions as well as differing SVA activity for SVA subfamilies and human populations. In addition, we developed a module to annotate both reference and polymorphic SVA copies. By characterizing the landscape of both reference and polymorphic SVA retrotransposons, our study enables more accurate genotyping of these elements and facilitate the discovery of pathogenic SVA insertions.


Assuntos
Genoma Humano , Retroelementos , Humanos , Elementos Alu , Genoma Humano/genética , Repetições Minissatélites/genética , Retroelementos/genética , Elementos Nucleotídeos Curtos e Dispersos
8.
BMC Genomics ; 24(1): 400, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37460951

RESUMO

BACKGROUND: Drug resistant Mycobacterium tuberculosis prevention and care is a major challenge in Ethiopia. The World health organization has designated Ethiopia as one of the 30 high burden multi-drug resistant tuberculosis (MDR-TB) countries. There is limited information regarding genetic diversity and transmission dynamics of MDR-TB in Ethiopia. OBJECTIVE: To investigate the molecular epidemiology and transmission dynamics of MDR-TB strains using whole genome sequence (WGS) in the Amhara region. METHODS: Forty-five MDR-TB clinical isolates from Amhara region were collected between 2016 and 2018, and characterized using WGS and 24-loci Mycobacterium Interspersed Repetitive Units Variable Number of Tandem Repeats (MIRU-VNTR) typing. Clusters were defined based on the maximum distance of 12 single nucleotide polymorphisms (SNPs) or alleles as the upper threshold of genomic relatedness. Five or less SNPs or alleles distance or identical 24-loci VNTR typing is denoted as surrogate marker for recent transmission. RESULTS: Forty-one of the 45 isolates were analyzed by WGS and 44% (18/41) of the isolates were distributed into 4 clusters. Of the 41 MDR-TB isolates, 58.5% were classified as lineage 4, 36.5% lineage 3 and 5% lineage 1. Overall, TUR genotype (54%) was the predominant in MDR-TB strains. 41% (17/41) of the isolates were clustered into four WGS groups and the remaining isolates were unique strains. The predominant cluster (Cluster 1) was composed of nine isolates belonging to lineage 4 and of these, four isolates were in the recent transmission links. CONCLUSIONS: Majority of MDR-TB strain cluster and predominance of TUR lineage in the Amhara region give rise to concerns for possible ongoing transmission. Efforts to strengthen TB laboratory to advance diagnosis, intensified active case finding, and expanded contact tracing activities are needed in order to improve rapid diagnosis and initiate early treatment. This would lead to the interruption of the transmission chain and stop the spread of MDR-TB in the Amhara region.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Antituberculosos/uso terapêutico , Tuberculose/genética , Mycobacterium tuberculosis/genética , Etiópia/epidemiologia , Epidemiologia Molecular , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Genótipo , Sequenciamento Completo do Genoma , Repetições Minissatélites/genética
9.
PLoS One ; 18(5): e0285491, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37167330

RESUMO

Cassava Bacterial Blight (CBB) is a destructive disease widely distributed in the different areas where this crop is grown. Populations studies have been performed at local and national scales revealing a geographical genetic structure with temporal variations. A global epidemiology analysis of its causal agent Xanthomonas phaseoli pv. manihotis (Xpm) is needed to better understand the expansion of the disease for improving the monitoring of CBB. We targeted new tandem repeat (TR) loci with large repeat units, i.e. minisatellites, that we multiplexed in a scheme of Multi-Locus Variable number of TR Analysis (MLVA-8). This genotyping scheme separated 31 multilocus haplotypes in three clusters of single-locus variants and a singleton within a worldwide collection of 93 Xpm strains isolated over a period of fifty years. The major MLVA-8 cluster 1 grouped strains originating from all countries, except the unique Chinese strain. On the contrary, all the Xpm strains genotyped using the previously developed MLVA-14 microsatellite scheme were separated as unique haplotypes. We further propose an MLVA-12 scheme which takes advantage of combining TR loci with different mutation rates: the eight minisatellites and four faster evolving microsatellite markers, for global epidemiological surveillance. This MLVA-12 scheme identified 78 haplotypes and separated most of the strains in groups of double-locus variants (DLV) supporting some phylogenetic relationships. DLV groups were subdivided into closely related clusters of strains most often sharing the same geographical origin and isolated over a short period, supporting epidemiological relationships. The main MLVA-12 DLV group#1 was composed by strains from South America and all the African strains. The MLVA-12 scheme combining both minisatellite and microsatellite loci with different discriminatory power is expected to increase the accuracy of the phylogenetic signal and to minimize the homoplasy effects. Further investigation of the global epidemiology of Xpm will be helpful for a better control of CBB worldwide.


Assuntos
Manihot , Repetições Minissatélites , Repetições Minissatélites/genética , Manihot/genética , Filogenia , Genótipo , Repetições de Microssatélites/genética , Técnicas de Tipagem Bacteriana
10.
Sci Rep ; 13(1): 6746, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37185604

RESUMO

The objective of this study was to genotype Mycobacterium tuberculosis complex isolated from humans and cattle in northern Iran. Over the course of one year, a total of 120 human and 21 cattle isolates were tested using region of difference (RD)-based polymerase chain reaction (PCR) and mycobacterial interspersed repetitive unites-variable number tandem repeats (MIRU-VNTR). In M. tuberculosis, out of 120 isolates investigated, the most common genotype detected was NEW-1 (53.3%), followed by CAS/ Delhi (24.1%), Haarlem (5%), Beijing (4.16%), Uganda I (4.16%), S (3.3%), Ural (0.83%), TUR (0.83%), Uganda II (0.83%), Lam (0.83%) and Cameroon (0.83%). The HGDI rate was 0.9981 and the clustering rate was 10.83. Of the isolates, QUB26 had the highest allele diversity (h: 0.76), while the loci Mtub29 and MIRU24 had the lowest (h: 0). In M. Bovis, out of 123 collected tissue samples, 21 (17%) grew on culture media. The HGDI rate was 0.71 and clustering rate was 85.7%. The locus ETRC had the highest allele diversity (h: 0.45). The findings of this study suggest that there is high genetic diversity among M. tuberculosis isolates in Khorasan Razavi Province, which is consistent with similar results from other studies in other provinces in Iran and neighboring countries. This indicates that the prevalent genotypes in this study are spreading in the Middle East region. Furthermore, considering that M. Bovis isolates were identified in two clusters, it seems that all of them have a common origin and are circulating among the livestock farms in the province.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Bovinos , Animais , Mycobacterium tuberculosis/genética , Genótipo , Irã (Geográfico)/epidemiologia , Repetições Minissatélites/genética , Tuberculose/epidemiologia , Tuberculose/veterinária , Tuberculose/genética , Técnicas de Tipagem Bacteriana
11.
Neuropsychopharmacol Rep ; 43(3): 338-345, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37202909

RESUMO

BACKGROUND: One potential cause of suicide is serotonergic dysfunction. Sex differences have been reported to modulate the effects of serotonergic polymorphisms. Monoamine oxidase A (MAOA) is an enzyme that degrades serotonin and is located on the X chromosome. A previous study indicated that the upstream (u) variable number of tandem repeat (VNTR) in the MAOA gene promoter may be associated with suicide. However, a meta-analysis showed that this polymorphism may not be related to suicide. According to a recent study, compared with the uVNTR, the distal (d)VNTR and the haplotypes of the two VNTRs modulate MAOA expression. METHODS: We examined the two VNTRs in the MAOA gene promoter in 1007 subjects who committed suicide and 844 healthy controls. We analyzed the two VNTRs using fluorescence-based polymerase chain reaction assays. We conducted a meta-analysis for the two VNTRs to update it. RESULTS: Our results demonstrated that neither the genotype-based associations nor allele/haplotype frequencies of the two VNTRs were significantly associated with suicide. In the meta-analysis, we did not indicate relationships between uVNTR and suicide nor did we identify articles analyzing dVNTR in suicide. CONCLUSION: Overall, we did not find a relationship between the two VNTRs in the MAOA promoter and suicide completion; thus, warranting further studies are required.


Assuntos
Repetições Minissatélites , Suicídio , Feminino , Humanos , Masculino , Repetições Minissatélites/genética , Monoaminoxidase/genética , Polimorfismo Genético , Regiões Promotoras Genéticas
12.
Genes Genomics ; 45(7): 887-899, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37133721

RESUMO

BACKGROUND: The variable number of tandem repeat (VNTR) analyses are methods based on the detection of repeated sequences within the human genome. In order to perform DNA typing at the personal laboratory, it is necessary to improve the VNTR analysis. OBJECTIVE: The VNTR markers were difficult to popularize because PCR amplification was difficult due to its GC-rich and long nucleotide sequence. The aim of this study was to select the multiple VNTR markers that could only be identified by PCR amplification and electrophoresis. METHODS: We genotyped each of the 15 VNTR markers using genomic DNA from 260 unrelated individuals by PCR amplification. Differences in the fragment length of PCR products are visualized by agarose gel electrophoresis. To confirm their usefulness as a DNA fingerprint these 15 markers were simultaneously analyzed with the DNA of 213 individuals and verified the statistical significance. In addition, to investigate the usefulness of each of the 15 VNTR markers as paternity markers, Mendelian segregation by meiotic division within a family consisting of two or three generations was confirmed. RESULTS: Fifteen VNTR loci selected in this study could be easily amplified by PCR and analyzed by electrophoresis, and were newly named DTM1 ~ 15. The number of total alleles in each VNTR showed from 4 to 16, and 100 to 1600 bp in length, and their heterozygosity ranged from 0.2341 to 0.7915. In simultaneous analysis of 15 markers from 213 DNAs, the probability of chance appearing the same genotype in different individuals was less than 4.09E-12, indicating its usefulness as a DNA fingerprint. These loci were transmitted through meiosis by Mendelian inheritance in families. CONCLUSION: Fifteen VNTR markers have been found to be useful as DNA fingerprints for personal identification and kinship analysis that can be used at the personal laboratory level.


Assuntos
Impressões Digitais de DNA , Repetições Minissatélites , Humanos , Impressões Digitais de DNA/métodos , Repetições Minissatélites/genética , Reação em Cadeia da Polimerase , Paternidade , DNA
13.
Genome Res ; 33(4): 511-524, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37037626

RESUMO

Understanding the impact of DNA variation on human traits is a fundamental question in human genetics. Variable number tandem repeats (VNTRs) make up ∼3% of the human genome but are often excluded from association analysis owing to poor read mappability or divergent repeat content. Although methods exist to estimate VNTR length from short-read data, it is known that VNTRs vary in both length and repeat (motif) composition. Here, we use a repeat-pangenome graph (RPGG) constructed on 35 haplotype-resolved assemblies to detect variation in both VNTR length and repeat composition. We align population-scale data from the Genotype-Tissue Expression (GTEx) Consortium to examine how variations in sequence composition may be linked to expression, including cases independent of overall VNTR length. We find that 9422 out of 39,125 VNTRs are associated with nearby gene expression through motif variations, of which only 23.4% are accessible from length. Fine-mapping identifies 174 genes to be likely driven by variation in certain VNTR motifs and not overall length. We highlight two genes, CACNA1C and RNF213, that have expression associated with motif variation, showing the utility of RPGG analysis as a new approach for trait association in multiallelic and highly variable loci.


Assuntos
Adenosina Trifosfatases , Repetições Minissatélites , Humanos , Repetições Minissatélites/genética , Fenótipo , Haplótipos , Expressão Gênica , Adenosina Trifosfatases/genética , Ubiquitina-Proteína Ligases/genética
14.
PLoS One ; 18(3): e0283684, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996016

RESUMO

Enterohemorrhagic Escherichia coli O157 (O157) strains can be subdivided into clades based on their single-nucleotide polymorphisms, but such analysis using conventional methods requires intense effort by laboratories. Although multi-locus variable-number tandem repeat analysis (MLVA), which can be performed with low laboratory burden, has been used as a molecular epidemiological tool, it has not been evaluated whether MLVA can be used the clade subdivision of O157 strains like it can for that of other pathogenic bacteria. This study aimed to establish a method for subdividing O157 strains into clades using MLVA data. The standardized index of association, ISA, for O157 strains isolated in Chiba prefecture, Japan (Chiba isolates) revealed the presence of unique tandem repeat patterns in each major clade (clades 2, 3, 7, 8, and 12). A likelihood database of tandem repeats for these clades was then constructed using the Chiba isolates, and a formula for maximum a posteriori (MAP) estimation was constructed. The ratio of the number of O157 strains putatively subdivided into a clade by MAP estimation from MLVA data relative to the number of O157 strains subdivided using single-nucleotide polymorphism analysis (designated as the concordance ratio [CR]) was calculated using the Chiba isolates and O157 strains isolated in Yamagata prefecture (Yamagata isolates). The CRs for the major Chiba and Yamagata isolate clades, other than clade 2, were 89%-100%. Although the CR for clade 2 Chiba isolates was >95%, that of the Yamagata isolates was only 78.9%. However, these clade 2 CRs were not significantly different from one another, indicating that clade 2 strains can be subdivided correctly by MAP estimation. In conclusion, this study expands the utility of MLVA, previously applied predominantly for molecular epidemiological analysis, into a low-laboratory-burden tool for subdividing O157 strains into phylogenetic groups.


Assuntos
Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Escherichia coli O157 , Humanos , Escherichia coli Êntero-Hemorrágica/genética , Filogenia , Infecções por Escherichia coli/microbiologia , Repetições Minissatélites/genética , Sequências de Repetição em Tandem
15.
J Appl Microbiol ; 134(3)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36801995

RESUMO

AIMS: The ability to distinguish between Klebsiella pneumoniae strains is critical for outbreak investigations. A new typing method, intergenic region polymorphism analysis (IRPA), was developed, validated, and the discriminatory power was determined by comparison with multiple-locus variable-number tandem repeat analysis (MLVA) in this study. METHODS AND RESULTS: This method is based on the idea that every IRPA locus (polymorphic fragment of intergenic regions present in one strain but not in other strains or different fragment sizes in other strains) could divide strains into different genotypes. A 9-loci IRPA scheme was designed to type 64 K. pneumoniae isolates. Five IRPA loci were identified that conferred the same level of discrimination as the 9-loci initially examined. Among these K. pneumoniae isolates, 7.81% (5/64), 6.25% (4/64), 4.96% (3/64), 9.38% (6/64), and 1.56% (1/64) were capsular serotypes K1, K2, K5, K20, and K54, respectively. The discriminatory power of the IRPA method was better than that of MLVA expressed in Simpson's index of diversity (SI) at 0.997 and 0.988, respectively. The congruent analysis of the IRPA method and MLVA showed moderate congruence between the two methods (AR = 0.378). The AW indicated that if IRPA data are availabl, one can accurately predict the MLVA cluster. CONCLUSION: The IRPA method was found to have higher discriminatory power than MLVA and allowed for simpler band profile interpretation. The IRPA method is a rapid, simple, and high-resolution technique for molecular typing of K. pneumoniae.


Assuntos
Técnicas de Genotipagem , Klebsiella pneumoniae , Genótipo , Klebsiella pneumoniae/genética , Técnicas de Genotipagem/métodos , Tipagem Molecular/métodos , Repetições Minissatélites/genética
16.
Life Sci Alliance ; 6(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36754567

RESUMO

The dopamine transporter gene, SLC6A3, has received substantial attention in genetic association studies of various phenotypes. Although some variable number tandem repeats (VNTRs) present in SLC6A3 have been tested in genetic association studies, results have not been consistent. VNTRs in SLC6A3 that have not been examined genetically were characterized. The Tandem Repeat Annotation Library was used to characterize the VNTRs of 64 unrelated long-read haplotype-phased SLC6A3 sequences. Sequence similarity of each repeat unit of the five VNTRs is reported, along with the correlations of SNP-SNP, SNP-VNTR, and VNTR-VNTR alleles across the gene. One of these VNTRs is a novel hyper-VNTR (hyVNTR) in intron 8 of SLC6A3, which contains a range of 3.4-133.4 repeat copies and has a consensus sequence length of 38 bp, with 82% G+C content. The 38-base repeat was predicted to form G-quadruplexes in silico and was confirmed by circular dichroism spectroscopy. In addition, this hyVNTR contains multiple putative binding sites for PRDM9, which, in combination with low levels of linkage disequilibrium around the hyVNTR, suggests it might be a recombination hotspot.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina , Repetições Minissatélites , Alelos , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Haplótipos , Íntrons , Repetições Minissatélites/genética , Humanos
18.
Transbound Emerg Dis ; 69(6): 3952-3963, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36383491

RESUMO

Brucellosis is one of the most common neglected zoonotic diseases globally, with a public health significance and a high economic loss in the livestock industry caused by the bacteria of the genus Brucella. In this study, 136 Egyptian Brucella melitensis strains isolated from animals and humans between 2001 and 2020 were analysed by examining the whole-core-genome single-nucleotide polymorphism (cgSNP) in comparison to the in silico multilocus variable number of tandem repeat analysis (MLVA-16). Almost all Egyptian isolates were belonging to the West Mediterranean clade, except two isolates from buffalo and camel were belonging to the American and East Mediterranean clades, respectively. A significant correlation between the human case of brucellosis and the possible source of infection from animals was found. It seems that several outbreak strains already existing for many years have been spread over long distances and between many governorates. The cgSNP analysis, in combination with epidemiological metadata, allows a better differentiation than the MLVA-16 genotyping method and, hence, the source definition and tracking of outbreak strains. The MLVA based on the currently used 16 markers is not suitable for this task. Our results revealed 99 different cgSNP genotypes with many different outbreak strains, both older and widely distributed ones and rather newly introduced ones as well. This indicates several different incidents and sources of infections, probably by imported animals from other countries to Egypt. Comparing our panel of isolates to public databases by cgSNP analysis, the results revealed near relatives from Italy. Moreover, near relatives from the United States, France, Austria and India were found by in silico MLVA.


Assuntos
Brucella melitensis , Brucelose , Humanos , Animais , Brucella melitensis/genética , Egito/epidemiologia , Polimorfismo de Nucleotídeo Único , Tipagem de Sequências Multilocus/veterinária , Brucelose/epidemiologia , Brucelose/veterinária , Genótipo , Repetições Minissatélites/genética , Variação Genética
19.
Genes (Basel) ; 13(11)2022 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-36360164

RESUMO

Genotyping of Coxiella burnetii using multispacer sequence typing (MST) and multiple locus variable number tandem repeat analysis (MLVA) was conducted from infected animals for the first time in the Republic of Korea. C. burnetii was detected by real-time PCR, and followed by MST and MLVA genotyping. The result showed that detected C. burnetii all had the same MLVA genotype, 6-13-2-7-9-10 for markers MS23-MS24-MS27-MS28-MS33-MS34, respectively, and genotype group 61 for MST. The same genotypes were previously identified in Poland. Importantly, this MLVA type was detected in humans in France, suggesting that the Korean strain can also potentially cause Q fever in humans. MST and MLVA were very useful tools for analyzing the molecular epidemiology of C. burnetii and helpful for interpreting the epidemiological relationship between isolates from domestic and international resources.


Assuntos
Doenças dos Bovinos , Coxiella burnetii , Febre Q , Humanos , Bovinos , Animais , Coxiella burnetii/genética , Repetições Minissatélites/genética , Genótipo , Febre Q/epidemiologia , Febre Q/veterinária , Febre Q/genética , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/genética
20.
Neurosciences (Riyadh) ; 27(4): 229-236, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36252968

RESUMO

OBJECTIVE: To evaluate the relationship between patients' clinical parameters, especially clinical specifiers, and the intron 4 VNTR variant of the endothelial nitric oxide synthase (NOS3) gene in bipolar disorder (BD) patients. METHODS: A sample of 95 patients with BD and 95 healthy volunteers were included in the case-control study. The patients consecutively admitted to the outpatient psychiatry clinic for 6 months and were evaluated with some scales for clinical parameters. In addition, PCR was used to determine the NOS3 intron 4 VNTR variant. RESULTS: The NOS3 genotype and allele frequency distributions of rapid cycling BD patients were significantly different from non-rapid cycling BD patients and the control groups. Furthermore, NOS3 genotype and allele frequency distributions of treatment-resistant BD patients were significantly different from treatment-responsive BD patients and the control groups. While BD patients carrying the b/b genotype and b allele had a lower risk of rapid cycling and treatment resistance, having the b/a genotype in BD patients was at higher risk in terms of rapid cycling and treatment resistance. In addition, the number of hospitalizations and the Clinical Global Impression-Improvement Scale scores of the BD group with the b/b genotype were statistically lower than the BD group with b/a and a/a genotypes. CONCLUSIONS: We propose that the intron 4 VNTR variant of the NOS3 gene may be associated with rapid cycling and treatment resistance in Turkish patients diagnosed with BD.


Assuntos
Transtorno Bipolar , Polimorfismo Genético , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/genética , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Íntrons/genética , Repetições Minissatélites/genética , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo Genético/genética
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