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1.
Leg Med (Tokyo) ; 47: 101786, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32942206

RESUMO

In the current study, 217 unrelated individuals of the Hazara population were genotyped for 15 autosomal short tandem repeats to generate parentage and forensic efficacy parameters. Hazaras belong to the Shi'a sect and are recognized by their Turko-Mogholi features. We found that D2S1338 was the most discriminatory locus with a maximum power of exclusion and high value of polymorphism information content. Whilst the Combined Power of Discrimination (CPD), Combined Matching Probability (CMP) and Combined Power of Exclusion (CPE) were 0.999999999999999, 2.76796338879E-17 and 0.999999040733479 respectively. Furthermore, the pattern of genetic affinity with genetically assumed related populations was demonstrated through Heat Map and Phylogenetic analysis, which revealed a great level of genetic closeness of Hazaras with Mongol population and descendants of Genghis Khan. The resulting data can be used for forensic applications and anthropological studies.


Assuntos
DNA/genética , Grupos Étnicos/genética , Genética Forense , Genética Populacional , Repetições de Microssatélites/genética , Filogenia , Frequência do Gene , Humanos , Paquistão/etnologia , Polimorfismo Genético
2.
Leg Med (Tokyo) ; 47: 101788, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32950019

RESUMO

Novel Y chromosomal STR (Y-STR) markers have been continuously discovered during the past decades, promoting the widely application of Y-STRs in the area of forensic science. Here, four multicopy Y-STR markers were focused, including DYF383S1, DYF409S1, DYF411S1 and DYF371, which are rarely reported in China and differ in the number of copies on Y chromosome. Characterization of the markers was performed in population of Hunan province, China, based on sequence analysis. Allele nomenclature and allelic ladder were then developed to avoid the disunity of typing standard. To evaluate their forensic performance, gene diversity of the four loci was investigated in 548 unrelated male individuals from Hunan population. The number of haplotype was analyzed by both conservative (C-type) and expanded approach (E-type) for markers containing more than 2 copies. As detected, there were 7, 9, 13 alleles and 15, 22, 23 haplotypes for DYF383S1, DYF409S1 and DYF411S1, respectively. Thirty-two C-types and 56 E-types were found in DYF371, indicating the highest haplotype diversity (HD) among all tested loci (0.871 and 0.888 for C-type and E-type, respectively). Two other Y-STRs (DYF409S1, DYF411S1) also showed high haplotype diversity (>0.8) in the population. Combining the four loci, discrimination capacity reached 0.505 (C-type) or 0.533 (E-type), and the total HD values exceeded 0.991. The results inferred great potential of the multicopy markers to improve the resolution of paternal identification in China population.


Assuntos
Cromossomos Humanos Y/genética , Genética Forense , Genética Populacional , Repetições de Microssatélites/genética , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Feminino , Loci Gênicos/genética , Variação Genética , Haplótipos/genética , Humanos , Masculino , Paternidade
3.
Chem Biol Interact ; 331: 109226, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32971122

RESUMO

Presence of Simple Sequence Repeats (SSRs), both in genic and intergenic regions, have been widely studied in eukaryotes, prokaryotes, and viruses. In the current study, we undertook a survey to analyze the frequency and distribution of microsatellites or SSRs in multiple genomes of Coronaviridae members. We successfully identified 919 SSRs with length ≥12 bp across 55 reference genomes majority of which (838 SSRs) were found abundant in genic regions. The in-silico analysis further identified the preferential abundance of hexameric SSRs than any other size-based motif class. Our analysis shows that the genome size and GC content of the genome had a weak influence on SSR frequency and density. However, we find a positive correlation of SSRs GC content with genomic GC content. We also report relatively low abundances of all theoretically possible 501 repeat motif classes in all the genomes of Coronaviridae. The majority of SSRs were AT-rich. Overall, we see an underrepresentation of SSRs across the genomes of Coronaviridae. Besides, our integrative study highlights the presence of SSRs in ORF1ab (nsp3, nsp4, nsp5A_3CLpro and nsp5B_3CLpro, nsp6, nsp10, nsp12, nsp13, & nsp15 domains), S, ORF3a, ORF7a, N & 3' UTR regions of SARS-CoV-2 and harbours multiple mutations (3'UTR and ORF1ab SSRs serving as major mutational hotspots). This indicates the genic SSRs are under selection pressure against mutations that might alter the reading frame and at the same time responsible for rapid protein evolution. Our preliminary results indicate the significance of the limited repertoire of SSRs in the genomes of Coronaviridae.


Assuntos
Coronaviridae/genética , Repetições de Microssatélites/genética , Regiões 3' não Traduzidas , Composição de Bases , Sequência de Bases , Betacoronavirus/genética , Evolução Molecular , Genoma Viral , Humanos , Mutação , Proteínas Virais/genética
4.
PLoS One ; 15(9): e0230547, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986740

RESUMO

Hydra are freshwater polyps widely studied for their amazing regenerative capacity, adult stem cell populations, low senescence and value as ecotoxicological marker. Many wild-type strains of H. vulgaris have been collected worldwide and maintained effectively under laboratory conditions by asexual reproduction, while stable transgenic lines have been continuously produced since 2006. Efforts are now needed to ensure the genetic characterization of all these strains, which despite similar morphologies, show significant variability in their response to gene expression silencing procedures, pharmacological treatments or environmental conditions. Here, we established a rapid and reliable procedure at the single polyp level to produce via PCR amplification of three distinct microsatellite sequences molecular signatures that distinguish between Hydra strains and species. The TG-rich region of an uncharacterized gene (ms-c25145) helps to distinguish between Eurasian H. vulgaris-Pallas strains (Hm-105, Basel1, Basel2 and reg-16), between Eurasian and North American H. vulgaris strains (H. carnea, AEP), and between the H. vulgaris and H. oligactis species. The AT-rich microsatellite sequences located in the AIP gene (Aryl Hydrocarbon Receptor Interaction Protein, ms-AIP) also differ between Eurasian and North American H. vulgaris strains. Finally, the AT-rich microsatellite located in the Myb-Like cyclin D-binding transcription factor1 gene (ms-DMTF1) gene helps to distinguish certain transgenic AEP lines. This study shows that the analysis of microsatellite sequences, which is capable of tracing genomic variations between closely related lineages of Hydra, provides a sensitive and robust tool for characterizing the Hydra strains.


Assuntos
Hydra/genética , Repetições de Microssatélites/genética , Tipagem Molecular/métodos , Animais , Animais Geneticamente Modificados/genética , Modelos Animais , Reação em Cadeia da Polimerase , Polimorfismo Genético , Reprodutibilidade dos Testes
5.
PLoS One ; 15(9): e0239739, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986755

RESUMO

Rice is critical for sustainable food and nutritional security; however, nominal micronutrient quantities in grains aggravate malnutrition in rice-eating poor populations. In this study, we evaluated genetic diversity in grain iron (Fe) and zinc (Zn) contents using trait-linked simple sequence repeat (SSR) markers in the representative subset of a large collection of local and exotic rice germplasm. Results demonstrated that aromatic fine grain accessions contained relatively higher Fe and Zn contents in brown rice (BR) than coarse grain accessions and a strong positive correlation between both mineral elements. Genotyping with 24 trait-linked SSR markers identified 21 polymorphic markers, among which 17 demonstrated higher gene diversity and polymorphism information content (PIC) values, strongly indicating that markers used in current research were moderate to highly informative for evaluating the genetic diversity. Population structure, principal coordinate and phylogenetic analyses classified studied rice accessions into two fine grain specific and one fine and coarse grain admixture subpopulations. Single marker analysis recognized four ZnBR and single FeBR significant marker-trait associations (MTAs) contributing 15.41-39.72% in total observed phenotypic variance. Furthermore, high grain Fe and Zn contents linked marker alleles from significant MTAs were also identified. Collectively, these results indicate a wide genetic diversity exist in grain Fe and Zn contents of studied rice accessions and reveal perspective for marker-assisted biofortification breeding.


Assuntos
Grão Comestível/química , Grão Comestível/genética , Ferro/análise , Micronutrientes/análise , Repetições de Microssatélites/genética , Oryza/química , Oryza/genética , Polimorfismo Genético , Zinco/análise , Alelos , Biofortificação , Biomarcadores , Grão Comestível/classificação , Genes de Plantas , Genótipo , Oryza/classificação , Fenótipo , Filogenia , Melhoramento Vegetal , Locos de Características Quantitativas
6.
PLoS Med ; 17(9): e1003292, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32970670

RESUMO

BACKGROUND: Identifying stage II patients with colorectal cancer (CRC) at higher risk of progression is a clinical priority in order to optimize the advantages of adjuvant chemotherapy while avoiding unnecessary toxicity. Recently, the intensity and the quality of the host immune response in the tumor microenvironment have been reported to have an important role in tumorigenesis and an inverse association with tumor progression. This association is well established in microsatellite instable CRC. In this work, we aim to assess the usefulness of measures of T-cell infiltration as prognostic biomarkers in 640 stage II, CRC tumors, 582 of them confirmed microsatellite stable. METHODS AND FINDINGS: We measured both the quantity and clonality index of T cells by means of T-cell receptor (TCR) immunosequencing in a discovery dataset (95 patients with colon cancer diagnosed at stage II and microsatellite stable, median age 67, 30% women) and replicated the results in 3 additional series of stage II patients from 2 countries. Series 1 and 2 were recruited in Barcelona, Spain and included 112 fresh frozen (FF, median age 69, 44% women) and 163 formalin-fixed paraffin-embedded (FFPE, median age 67, 39% women) samples, respectively. Series 3 included 270 FFPE samples from patients recruited in Haifa, Northern Israel, as part of a large case-control study of CRC (median age 73, 46% women). Median follow-up time was 81.1 months. Cox regression models were fitted to evaluate the prognostic value of T-cell abundance and Simpson clonality of TCR variants adjusting by sex, age, tumor location, and stage (IIA and IIB). In the discovery dataset, higher TCR abundance was associated with better prognosis (hazard ratio [HR] for ≥Q1 = 0.25, 95% CI 0.10-0.63, P = 0.003). A functional analysis of gene expression on these tumors revealed enrichment in pathways related to immune response. Higher values of clonality index (lower diversity) were not associated with worse disease-free survival, though the HR for ≥Q3 was 2.32 (95% CI 0.90-5.97, P = 0.08). These results were replicated in an independent FF dataset (TCR abundance: HR = 0.30, 95% CI 0.12-0.72, P = 0.007; clonality: HR = 3.32, 95% CI 1.38-7.94, P = 0.007). Also, the association with prognosis was tested in 2 independent FFPE datasets. The same association was observed with TCR abundance (HR = 0.41, 95% CI 0.18-0.93, P = 0.03 and HR = 0.56, 95% CI 0.31-1, P = 0.042, respectively, for each FFPE dataset). However, the clonality index was associated with prognosis only in the FFPE dataset from Israel (HR = 2.45, 95% CI 1.39-4.32, P = 0.002). Finally, a combined analysis combining all microsatellite stable (MSS) samples demonstrated a clear prognosis value both for TCR abundance (HR = 0.39, 95% CI 0.26-0.57, P = 1.3e-06) and the clonality index (HR = 2.13, 95% CI 1.44-3.15, P = 0.0002). These associations were also observed when variables were considered continuous in the models (HR per log2 of TCR abundance = 0.85, 95% CI 0.78-0.93, P = 0.0002; HR per log2 or clonality index = 1.16, 95% CI 1.03-1.31, P = 0.016). LIMITATIONS: This is a retrospective study, and samples had been preserved with different methods. Validation series lack complete information about microsatellite instability (MSI) status and pathology assessment. The Molecular Epidemiology of Colorectal Cancer (MECC) study had information about overall survival instead of progression-free survival. CONCLUSION: Results from this study demonstrate that tumor lymphocytes, assessed by TCR repertoire quantification based on a sequencing method, are an independent prognostic factor in microsatellite stable stage II CRC.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Repetições de Microssatélites/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Estudos de Casos e Controles , Quimioterapia Adjuvante , Neoplasias Colorretais/metabolismo , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Instabilidade de Microssatélites , Repetições de Microssatélites/imunologia , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Espanha , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
7.
Nat Commun ; 11(1): 4740, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958755

RESUMO

The immune system can recognize and attack cancer cells, especially those with a high load of mutation-induced neoantigens. Such neoantigens are abundant in DNA mismatch repair (MMR)-deficient, microsatellite-unstable (MSI) cancers. MMR deficiency leads to insertion/deletion (indel) mutations at coding microsatellites (cMS) and to neoantigen-inducing translational frameshifts. Here, we develop a tool to quantify frameshift mutations in MSI colorectal and endometrial cancer. Our results show that frameshift mutation frequency is negatively correlated to the predicted immunogenicity of the resulting peptides, suggesting counterselection of cell clones with highly immunogenic frameshift peptides. This correlation is absent in tumors with Beta-2-microglobulin mutations, and HLA-A*02:01 status is related to cMS mutation patterns. Importantly, certain outlier mutations are common in MSI cancers despite being related to frameshift peptides with functionally confirmed immunogenicity, suggesting a possible driver role during MSI tumor evolution. Neoantigens resulting from shared mutations represent promising vaccine candidates for prevention of MSI cancers.


Assuntos
Mutação da Fase de Leitura , Repetições de Microssatélites/genética , Neoplasias/genética , Neoplasias/imunologia , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Antígenos HLA/genética , Humanos , Mutação INDEL , Vigilância Imunológica , Instabilidade de Microssatélites , Taxa de Mutação , Seleção Genética , Microglobulina beta-2/genética
8.
PLoS One ; 15(8): e0230404, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866150

RESUMO

High-throughput SNP genotyping has become a precondition to move to higher precision and wider genome coverage genetic analysis of natural and breeding populations of non-model species. We developed a 44,318 annotated SNP catalog for Araucaria angustifolia, a grandiose subtropical conifer tree, one of the only two native Brazilian gymnosperms, critically endangered due to its valuable wood and seeds. Following transcriptome assembly and annotation, SNPs were discovered from RNA-seq and pooled RAD-seq data. From the SNP catalog, an Axiom® SNP array with 3,038 validated SNPs was developed and used to provide a comprehensive look at the genetic diversity and structure of 15 populations across the natural range of the species. RNA-seq was a far superior source of SNPs when compared to RAD-seq in terms of conversion rate to polymorphic markers on the array, likely due to the more efficient complexity reduction of the huge conifer genome. By matching microsatellite and SNP data on the same set of A. angustifolia individuals, we show that SNPs reflect more precisely the actual genome-wide patterns of genetic diversity and structure, challenging previous microsatellite-based assessments. Moreover, SNPs corroborated the known major north-south genetic cline, but allowed a more accurate attribution to regional versus among-population differentiation, indicating the potential to select ancestry-informative markers. The availability of a public, user-friendly 3K SNP array for A. angustifolia and a catalog of 44,318 SNPs predicted to provide ~29,000 informative SNPs across ~20,000 loci across the genome, will allow tackling still unsettled questions on its evolutionary history, toward a more comprehensive picture of the origin, past dynamics and future trend of the species' genetic resources. Additionally, but not less importantly, the SNP array described, unlocks the potential to adopt genomic prediction methods to accelerate the still very timid efforts of systematic tree breeding of A. angustifolia.


Assuntos
Araucaria/genética , Brasil , Genoma de Planta/genética , Genômica/métodos , Genótipo , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único/genética , Traqueófitas/genética , Transcriptoma/genética , Árvores/genética
9.
Bull Cancer ; 107(11): 1091-1097, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980144

RESUMO

PURPOSE: This study aims to analyze sensitivities and polymorphisms of the Bethesda panel markers (BAT25, BAT26, D2S123, D5S346 and D17S250) for microsatellite instability testing in Chinese from Jiangsu Province and their clinical implication. METHODS: MSI, sensitivity and polymorphism analysis in 541 colorectal cancer (CRC) patients were detected by fragment analysis. RESULTS: Five hundred and twenty-five tissue samples and 541 blood samples of the 541 sample pairs were successfully amplified. Thirty-four (6.5%) cases were MSI-high (MSI-H) while 33 (6.3%) and 458 (87.2%) were MSI-low (MSI-L) and microsatellite stable (MSS), respectively. BAT26 (85.3%) exhibited the highest instability followed by BAT25 (82.4%), D2S123 (67.6%), D17S250 (64.7%) and D5S346 (50.0%) in MSI-H cases. The median ages of CRC patients with LS, MSI-H, MSI-L and MSS status were 38-43, 48, 60 and 63, respectively. 75.0%, 44.1%, 12.1% and 7.0% CRC cases were mucinous carcinomas in LS, MSI-H, MSI-L and MSS group, respectively. For D2S123, D17S250 and D5S346, heterozygosity was 80.8%, 74.1% and 57.7% and sizes of polymorphic variation range (PVR) were 207bp to 234bp, 140bp to 169bp and 109bp to 137bp, respectively. For D2S123 and D5S346, there was a bimodal distribution distinguishing the D17S250 from an indistinct trimodal or tetramodal distribution. CONCLUSION: MSI-H cases showed earlier onset and higher proportion of mucinous carcinomas. Mononucleotide BAT26 and BAT25 exhibited higher sensitivity than dinucleotides D2S123, D17S250 and D5S346 in the Chinese population. The dinucleotide markers were highly polymorphic with high percent of heterozygosity, great variation in repeat length and non-normal distribution in Chinese population from Jiangsu Province.


Assuntos
Adenocarcinoma Mucinoso/genética , Neoplasias Colorretais/genética , Marcadores Genéticos , Instabilidade de Microssatélites , Polimorfismo Genético , Adulto , China , Neoplasias Colorretais/etnologia , Reparo de Erro de Pareamento de DNA , Primers do DNA , Feminino , Heterozigoto , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex/métodos , Técnicas de Amplificação de Ácido Nucleico
10.
Leg Med (Tokyo) ; 47: 101760, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32739877

RESUMO

24 Y-STR loci were analyzed in 223 Altay Hui individuals and 209 Altay Kazakh individuals. Haplotype diversity (HD) and discrimination capacity (DC) values were calculated. Population pairwise genetic distances (Rst) were evaluated in AMOVA analysis and compared between two studied populations and other populations. The relationships between populations were visualized through multidimensional scaling (MDS) and neighbor-joining (NJ) tree. The results indicated higher discrimination power in the Altay Kazakh and Hui populations. The Altay Kazakh was the most distantly related to Xishuangbanna Dai, while Altay Kazakh was the most closely related to Gansu Kazakh. The results may provide useful information for paternal lineages and increase our understanding of genetic relationships between two studied populations and other populations.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Cromossomos Humanos Y/genética , Grupos Étnicos/genética , Loci Gênicos/genética , Variação Genética/genética , Genética Populacional , Repetições de Microssatélites/genética , Polimorfismo Genético , China/etnologia , Feminino , Haplótipos , Humanos , Masculino , Herança Paterna/genética
11.
Leg Med (Tokyo) ; 47: 101738, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32818903

RESUMO

Genetic markers on the Y chromosome, including short tandem repeats (Y-STRs) and single nucleotide polymorphisms (Y-SNPs), are used widely in forensic genetics. Both Y-STR-based haplotypes and Y-SNP-based haplogroups provide information on a population's genetic structure, which is useful for the identification of individuals. However, there are few studies on these two types of genetic markers in the various Chinese populations. In this study, 284 Han individuals from four prefecture-level cities in Shandong Province (Binzhou, Dezhou, Heze, and Weihai) were genotyped by 29 Y-STRs (from our previous study) and 213 Y-SNPs (self-designed for the Haplogroup O2 Y-SNP panel). Haplogroup O was the most predominant among the four cities. The highest haplogroup diversity (0.9745) was observed in the Heze population, with a discrimination capacity (DC) value of 0.5625. The haplotype diversity and DC values of the Binzhou and Heze populations were 1.0000. Furthermore, genetic differences were observed between the coastal and inland cities; the results of their statistical analysis are presented herein.


Assuntos
Cromossomos Humanos Y/genética , Grupos Étnicos/genética , Genética Populacional/métodos , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único , China/etnologia , Feminino , Genótipo , Haplótipos/genética , Humanos , Masculino
12.
PLoS One ; 15(7): e0236590, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735595

RESUMO

Zingiber montanum (Z. montanum) and Zingiber zerumbet (Z. zerumbet) are important medicinal and ornamental herbs in the genus Zingiber and family Zingiberaceae. Chloroplast-derived markers are useful for species identification and phylogenetic studies, but further development is warranted for these two Zingiber species. In this study, we report the complete chloroplast genomes of Z. montanum and Z. zerumbet, which had lengths of 164,464 bp and 163,589 bp, respectively. These genomes had typical quadripartite structures with a large single copy (LSC, 87,856-89,161 bp), a small single copy (SSC, 15,803-15,642 bp), and a pair of inverted repeats (IRa and IRb, 29,393-30,449 bp). We identified 111 unique genes in each chloroplast genome, including 79 protein-coding genes, 28 tRNAs and 4 rRNA genes. We analyzed the molecular structures, gene information, amino acid frequencies, codon usage patterns, RNA editing sites, simple sequence repeats (SSRs) and long repeats from the two chloroplast genomes. A comparison of the Z. montanum and Z. zerumbet chloroplast genomes detected 489 single-nucleotide polymorphisms (SNPs) and 172 insertions/deletions (indels). Thirteen highly divergent regions, including ycf1, rps19, rps18-rpl20, accD-psaI, psaC-ndhE, psbA-trnK-UUU, trnfM-CAU-rps14, trnE-UUC-trnT-UGU, ccsA-ndhD, psbC-trnS-UGA, start-psbA, petA-psbJ, and rbcL-accD, were identified and might be useful for future species identification and phylogeny in the genus Zingiber. Positive selection was observed for ATP synthase (atpA and atpB), RNA polymerase (rpoA), small subunit ribosomal protein (rps3) and other protein-coding genes (accD, clpP, ycf1, and ycf2) based on the Ka/Ks ratios. Additionally, chloroplast SNP-based phylogeny analyses found that Zingiber was a monophyletic sister branch to Kaempferia and that chloroplast SNPs could be used to identify Zingiber species. The genome resources in our study provide valuable information for the identification and phylogenetic analysis of the genus Zingiber and family Zingiberaceae.


Assuntos
Genoma de Cloroplastos/genética , Genômica , Filogenia , Zingiberaceae/genética , Códon/genética , Mutação INDEL , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único , Edição de RNA
13.
PLoS One ; 15(8): e0236509, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785243

RESUMO

Knowledge about population genetic structure and dispersal capabilities is important for the development of targeted management strategies for agricultural pest species. The apple fruit moth, Argyresthia conjugella (Lepidoptera, Yponomeutidae), is a pre-dispersal seed predator. Larvae feed on rowanberries (Sorbus aucuparia), and when rowanberry seed production is low (i.e., inter-masting), the moth switches from laying eggs in rowanberries to apples (Malus domestica), resulting in devastating losses in apple crops. Using genetic methods, we investigated if this small moth expresses any local genetic structure, or alternatively if gene flow may be high within the Scandinavian Peninsula (~850.000 km2, 55o - 69o N). Genetic diversity was found to be high (n = 669, mean He = 0.71). For three out of ten tetranucleotide STRs, we detected heterozygote deficiency caused by null alleles, but tests showed little impact on the overall results. Genetic differentiation between the 28 sampling locations was very low (average FST = 0.016, P < 0.000). Surprisingly, we found that all individuals could be assigned to one of two non-geographic genetic clusters, and that a third, geographic cluster was found to be associated with 30% of the sampling locations, with weak but significant signals of isolation-by-distance. Conclusively, our findings suggest wind-aided dispersal and spatial synchrony of both sexes of the apple fruit moth over large areas and across very different climatic zones. We speculate that the species may recently have had two separate genetic origins caused by a genetic bottleneck after inter-masting, followed by rapid dispersal and homogenization of the gene pool across the landscape. We suggest further investigations of spatial genetic similarities and differences of the apple fruit moth at larger geographical scales, through life-stages, across inter-masting, and during attacks by the parasitoid wasp (Microgaster politus).


Assuntos
Genética Populacional , Repetições de Microssatélites/genética , Mariposas/genética , Oviposição/fisiologia , Animais , Frutas/genética , Fluxo Gênico , Variação Genética , Larva/genética , Larva/crescimento & desenvolvimento , Malus/crescimento & desenvolvimento , Malus/parasitologia , Mariposas/patogenicidade , Mariposas/fisiologia , Oviposição/genética , Dispersão de Sementes/genética , Sorbus/genética , Sorbus/parasitologia
14.
PLoS One ; 15(8): e0236351, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785293

RESUMO

Hybrid performance during wheat breeding can be improved by analyzing genetic distance (GD) among wheat genotypes and determining its correlation with heterosis. This study evaluated the GD between 16 wheat genotypes by using 60 simple sequence repeat (SSR) markers to classify them according to their relationships and select those with greater genetic diversity, evaluate the correlation of the SSR marker distance with heterotic performance and specific combining ability (SCA) for heat stress tolerance, and identify traits that most influence grain yield (GY). Eight parental genotypes with greater genetic diversity and their 28 F1 hybrids generated using diallel crossing were evaluated for 12 measured traits in two seasons. The GD varied from 0.235 to 0.911 across the 16 genotypes. Cluster analysis based on the GD estimated using SSRs classified the genotypes into three major groups and six sub-groups, almost consistent with the results of principal coordinate analysis. The combined data indicated that five hybrids showed 20% greater yield than mid-parent or better-parent. Two hybrids (P2 × P4) and (P2 × P5), which showed the highest performance of days to heading (DH), grain filling duration (GFD), and GY, and had large genetic diversity among themselves (0.883 and 0.911, respectively), were deemed as promising heat-tolerant hybrids. They showed the best mid-parent heterosis and better-parent heterosis (BPH) for DH (-11.57 and -7.65%; -13.39 and -8.36%, respectively), GFD (12.74 and 12.17%; 12.09 and 10.59%, respectively), and GY (36.04 and 20.04%; 44.06 and 37.73%, respectively). Correlation between GD and each of BPH and SCA effects based on SSR markers was significantly positive for GFD, hundred kernel weight, number of kernels per spike, harvest index, GY, and grain filling rate and was significantly negative for DH. These correlations indicate that the performance of wheat hybrids with high GY and earliness could be predicted by determining the GD of the parents by using SSR markers. Multivariate analysis (stepwise regression and path coefficient) suggested that GFD, hundred kernel weight, days to maturity, and number of kernels per spike had the highest influence on GY.


Assuntos
Resposta ao Choque Térmico/genética , Vigor Híbrido/genética , Seleção Genética/genética , Triticum/genética , Pão , Cruzamento , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Genótipo , Humanos , Hibridização Genética/genética , Repetições de Microssatélites/genética , Fenótipo , Triticum/crescimento & desenvolvimento
15.
BMC Evol Biol ; 20(1): 96, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736519

RESUMO

BACKGROUND: Chloroplast genome sequence data is very useful in studying/addressing the phylogeny of plants at various taxonomic ranks. However, there are no empirical observations on the patterns, directions, and mutation rates, which are the key topics in chloroplast genome evolution. In this study, we used Calycanthaceae as a model to investigate the evolutionary patterns, directions and rates of both nucleotide substitutions and structural mutations at different taxonomic ranks. RESULTS: There were 2861 polymorphic nucleotide sites on the five chloroplast genomes, and 98% of polymorphic sites were biallelic. There was a single-nucleotide substitution bias in chloroplast genomes. A â†’ T or T â†’ A (2.84%) and G â†’ C or C â†’ G (3.65%) were found to occur significantly less frequently than the other four transversion mutation types. Synonymous mutations kept balanced pace with nonsynonymous mutations, whereas biased directions appeared between transition and transversion mutations and among transversion mutations. Of the structural mutations, indels and repeats had obvious directions, but microsatellites and inversions were non-directional. Structural mutations increased the single nucleotide mutations rates. The mutation rates per site per year were estimated to be 0.14-0.34 × 10- 9 for nucleotide substitution at different taxonomic ranks, 0.64 × 10- 11 for indels and 1.0 × 10- 11 for repeats. CONCLUSIONS: Our direct counts of chloroplast genome evolution events provide raw data for correctly modeling the evolution of sequence data for phylogenetic inferences.


Assuntos
Calycanthaceae/genética , Evolução Molecular , Genoma de Cloroplastos , Mutação/genética , Nucleotídeos/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Sequência de Bases , Cloroplastos/genética , Inversão Cromossômica/genética , Loci Gênicos , Mutação INDEL/genética , Repetições de Microssatélites/genética , Taxa de Mutação , Filogenia , Especificidade da Espécie
16.
PLoS One ; 15(8): e0237765, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804960

RESUMO

The failure of the maternal immune system to recognize fetal antigens and vice versa due to MHC similarity between the foal and its dam might result in the lack of placental separation during parturition in mares. The aim of the study was to investigate the influence of MHC similarity between a mare and a foal on the incidence of retained fetal membranes (RFM) in post-partum mares. DNA was sampled from 43 draft mares and their foals. Mares which failed to expel fetal membranes within three hours after foal expulsion were considered the RFM group (n = 14) and mares that expelled fetal membranes during the above period were the control group (n = 29). Nine MHC microsatellites of MHC I and MHC II were amplified for all mares and foals. MHC compatibility and MHC genetic similarity between mares and their foals was determined based on MHC microsatellites. The inbreeding coefficient was also calculated for all horses. The incidence of RFM in the studied population was 33%. Compatibility in MHC I and MHC II did not increase the risk of RFM in the studied population of draft mares (P>0.05). Differences in MHC similarity at the genetic level were not observed between mare-foal pairs in RFM and control group (P>0.05). We suspect that RFM in draft mares may not be associated with MHC similarity between a foal and its dam. Despite the above, draft horses could be genetically predisposed to the disease.


Assuntos
Doenças dos Cavalos/imunologia , Cavalos/imunologia , Endogamia , Complexo Principal de Histocompatibilidade/imunologia , Placenta Retida/veterinária , Animais , Estudos Transversais , Feminino , Técnicas de Genotipagem , Doenças dos Cavalos/epidemiologia , Cavalos/genética , Incidência , Complexo Principal de Histocompatibilidade/genética , Repetições de Microssatélites/genética , Repetições de Microssatélites/imunologia , Placenta Retida/epidemiologia , Placenta Retida/imunologia , Período Pós-Parto , Gravidez
17.
Parasitol Res ; 119(9): 2829-2835, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32705375

RESUMO

Cephenemyia stimulator and Oestrus ovis are two important parasitic bot flies (Oestridae) species causing myiasis, with a potential negative impact on the welfare of the host. Using next-generation sequencing approach and bioinformatics tools, a large panel of possible microsatellites loci was obtained in both species. Primer pairs were designed for 15 selected microsatellite loci in C. stimulator and other 15 loci in O. ovis for PCR amplification. Loci amplification and analysis were performed in four populations of each species. The results demonstrated that all selected loci were polymorphic, with the number of alleles ranging from 2 to 6 per locus in C. stimulator and 3 to 13 per locus in O. ovis. This is the first time to describe these microsatellite loci for C. stimulator and O. ovis. These two sets of microsatellite markers could be further used for biogeographic and population genetics studies.


Assuntos
Dípteros/genética , Repetições de Microssatélites/genética , Alelos , Animais , Dípteros/classificação , Genética Populacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Miíase/parasitologia , Reação em Cadeia da Polimerase , Ovinos
18.
BMC Med Genet ; 21(1): 141, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611331

RESUMO

BACKGROUND: Lynch syndrome (LS), which is known as a hereditary cancer syndrome, is distinguished by microsatellite instability, represented by the altered number of repetitive sequences in the coding and/or non-coding region. Immunohistochemical staining (IHC) of DNA mismatch repair (MMR) proteins (e.g., MLH1, MSH2, MSH6, and PMS2) has been recognized as an useful technique for screening of LS. Previous study has shown that the assessment of IHC, however, requires specific caution due to variable staining patterns even without germline mutations in MMR genes. CASE PRESENTATION: A 48-year-old man, who had been treated for anaplastic astrocytoma, was referred to our department for the precise examination of progressing anemia. Whole-body examination revealed two advanced carcinomas in descending colon and stomach. A hypo-vascular mass lesion was detected in liver as well. Pathological diagnosis (on surgical specimens) was poorly differentiated adenocarcinoma in descending colon, moderately differentiated tubular adenocarcinoma in stomach, and liver metastasis, which is possibly from colon. It was suspected that this case would be Turcot's syndrome-type-1 due to its specific family history having two cases of colon cancer within the second relatives. Pathogenic frameshift mutations in codon 618 of MLH1 gene was identified. Immunohistochemical analyses (IHC) demonstrated complete loss of MLH1 immuno-expression as well as of PMS2 except for those in brain tumor. Although frameshift mutation was not found in MSH6 gene, histological expression of MSH6 was patchy in primary colon carcinoma and was completely lost in the metastatic site in liver. MSH6 expression in gastric carcinoma, a coincidental cancer in this case, was intact. An abnormal (C)8 region was identified by the cloned PCR of colon and liver tumors but not from gastric cancer. Frameshift mutation in a (C)8 tract in exon 5 of the MSH6 gene was also detected in liver metastasis. CONCLUSION: This case supports a plausible mechanism, proposed by a previous literature, for the reduced expression of MSH6 in a somatic mutation manner, which might preferentially happen in colon cancer rather than in stomach carcinoma in MLH1/PMS2-deficient type of Turcot's syndrome type 1.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias do Colo/genética , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/imunologia , Predisposição Genética para Doença , Neoplasias Hepáticas/secundário , Mutação/genética , Síndromes Neoplásicas Hereditárias/genética , Adulto , Sequência de Bases , Reparo de Erro de Pareamento de DNA/genética , Feminino , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Linhagem
19.
PLoS One ; 15(7): e0235354, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609773

RESUMO

The Chinese chestnut (Castanea mollissima Bl.) was introduced into Japan about 100 years ago. Since then, a number of Chinese chestnut cultivars and Japanese-Chinese hybrid cultivars have been selected by farmers and plant breeders, but little information has been available about their origins and genetic relationships. A classification based on simple sequence repeat markers was conducted using 230 cultivars including Japanese chestnut (Castanea crenata Sieb. et Zucc.) cultivars originated in Japan, Japanese-Chinese hybrid cultivars, and Chinese chestnut cultivars originated in both Japan and China. First, a search for synonyms (cultivars with identical genotypes) revealed 23 synonym groups among the Chinese chestnut cultivars, and all but one cultivar from each synonym group was omitted from further analyses. Second, genetic structure analysis showed a clear division between Japanese and Chinese chestnut, and most of the Japanese and Chinese cultivars had a simple genetic structure corresponding to the expected species. On the other hand, most Japanese-Chinese hybrid cultivars had admixed genetic structure. Through a combination of parentage and chloroplast haplotype analyses, 16 of the 18 hybrid cultivars in this study were inferred to have parent-offspring relationships with other cultivars originated in Japan. Finally, Bayesian clustering and chloroplast haplotype analysis showed that the 116 Chinese chestnut cultivars could be divided into two groups: one originated in the Hebei region of China and the other originated in the Jiangsu and Anhui regions of China. The Chinese chestnut cultivars selected in Japan showed various patterns of genetic structure including Hebei origin, Jiangsu or Anhui origin, and admixed. The chestnut cultivar genetic classifications obtained in this study will be useful for both Japanese and Chinese chestnut breeding programs.


Assuntos
Cloroplastos/genética , Fagaceae/classificação , Fagaceae/genética , Repetições de Microssatélites/genética , China , Deriva Genética , Genótipo , Japão , Filogenia , Melhoramento Vegetal
20.
Proc Natl Acad Sci U S A ; 117(31): 18591-18599, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690681

RESUMO

Repeat associated non-AUG (RAN) translation is found in a growing number of microsatellite expansion diseases, but the mechanisms remain unclear. We show that RAN translation is highly regulated by the double-stranded RNA-dependent protein kinase (PKR). In cells, structured CAG, CCUG, CAGG, and G4C2 expansion RNAs activate PKR, which leads to increased levels of multiple RAN proteins. Blocking PKR using PKR-K296R, the TAR RNA binding protein or PKR-KO cells, reduces RAN protein levels. p-PKR is elevated in C9orf72 ALS/FTD human and mouse brains, and inhibiting PKR in C9orf72 BAC transgenic mice using AAV-PKR-K296R or the Food and Drug Administration (FDA)-approved drug metformin, decreases RAN proteins, and improves behavior and pathology. In summary, targeting PKR, including by use of metformin, is a promising therapeutic approach for C9orf72 ALS/FTD and other expansion diseases.


Assuntos
Esclerose Amiotrófica Lateral/metabolismo , Proteína C9orf72 , Metformina/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , eIF-2 Quinase , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Modelos Animais de Doenças , Demência Frontotemporal/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Repetições de Microssatélites/genética , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
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