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1.
PLoS One ; 18(11): e0292611, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37943872

RESUMO

Esophageal squamous cell carcinoma (ESCC) has a very high incidence rate in northeastern Iran. Our team previously reported the BReast CAncer gene 2 (BRCA2) p.K3326* mutation as a moderately penetrant ESCC susceptibility variant in northern Iran (odds ratio (OR) = 3.64, 95% confidence interval (CI) = 1.74-7.59, P = 0.0003). Recently, it has been reported that aldehydes can induce BRCA2 haploinsufficiency in cells with a heterozygous pathogenic BRCA2 mutation and predispose them to carcinogenic effects. Based on this observation, we speculate that dysfunctional variants in Aldehyde Dehydrogenase 2 Family Member (ALDH2) may result in aldehyde-induced BRCA2 haploinsufficiency and increase cancer risk in BRCA2 mutation carriers. In support of this hypothesis, our team recently reported the breast cancer risk modifying effect of an ALDH2 common polymorphism, rs10744777, among Polish carriers of the BRCA2 p.K3326* mutation. In the current case-control study, we aimed to investigate the ESCC risk modifying effect of this ALDH2 polymorphism among BRCA2 p.K3326* mutation carriers. We assessed the interaction between the ALDH2 rs10744777 polymorphism and BRCA2 p.K3326* mutation in ESCC risk by genotyping this ALDH2 variant in the germline DNA of 746 ESCC cases and 1,373 controls from northern Iran who were previously genotyped for the BRCA2 p.K3326* mutation. Among a total of 464 individuals with TT genotype of the ALDH2 rs10744777 polymorphism, which is associated with lower ALDH2 expression, we found 9 of 164 cases versus 3 of 300 controls who carried the BRCA2 p.K3326* variant (OR = 5.66, 95% CI = 1.22-26.2, P = 0.018). This finding supports our hypothesis that the ALDH2-rs10744777 TT genotype may be a significant risk modifier of ESCC in individuals with a BRCA2 p.K3326* mutation.


Assuntos
Neoplasias da Mama , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Feminino , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/complicações , Polimorfismo de Nucleotídeo Único , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Estudos de Casos e Controles , Predisposição Genética para Doença , Fatores de Risco , Aldeído-Desidrogenase Mitocondrial/genética , Genótipo , Neoplasias da Mama/complicações , Proteína BRCA2/genética
2.
Am J Hum Genet ; 110(4): 648-662, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36977412

RESUMO

Several breast cancer susceptibility genes have been discovered, but more are likely to exist. To identify additional breast cancer susceptibility genes, we used the founder population of Poland and performed whole-exome sequencing on 510 women with familial breast cancer and 308 control subjects. We identified a rare mutation in ATRIP (GenBank: NM_130384.3: c.1152_1155del [p.Gly385Ter]) in two women with breast cancer. At the validation phase, we found this variant in 42/16,085 unselected Polish breast cancer-affected individuals and in 11/9,285 control subjects (OR = 2.14, 95% CI = 1.13-4.28, p = 0.02). By analyzing the sequence data of the UK Biobank study participants (450,000 individuals), we identified ATRIP loss-of-function variants among 13/15,643 breast cancer-affected individuals versus 40/157,943 control subjects (OR = 3.28, 95% CI = 1.76-6.14, p < 0.001). Immunohistochemistry and functional studies showed the ATRIP c.1152_1155del variant allele is weakly expressed compared to the wild-type allele, and truncated ATRIP fails to perform its normal function to prevent replicative stress. We showed that tumors of women with breast cancer who have a germline ATRIP mutation have loss of heterozygosity at the site of ATRIP mutation and genomic homologous recombination deficiency. ATRIP is a critical partner of ATR that binds to RPA coating single-stranded DNA at sites of stalled DNA replication forks. Proper activation of ATR-ATRIP elicits a DNA damage checkpoint crucial in regulating cellular responses to DNA replication stress. Based on our observations, we conclude ATRIP is a breast cancer susceptibility gene candidate linking DNA replication stress to breast cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Neoplasias da Mama , Proteínas de Ligação a DNA , Feminino , Humanos , Proteínas Adaptadoras de Transdução de Sinal/genética , Bancos de Espécimes Biológicos , Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Dano ao DNA , Proteínas de Ligação a DNA/genética , Polônia/epidemiologia , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Reino Unido/epidemiologia
3.
Cancer Med ; 12(6): 7580-7587, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36544278

RESUMO

BACKGROUND: Knowledge of pathogenic variants in cancer-predisposing genes is important when making breast cancer treatment decisions, but genetic testing is not universal and criteria must be met to qualify for genetic testing. The objective of this study was to evaluate the pathogenic variant yield for nine cancer predisposition genes by testing criteria, singly and in combination. METHODS: Women diagnosed with breast cancer between June 2013 and May 2018 were recruited from four centers in Toronto, Canada. Participants completed a demographics and family history questionnaire and clinical characteristics were collected from medical charts. Genetic testing was done for BRCA1, BRCA2, PALB2, ATM, CHEK2, BRIP1, RAD51D, RECQL, and TP53. Pathogenic variant frequencies were calculated according to five criteria (age ≤ 50, triple-negative breast cancer, family history, bilateral breast cancer, or Jewish ethnicity). RESULTS: Of the 1006 women studied, 100 women (9.9%) were found to have a pathogenic variant in one of the nine genes tested. The highest prevalence of pathogenic variants was found in women with triple-negative breast cancer (23%). Of the 100 pathogenic variants detected, 78 were detected in women diagnosed at age 50 or less. A total of 96% of the mutations were identified with three criteria (age of diagnosis, family history, and triple-negative status). CONCLUSIONS: Genetic testing criteria for women with breast cancer should include women with triple-negative breast cancer, regardless of age. All women aged 50 years or below at time of breast cancer diagnosis should be offered genetic testing.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/epidemiologia , Neoplasias de Mama Triplo Negativas/genética , Predisposição Genética para Doença , RecQ Helicases/genética , Testes Genéticos , Mutação , Mutação em Linhagem Germinativa
4.
Arch Microbiol ; 204(10): 624, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36112329

RESUMO

The present study aimed to evaluate the effects of new Lactobacillus plantarum strain isolated from dairy products as well as chitosan nanoparticles on reducing aflatoxin B1 (AFB1) toxicity In vitro. After collection and preparation of yogurt, cheese, milk, and whey products, lactic acid bacteria (LABs) were isolated and identified using biochemical and molecular methods. pH, bile, and salt tolerance tests were used to measure probiotic activity. Then, the antimicrobial activity of LABs against gastrointestinal pathogens was studied. The strain isolated from cheese (C1) was selected as the appropriate strain and antibiotic susceptibility test was performed for this strain. Then, the effect of C1 isolate and chitosan nanoparticles on reducing aflatoxin B1 (AFB1) in the medium was studied by measuring AFB1 using the enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC). The results of biochemical evaluations indicated the separation of different strains of L. plantarum. Antimicrobial activity test showed extensive antimicrobial activity of C1 isolate. The results showed that this strain has good probiotic activities. This strain was shown to be resistant to erythromycin, fusidic acid, gentamicin, kanamycin, nalidixic acid, neomycin, ofloxacin, and vancomycin antibiotics. C1 strain together with chitosan nanoparticles was able to reduce AFB1 in the medium and, when both were used simultaneously, a synergistic effect was seen in reducing AFB1 from the medium. Based on the findings, it can be concluded that the new C1 L. plantarum strains together with chitosan nanoparticles had synergistic effects on reducing AFB1 toxin in food products.


Assuntos
Quitosana , Lactobacillales , Lactobacillus plantarum , Probióticos , Aflatoxina B1 , Antibacterianos/farmacologia , Quitosana/farmacologia , Eritromicina , Ácido Fusídico , Gentamicinas , Canamicina , Ácido Nalidíxico , Neomicina , Ofloxacino , Probióticos/farmacologia , Vancomicina
5.
Br J Cancer ; 127(5): 879-885, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35710751

RESUMO

BACKGROUND: Several clinical and tumour factors impact on ovarian cancer survival. It is important to evaluate if germline mutations impact long-term outcomes among patients with epithelial ovarian cancer. METHODS: We followed 1422 Ontario women with ovarian cancer. Clinical information was obtained from medical records and vital status was determined by registry linkage. Germline genetic testing was performed for 12 susceptibility genes. We estimated 20-year cancer-specific survival according to various factors. RESULTS: Twenty-year survival was inferior for women with serous cancers vs. other types (22.3% vs. 68.6%; P < 0.0001). Of the 1422 patients, 248 (17.4%) carried a germline mutation; 119 BRCA1; 75 BRCA2; 7 in a mismatch repair (MMR) gene and 47 in one of seven other genes. Among serous patients, 20-year survival was 28.9% for similar for women with a BRCA1 (28.9%), BRCA2 (21.2%) or no mutation (21.6%). Among endometrioid patients, 20-year survival was poor for women with a BRCA vs. no mutation (47.3% vs. 70.4%; P = 0.004). Six of the seven MMR mutation carriers are currently alive, while all three PALB2 mutation carriers died within 3 years of diagnosis. Among women with Stage III/IV serous cancers, 20-year survival was 9.4% for those with vs. 46.5% for those with no residual disease (HR = 2.91; 95% CI 2.12-4.09, P < 0.0001). CONCLUSIONS: The most important predictor of long-term survival was no residual disease post surgery. BRCA mutation status was not predictive of long-term survival while those with MMR mutations had excellent survival. Larger studies on PALB2 carriers are needed.


Assuntos
Carcinoma Epitelial do Ovário , Mutação em Linhagem Germinativa , Proteína BRCA2/genética , Carcinoma Epitelial do Ovário/genética , Feminino , Genes BRCA1 , Genes BRCA2 , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Prognóstico
6.
JCO Precis Oncol ; 6: e2100450, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35442721

RESUMO

PURPOSE: The BRCA2 p.K3326* variant is considered a low-penetrance variant for breast cancer. Aldehydes that accumulate in cells under insufficient aldehyde oxidation were most recently shown to trigger carcinogenesis by promoting depletion of BRCA2 protein. Allele T of the common variant rs10744777 in the ALDH2 gene was associated with reduced expression of aldehyde dehydrogenase, the main enzyme in aldehyde oxidation. We hypothesized that this allele could modify breast cancer risk in women with the BRCA2 p.K3326* low-penetrance variant through reduced function of ALDH2, increased accumulation of cellular aldehydes, and depletion of BRCA2 protein. MATERIALS AND METHODS: We genotyped 11,873 Polish women diagnosed with breast cancer and 7,615 ethnically matched controls for these two variants. Next, we extended our analysis of rs10744777 to 231 carriers of pathogenic BRCA2 mutations. RESULTS: BRCA2 p.K3326* variant was associated with significant increase in breast cancer risk only in those who were homozygous for the T allele of the ALDH2 rs10744777 variant (odds ratio = 1.72; 95% CI, 1.19 to 2.48; P = .003). The BRCA2 p.K3326* variant did not increase the risk of breast cancer among those who were heterozygous or homozygous for the C allele of the ALDH2 rs10744777 variant (odds ratio = 1.05; 95% CI, 0.73 to 1.51; P = .81). In the carriers of high-risk BRCA2 mutations, the TT genotype of rs10744777 conferred a modest (18%) and not significant increase in breast cancer risk. CONCLUSION: Our results suggest that BRCA2 p.K3326* variant, which is low-penetrance by itself, confers increased breast cancer risk on the background of the TT genotype of the ALDH2 rs10744777 variant in the Polish population.


Assuntos
Proteína BRCA2 , Neoplasias da Mama , Aldeído-Desidrogenase Mitocondrial/genética , Aldeídos , Proteína BRCA2/genética , Neoplasias da Mama/epidemiologia , Feminino , Predisposição Genética para Doença/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética
7.
Immunol Lett ; 223: 97-105, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32360304

RESUMO

BACKGROUND: Ankylosing spondylitis (AS) is a chronic autoimmune disease, in which genetic polymorphisms are critically important in establishing inflammatory state. Endoplasmic reticulum aminopeptidase (ERAP) 2 gene has been implied to be involved in AS etiopathogenesis. The current study evaluated the association of ERAP2 gene single nucleotide polymorphisms (SNPs) with susceptibility to AS in an Iranian population. METHODS: Two hundred and forty AS patients and 240 healthy individuals were recruited. DNA extraction was performed from whole blood samples and RNA content was isolated from peripheral blood mononuclear cells (PBMCs). Real-time allelic discrimination approach was exerted to genotype all subjects for rs2910686, rs2248374, and rs2549782 SNPs. After cDNA synthesis, mRNA expression of cytokines was determined. Enzyme-linked immunosorbent assay (ELISA) was exerted to evaluate the cytokine levels in serum of participants. RESULTS: None of the SNPs were associated with AS risk in the whole population. However, allele and heterozygote genotype of rs2910686 SNP were associated significantly with higher risk of AS in Human leukocyte antigen (HLA)-B27 positive group. mRNA expression and serum concentrations of interleukin (IL)-17A, IL-23, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α was increased in AS patients compared with controls. Nonetheless, mRNA expression and serum levels of cytokines was not significantly different among HLA-B27 positive AS patients with different three genotypes for rs2910686 SNP. CONCLUSIONS: AlthoughERAP2 gene rs2910686 polymorphism was significantly associated with increased risk of AS susceptibility, it might not be involved in regulation of the inflammatory cytokines during AS pathogenesis.


Assuntos
Aminopeptidases/genética , Genótipo , Espondilite Anquilosante/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Antígeno HLA-B27/genética , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
9.
BMC Genomics ; 19(1): 964, 2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30587115

RESUMO

BACKGROUND: Studies that aim at explaining phenotypes or disease susceptibility by genetic or epigenetic variants often rely on clustering methods to stratify individuals or samples. While statistical associations may point at increased risk for certain parts of the population, the ultimate goal is to make precise predictions for each individual. This necessitates tools that allow for the rapid inspection of each data point, in particular to find explanations for outliers. RESULTS: ACES is an integrative cluster- and phenotype-browser, which implements standard clustering methods, as well as multiple visualization methods in which all sample information can be displayed quickly. In addition, ACES can automatically mine a list of phenotypes for cluster enrichment, whereby the number of clusters and their boundaries are estimated by a novel method. For visual data browsing, ACES provides a 2D or 3D PCA or Heat Map view. ACES is implemented in Java, with a focus on a user-friendly, interactive, graphical interface. CONCLUSIONS: ACES has been proven an invaluable tool for analyzing large, pre-filtered DNA methylation data sets and RNA-Sequencing data, due to its ease to link molecular markers to complex phenotypes. The source code is available from https://github.com/GrabherrGroup/ACES .


Assuntos
Interface Usuário-Computador , Análise por Conglomerados , Metilação de DNA , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Humanos , Acesso à Internet , Análise de Componente Principal , RNA/química , RNA/metabolismo
10.
Proc Natl Acad Sci U S A ; 115(46): E10970-E10978, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30373829

RESUMO

The Populus genus is one of the major plant model systems, but genomic resources have thus far primarily been available for poplar species, and primarily Populus trichocarpa (Torr. & Gray), which was the first tree with a whole-genome assembly. To further advance evolutionary and functional genomic analyses in Populus, we produced genome assemblies and population genetics resources of two aspen species, Populus tremula L. and Populus tremuloides Michx. The two aspen species have distributions spanning the Northern Hemisphere, where they are keystone species supporting a wide variety of dependent communities and produce a diverse array of secondary metabolites. Our analyses show that the two aspens share a similar genome structure and a highly conserved gene content with P. trichocarpa but display substantially higher levels of heterozygosity. Based on population resequencing data, we observed widespread positive and negative selection acting on both coding and noncoding regions. Furthermore, patterns of genetic diversity and molecular evolution in aspen are influenced by a number of features, such as expression level, coexpression network connectivity, and regulatory variation. To maximize the community utility of these resources, we have integrated all presented data within the PopGenIE web resource (PopGenIE.org).


Assuntos
Populus/genética , Evolução Biológica , DNA de Plantas/genética , Evolução Molecular , Variação Genética , Genética Populacional/métodos , Genoma de Planta , Genômica , Desequilíbrio de Ligação/genética , Filogenia , Seleção Genética/genética , Análise de Sequência de DNA/métodos , Árvores/genética
11.
Nat Commun ; 8(1): 2286, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29273779

RESUMO

Salamanders exhibit an extraordinary ability among vertebrates to regenerate complex body parts. However, scarce genomic resources have limited our understanding of regeneration in adult salamanders. Here, we present the ~20 Gb genome and transcriptome of the Iberian ribbed newt Pleurodeles waltl, a tractable species suitable for laboratory research. We find that embryonic stem cell-specific miRNAs mir-93b and mir-427/430/302, as well as Harbinger DNA transposons carrying the Myb-like proto-oncogene have expanded dramatically in the Pleurodeles waltl genome and are co-expressed during limb regeneration. Moreover, we find that a family of salamander methyltransferases is expressed specifically in adult appendages. Using CRISPR/Cas9 technology to perturb transcription factors, we demonstrate that, unlike the axolotl, Pax3 is present and necessary for development and that contrary to mammals, muscle regeneration is normal without functional Pax7 gene. Our data provide a foundation for comparative genomic studies that generate models for the uneven distribution of regenerative capacities among vertebrates.


Assuntos
Extremidades/fisiologia , Genoma/genética , MicroRNAs/genética , Pleurodeles/genética , Regeneração/genética , Ambystoma mexicanum/genética , Animais , Sistemas CRISPR-Cas , Elementos de DNA Transponíveis/genética , Células-Tronco Embrionárias/metabolismo , Edição de Genes , Perfilação da Expressão Gênica , Genômica , Músculo Esquelético/fisiologia , Fator de Transcrição PAX3/genética , Fator de Transcrição PAX7/genética , Proto-Oncogenes/genética , Regeneração/fisiologia
12.
BMC Genomics ; 18(1): 571, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28768481

RESUMO

BACKGROUND: DNA methylation is a major mechanism involved in the epigenetic state of a cell. It has been observed that the methylation status of certain CpG sites close to or within a gene can directly affect its expression, either by silencing or, in some cases, up-regulating transcription. However, a vertebrate genome contains millions of CpG sites, all of which are potential targets for methylation, and the specific effects of most sites have not been characterized to date. To study the complex interplay between methylation status, cellular programs, and the resulting phenotypes, we present PiiL, an interactive gene expression pathway browser, facilitating analyses through an integrated view of methylation and expression on multiple levels. RESULTS: PiiL allows for specific hypothesis testing by quickly assessing pathways or gene networks, where the data is projected onto pathways that can be downloaded directly from the online KEGG database. PiiL provides a comprehensive set of analysis features that allow for quick and specific pattern searches. Individual CpG sites and their impact on host gene expression, as well as the impact on other genes present in the regulatory network, can be examined. To exemplify the power of this approach, we analyzed two types of brain tumors, Glioblastoma multiform and lower grade gliomas. CONCLUSION: At a glance, we could confirm earlier findings that the predominant methylation and expression patterns separate perfectly by mutations in the IDH genes, rather than by histology. We could also infer the IDH mutation status for samples for which the genotype was not known. By applying different filtering methods, we show that a subset of CpG sites exhibits consistent methylation patterns, and that the status of sites affect the expression of key regulator genes, as well as other genes located downstream in the same pathways. PiiL is implemented in Java with focus on a user-friendly graphical interface. The source code is available under the GPL license from https://github.com/behroozt/PiiL.git .


Assuntos
Metilação de DNA , Perfilação da Expressão Gênica , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Ilhas de CpG/genética , Bases de Dados Genéticas , Redes Reguladoras de Genes , Glioblastoma/genética , Glioblastoma/patologia
13.
Med J Islam Repub Iran ; 30: 339, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27390709

RESUMO

BACKGROUND: The present study aims to evaluate the cost-effectiveness of Dynamic Interspinous Spacer (Coflex®) and Static Spacer (X-STOP ®) compared to Laminectomy (LAMI) in patients with lumbar spinal stenosis. METHODS: A decision-analysis model was developed to estimate the cost-effectiveness. The effectiveness parameters were obtained from a systematic literature review in relevant databases including PUBMED and EMBASE. A meta-analysis was performed using the STATA statistical package and a random model was used to collect measures of mean difference of visual analogue scale (VAS) pain score before and after intervention in X-stop, Coflex and LAMI (95% confidence intervals). Cost data were obtained from provider and associated literature based on health care provider prospective. We assumed that the probability of the success rate of surgery in each intervention from associated literature and calculated Incremental cost effectiveness ratio. A one-way sensitivity analysis was also carried out. RESULTS: Twenty-four out of 294 studies are included in the Meta-analysis. The overall pooled estimate of the mean difference of VAS pain score were 3.49 (95% CI 3.7-4.2) and 4.14 (95% CI 3.09- 5.19) for X-stop and Coflex, respectively. In addition, we assumed the overall pooled estimate of 5.3 (95% CI 2.15-7.4) on the basis of literature for LAMI. The average cost per LAMI surgery, X-stop and Coflex was US$ 3019, US$ 2022 and US$ 2566, respectively. Incremental cost effectiveness ratio of X-stop and Coflex versus LAMI was US$ 665.9 and US$ 780.7, respectively. CONCLUSION: Static Interspinous Spacer (X-stop) appears to be the most cost-effective treatment strategy in base case scenario with success rate of LAMI (range between (55%-70%). A sensitivity analysis shows that the increase probability of success rate of LAMI was more than 70 % and less than 55% which lead to the cost effectiveness of the Coflex intervention.

14.
PLoS One ; 10(9): e0139080, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26413905

RESUMO

After performing de novo transcript assembly of >1 billion RNA-Sequencing reads obtained from 22 samples of different Norway spruce (Picea abies) tissues that were not surface sterilized, we found that assembled sequences captured a mix of plant, lichen, and fungal transcripts. The latter were likely expressed by endophytic and epiphytic symbionts, indicating that these organisms were present, alive, and metabolically active. Here, we show that these serendipitously sequenced transcripts need not be considered merely as contamination, as is common, but that they provide insight into the plant's phyllosphere. Notably, we could classify these transcripts as originating predominantly from Dothideomycetes and Leotiomycetes species, with functional annotation of gene families indicating active growth and metabolism, with particular regards to glucose intake and processing, as well as gene regulation.


Assuntos
Fungos/genética , Picea/genética , Picea/microbiologia , Transcriptoma/genética , Composição de Bases/genética , Regulação Fúngica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
15.
Bioinformatics ; 31(12): 2054-5, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25661541

RESUMO

UNLABELLED: Whiteboard is a class library implemented in C++ that enables visualization to be tightly coupled with computation when analyzing large and complex datasets. AVAILABILITY AND IMPLEMENTATION: the C++ source code, coding samples and documentation are freely available under the Lesser General Public License from http://whiteboard-class.sourceforge.net/.


Assuntos
Biologia Computacional/métodos , Gráficos por Computador , Linguagens de Programação , Software , Bases de Dados Factuais , Humanos , Armazenamento e Recuperação da Informação
16.
Nature ; 518(7539): 371-5, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25686609

RESUMO

Darwin's finches, inhabiting the Galápagos archipelago and Cocos Island, constitute an iconic model for studies of speciation and adaptive evolution. Here we report the results of whole-genome re-sequencing of 120 individuals representing all of the Darwin's finch species and two close relatives. Phylogenetic analysis reveals important discrepancies with the phenotype-based taxonomy. We find extensive evidence for interspecific gene flow throughout the radiation. Hybridization has given rise to species of mixed ancestry. A 240 kilobase haplotype encompassing the ALX1 gene that encodes a transcription factor affecting craniofacial development is strongly associated with beak shape diversity across Darwin's finch species as well as within the medium ground finch (Geospiza fortis), a species that has undergone rapid evolution of beak shape in response to environmental changes. The ALX1 haplotype has contributed to diversification of beak shapes among the Darwin's finches and, thereby, to an expanded utilization of food resources.


Assuntos
Bico/anatomia & histologia , Evolução Molecular , Tentilhões/anatomia & histologia , Tentilhões/genética , Animais , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Equador , Feminino , Tentilhões/classificação , Tentilhões/embriologia , Fluxo Gênico , Genoma/genética , Haplótipos/genética , Hibridização Genética , Ilhas do Oceano Índico , Masculino , Dados de Sequência Molecular , Filogenia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
BMC Bioinformatics ; 15: 227, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24976580

RESUMO

BACKGROUND: Genomic duplications constitute major events in the evolution of species, allowing paralogous copies of genes to take on fine-tuned biological roles. Unambiguously identifying the orthology relationship between copies across multiple genomes can be resolved by synteny, i.e. the conserved order of genomic sequences. However, a comprehensive analysis of duplication events and their contributions to evolution would require all-to-all genome alignments, which increases at N2 with the number of available genomes, N. RESULTS: Here, we introduce Kraken, software that omits the all-to-all requirement by recursively traversing a graph of pairwise alignments and dynamically re-computing orthology. Kraken scales linearly with the number of targeted genomes, N, which allows for including large numbers of genomes in analyses. We first evaluated the method on the set of 12 Drosophila genomes, finding that orthologous correspondence computed indirectly through a graph of multiple synteny maps comes at minimal cost in terms of sensitivity, but reduces overall computational runtime by an order of magnitude. We then used the method on three well-annotated mammalian genomes, human, mouse, and rat, and show that up to 93% of protein coding transcripts have unambiguous pairwise orthologous relationships across the genomes. On a nucleotide level, 70 to 83% of exons match exactly at both splice junctions, and up to 97% on at least one junction. We last applied Kraken to an RNA-sequencing dataset from multiple vertebrates and diverse tissues, where we confirmed that brain-specific gene family members, i.e. one-to-many or many-to-many homologs, are more highly correlated across species than single-copy (i.e. one-to-one homologous) genes. Not limited to protein coding genes, Kraken also identifies thousands of newly identified transcribed loci, likely non-coding RNAs that are consistently transcribed in human, chimpanzee and gorilla, and maintain significant correlation of expression levels across species. CONCLUSIONS: Kraken is a computational genome coordinate translator that facilitates cross-species comparisons, distinguishes orthologs from paralogs, and does not require costly all-to-all whole genome mappings. Kraken is freely available under LPGL from http://github.com/nedaz/kraken.


Assuntos
Genômica/métodos , Software , Animais , Mapeamento Cromossômico , Drosophila melanogaster/genética , Evolução Molecular , Genoma/genética , Humanos , Camundongos , Anotação de Sequência Molecular , Ratos , Sintenia/genética , Transcrição Gênica
18.
Source Code Biol Med ; 9: 12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24976859

RESUMO

BACKGROUND: The fundamental challenge in optimally aligning homologous sequences is to define a scoring scheme that best reflects the underlying biological processes. Maximising the overall number of matches in the alignment does not always reflect the patterns by which nucleotides mutate. Efficiently implemented algorithms that can be parameterised to accommodate more complex non-linear scoring schemes are thus desirable. RESULTS: We present Cola, alignment software that implements different optimal alignment algorithms, also allowing for scoring contiguous matches of nucleotides in a nonlinear manner. The latter places more emphasis on short, highly conserved motifs, and less on the surrounding nucleotides, which can be more diverged. To illustrate the differences, we report results from aligning 14,100 sequences from 3' untranslated regions of human genes to 25 of their mammalian counterparts, where we found that a nonlinear scoring scheme is more consistent than a linear scheme in detecting short, conserved motifs. CONCLUSIONS: Cola is freely available under LPGL from https://github.com/nedaz/cola.

19.
PLoS One ; 9(3): e91172, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24625832

RESUMO

The domestic dog, Canis familiaris, is a well-established model system for mapping trait and disease loci. While the original draft sequence was of good quality, gaps were abundant particularly in promoter regions of the genome, negatively impacting the annotation and study of candidate genes. Here, we present an improved genome build, canFam3.1, which includes 85 MB of novel sequence and now covers 99.8% of the euchromatic portion of the genome. We also present multiple RNA-Sequencing data sets from 10 different canine tissues to catalog ∼175,000 expressed loci. While about 90% of the coding genes previously annotated by EnsEMBL have measurable expression in at least one sample, the number of transcript isoforms detected by our data expands the EnsEMBL annotations by a factor of four. Syntenic comparison with the human genome revealed an additional ∼3,000 loci that are characterized as protein coding in human and were also expressed in the dog, suggesting that those were previously not annotated in the EnsEMBL canine gene set. In addition to ∼20,700 high-confidence protein coding loci, we found ∼4,600 antisense transcripts overlapping exons of protein coding genes, ∼7,200 intergenic multi-exon transcripts without coding potential, likely candidates for long intergenic non-coding RNAs (lincRNAs) and ∼11,000 transcripts were reported by two different library construction methods but did not fit any of the above categories. Of the lincRNAs, about 6,000 have no annotated orthologs in human or mouse. Functional analysis of two novel transcripts with shRNA in a mouse kidney cell line altered cell morphology and motility. All in all, we provide a much-improved annotation of the canine genome and suggest regulatory functions for several of the novel non-coding transcripts.


Assuntos
Cães/genética , Genoma , Polimorfismo de Nucleotídeo Único , Animais , Linhagem Celular , Éxons , Perfilação da Expressão Gênica , Humanos , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Oligonucleotídeos Antissenso/química , Podócitos/citologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , RNA não Traduzido , Análise de Sequência de RNA
20.
Arch Iran Med ; 16(6): 324-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23725064

RESUMO

BACKGROUND: Despite the descending trends of gastric cancer in many parts of the world, its mortality rate has still remained high globally. Meat, red and processed meat in particular, may induce gastric carcinogenesis through potential mechanisms. However, the role of this dietary aspect in the risk of gastric cancer has not well been investigated so far. Therefore, we designed a study to assess the relation between meat consumption and the risk of gastric cancer in Golestan Province, a high- risk area for gastric malignancies in Iran. METHODS: Subjects of this population-based case-control study included 190 histologically confirmed cases of gastric cancer and 647 controls. Meat consumption was evaluated using a 116-item semi-quantitative food frequency questionnaire. A lifestyle questionnaire also collected data concerning demographic features, anthropometric measures, and other known risk factors of gastric cancer. We estimated crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the relation between meat intake and gastric cancer. RESULTS: After being adjusted for potential confounders, red meat intake was positively associated with gastric cancer which reached statistical significance (OR = 1.87, 95% CI: 1.01-3.47, Ptrend = 0.073). On the other hand, individuals in the highest quartile of white meat consumption had a statistically significant reduced risk of gastric cancer compared to those in the lowest quartile (OR = 0.36, 95% CI: 0.19-0.68, Ptrend = 0.005).  CONCLUSIONS: We observed a positive association between red meat consumption and the risk of gastric cancer, and a reverse relationship regarding white meat intake and the risk of this malignancy.


Assuntos
Dieta , Carne , Neoplasias Gástricas/epidemiologia , Idoso , Animais , Estudos de Casos e Controles , Bovinos , Galinhas , Feminino , Peixes , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Estilo de Vida , Masculino , Produtos da Carne , Pessoa de Meia-Idade , Fatores de Risco , Ovinos , Inquéritos e Questionários
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