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2.
HardwareX ; 15: e00443, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37795340

RESUMEN

Behaviour is the ultimate output of neural circuit computations, and therefore its analysis is a cornerstone of neuroscience research. However, every animal and experimental paradigm requires different illumination conditions to capture and, in some cases, manipulate specific behavioural features. This means that researchers often develop, from scratch, their own solutions and experimental set-ups. Here, we present OptoPi, an open source, affordable (∼ £600), behavioural arena with accompanying multi-animal tracking software. The system features highly customisable and reproducible visible and infrared illumination and allows for optogenetic stimulation. OptoPi acquires images using a Raspberry Pi camera, features motorised LED-based illumination, Arduino control, as well as irradiance monitoring to fine-tune illumination conditions with real time feedback. Our open-source software (BioImageProcessing) can be used to simultaneously track multiple unmarked animals both in on-line and off-line modes. We demonstrate the functionality of OptoPi by recording and tracking under different illumination conditions the spontaneous behaviour of larval zebrafish as well as adult Drosophila flies and their first instar larvae, an experimental animal that due to its small size and transparency has classically been hard to track. Further, we showcase OptoPi's optogenetic capabilities through a series of experiments using transgenic Drosophila larvae.

3.
Genome Biol ; 23(1): 35, 2022 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-35078504

RESUMEN

BACKGROUND: Genetic alterations of somatic cells can drive non-malignant clone formation and promote cancer initiation. However, the link between these processes remains unclear and hampers our understanding of tissue homeostasis and cancer development. RESULTS: Here, we collect a literature-based repertoire of 3355 well-known or predicted drivers of cancer and non-cancer somatic evolution in 122 cancer types and 12 non-cancer tissues. Mapping the alterations of these genes in 7953 pan-cancer samples reveals that, despite the large size, the known compendium of drivers is still incomplete and biased towards frequently occurring coding mutations. High overlap exists between drivers of cancer and non-cancer somatic evolution, although significant differences emerge in their recurrence. We confirm and expand the unique properties of drivers and identify a core of evolutionarily conserved and essential genes whose germline variation is strongly counter-selected. Somatic alteration in even one of these genes is sufficient to drive clonal expansion but not malignant transformation. CONCLUSIONS: Our study offers a comprehensive overview of our current understanding of the genetic events initiating clone expansion and cancer revealing significant gaps and biases that still need to be addressed. The compendium of cancer and non-cancer somatic drivers, their literature support, and properties are accessible in the Network of Cancer Genes and Healthy Drivers resource at http://www.network-cancer-genes.org/ .


Asunto(s)
Neoplasias , Oncogenes , Evolución Clonal , Humanos , Mutación , Neoplasias/genética , Neoplasias/patología
4.
Wellcome Open Res ; 6: 9, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34095506

RESUMEN

The ongoing pandemic of SARS-CoV-2 calls for rapid and cost-effective methods to accurately identify infected individuals. The vast majority of patient samples is assessed for viral RNA presence by RT-qPCR. Our biomedical research institute, in collaboration between partner hospitals and an accredited clinical diagnostic laboratory, established a diagnostic testing pipeline that has reported on more than 252,000 RT-qPCR results since its commencement at the beginning of April 2020. However, due to ongoing demand and competition for critical resources, alternative testing strategies were sought. In this work, we present a clinically-validated procedure for high-throughput SARS-CoV-2 detection by RT-LAMP in 25 minutes that is robust, reliable, repeatable, sensitive, specific, and inexpensive.

5.
Traffic ; 22(7): 240-253, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33914396

RESUMEN

Advancements in volume electron microscopy mean it is now possible to generate thousands of serial images at nanometre resolution overnight, yet the gold standard approach for data analysis remains manual segmentation by an expert microscopist, resulting in a critical research bottleneck. Although some machine learning approaches exist in this domain, we remain far from realizing the aspiration of a highly accurate, yet generic, automated analysis approach, with a major obstacle being lack of sufficient high-quality ground-truth data. To address this, we developed a novel citizen science project, Etch a Cell, to enable volunteers to manually segment the nuclear envelope (NE) of HeLa cells imaged with serial blockface scanning electron microscopy. We present our approach for aggregating multiple volunteer annotations to generate a high-quality consensus segmentation and demonstrate that data produced exclusively by volunteers can be used to train a highly accurate machine learning algorithm for automatic segmentation of the NE, which we share here, in addition to our archived benchmark data.


Asunto(s)
Aprendizaje Profundo , Células HeLa , Humanos , Microscopía Electrónica , Membrana Nuclear , Voluntarios
6.
Am J Hum Genet ; 98(6): 1092-1100, 2016 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-27236921

RESUMEN

Bacteremia (bacterial bloodstream infection) is a major cause of illness and death in sub-Saharan Africa but little is known about the role of human genetics in susceptibility. We conducted a genome-wide association study of bacteremia susceptibility in more than 5,000 Kenyan children as part of the Wellcome Trust Case Control Consortium 2 (WTCCC2). Both the blood-culture-proven bacteremia case subjects and healthy infants as controls were recruited from Kilifi, on the east coast of Kenya. Streptococcus pneumoniae is the most common cause of bacteremia in Kilifi and was thus the focus of this study. We identified an association between polymorphisms in a long intergenic non-coding RNA (lincRNA) gene (AC011288.2) and pneumococcal bacteremia and replicated the results in the same population (p combined = 1.69 × 10(-9); OR = 2.47, 95% CI = 1.84-3.31). The susceptibility allele is African specific, derived rather than ancestral, and occurs at low frequency (2.7% in control subjects and 6.4% in case subjects). Our further studies showed AC011288.2 expression only in neutrophils, a cell type that is known to play a major role in pneumococcal clearance. Identification of this novel association will further focus research on the role of lincRNAs in human infectious disease.


Asunto(s)
Bacteriemia/genética , Neumonía Neumocócica/genética , Polimorfismo Genético/genética , ARN Largo no Codificante/genética , Streptococcus pneumoniae/genética , Adolescente , Bacteriemia/microbiología , Bacteriemia/patología , Estudios de Casos y Controles , Niño , Preescolar , Estudio de Asociación del Genoma Completo , Humanos , Lactante , Recién Nacido , Kenia/epidemiología , Neumonía Neumocócica/microbiología , Neumonía Neumocócica/patología , Factores de Riesgo
7.
Nat Commun ; 5: 4204, 2014 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-25003214

RESUMEN

Dissecting how genetic and environmental influences impact on learning is helpful for maximizing numeracy and literacy. Here we show, using twin and genome-wide analysis, that there is a substantial genetic component to children's ability in reading and mathematics, and estimate that around one half of the observed correlation in these traits is due to shared genetic effects (so-called Generalist Genes). Thus, our results highlight the potential role of the learning environment in contributing to differences in a child's cognitive abilities at age twelve.


Asunto(s)
Dislexia/genética , Genética de Población , Matemática , Carácter Cuantitativo Heredable , Lectura , Gemelos/genética , Niño , Dislexia/psicología , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Aprendizaje , Masculino , Polimorfismo de Nucleótido Simple , Gemelos/psicología , Reino Unido
8.
Hum Mol Genet ; 23(12): 3316-26, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-24474471

RESUMEN

Identifying rare, highly penetrant risk mutations may be an important step in dissecting the molecular etiology of schizophrenia. We conducted a gene-based analysis of large (>100 kb), rare copy-number variants (CNVs) in the Wellcome Trust Case Control Consortium 2 (WTCCC2) schizophrenia sample of 1564 cases and 1748 controls all from Ireland, and further extended the analysis to include an additional 5196 UK controls. We found association with duplications at chr20p12.2 (P = 0.007) and evidence of replication in large independent European schizophrenia (P = 0.052) and UK bipolar disorder case-control cohorts (P = 0.047). A combined analysis of Irish/UK subjects including additional psychosis cases (schizophrenia and bipolar disorder) identified 22 carriers in 11 707 cases and 10 carriers in 21 204 controls [meta-analysis Cochran-Mantel-Haenszel P-value = 2 × 10(-4); odds ratio (OR) = 11.3, 95% CI = 3.7, ∞]. Nineteen of the 22 cases and 8 of the 10 controls carried duplications starting at 9.68 Mb with similar breakpoints across samples. By haplotype analysis and sequencing, we identified a tandem ~149 kb duplication overlapping the gene p21 Protein-Activated Kinase 7 (PAK7, also called PAK5) which was in linkage disequilibrium with local haplotypes (P = 2.5 × 10(-21)), indicative of a single ancestral duplication event. We confirmed the breakpoints in 8/8 carriers tested and found co-segregation of the duplication with illness in two additional family members of one of the affected probands. We demonstrate that PAK7 is developmentally co-expressed with another known psychosis risk gene (DISC1) suggesting a potential molecular mechanism involving aberrant synapse development and plasticity.


Asunto(s)
Trastorno Bipolar/genética , Duplicación Cromosómica , Proteínas del Tejido Nervioso/metabolismo , Trastornos Psicóticos/genética , Esquizofrenia/genética , Quinasas p21 Activadas/genética , Quinasas p21 Activadas/metabolismo , Trastorno Bipolar/patología , Estudios de Casos y Controles , Puntos de Rotura del Cromosoma , Variaciones en el Número de Copia de ADN , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Desequilibrio de Ligamiento , Masculino , Plasticidad Neuronal , Trastornos Psicóticos/patología , Esquizofrenia/patología , Población Blanca/genética
9.
Biol Psychiatry ; 75(5): 386-97, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23871474

RESUMEN

BACKGROUND: Genome-wide association studies (GWAS) have identified several loci associated with schizophrenia and/or bipolar disorder. We performed a GWAS of psychosis as a broad syndrome rather than within specific diagnostic categories. METHODS: 1239 cases with schizophrenia, schizoaffective disorder, or psychotic bipolar disorder; 857 of their unaffected relatives, and 2739 healthy controls were genotyped with the Affymetrix 6.0 single nucleotide polymorphism (SNP) array. Analyses of 695,193 SNPs were conducted using UNPHASED, which combines information across families and unrelated individuals. We attempted to replicate signals found in 23 genomic regions using existing data on nonoverlapping samples from the Psychiatric GWAS Consortium and Schizophrenia-GENE-plus cohorts (10,352 schizophrenia patients and 24,474 controls). RESULTS: No individual SNP showed compelling evidence for association with psychosis in our data. However, we observed a trend for association with same risk alleles at loci previously associated with schizophrenia (one-sided p = .003). A polygenic score analysis found that the Psychiatric GWAS Consortium's panel of SNPs associated with schizophrenia significantly predicted disease status in our sample (p = 5 × 10(-14)) and explained approximately 2% of the phenotypic variance. CONCLUSIONS: Although narrowly defined phenotypes have their advantages, we believe new loci may also be discovered through meta-analysis across broad phenotypes. The novel statistical methodology we introduced to model effect size heterogeneity between studies should help future GWAS that combine association evidence from related phenotypes. Applying these approaches, we highlight three loci that warrant further investigation. We found that SNPs conveying risk for schizophrenia are also predictive of disease status in our data.


Asunto(s)
Polimorfismo de Nucleótido Simple/genética , Trastornos Psicóticos/genética , Esquizofrenia/genética , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Fenotipo , Análisis de Componente Principal
10.
Nat Genet ; 45(2): 208-13, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23291585

RESUMEN

To identify susceptibility loci for visceral leishmaniasis, we undertook genome-wide association studies in two populations: 989 cases and 1,089 controls from India and 357 cases in 308 Brazilian families (1,970 individuals). The HLA-DRB1-HLA-DQA1 locus was the only region to show strong evidence of association in both populations. Replication at this region was undertaken in a second Indian population comprising 941 cases and 990 controls, and combined analysis across the three cohorts for rs9271858 at this locus showed P(combined) = 2.76 × 10(-17) and odds ratio (OR) = 1.41, 95% confidence interval (CI) = 1.30-1.52. A conditional analysis provided evidence for multiple associations within the HLA-DRB1-HLA-DQA1 region, and a model in which risk differed between three groups of haplotypes better explained the signal and was significant in the Indian discovery and replication cohorts. In conclusion, the HLA-DRB1-HLA-DQA1 HLA class II region contributes to visceral leishmaniasis susceptibility in India and Brazil, suggesting shared genetic risk factors for visceral leishmaniasis that cross the epidemiological divides of geography and parasite species.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Cadenas alfa de HLA-DQ/genética , Cadenas HLA-DRB1/genética , Leishmaniasis Visceral/genética , Brasil , Electroforesis en Gel de Agar , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Haplotipos/genética , Humanos , India , Modelos Lineales , Oportunidad Relativa , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple/genética
11.
Nat Genet ; 44(12): 1341-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23143594

RESUMEN

To gain further insight into the genetic architecture of psoriasis, we conducted a meta-analysis of 3 genome-wide association studies (GWAS) and 2 independent data sets genotyped on the Immunochip, including 10,588 cases and 22,806 controls. We identified 15 new susceptibility loci, increasing to 36 the number associated with psoriasis in European individuals. We also identified, using conditional analyses, five independent signals within previously known loci. The newly identified loci shared with other autoimmune diseases include candidate genes with roles in regulating T-cell function (such as RUNX3, TAGAP and STAT3). Notably, they included candidate genes whose products are involved in innate host defense, including interferon-mediated antiviral responses (DDX58), macrophage activation (ZC3H12C) and nuclear factor (NF)-κB signaling (CARD14 and CARM1). These results portend a better understanding of shared and distinctive genetic determinants of immune-mediated inflammatory disorders and emphasize the importance of the skin in innate and acquired host defense.


Asunto(s)
Sitios Genéticos , Predisposición Genética a la Enfermedad , Inmunidad Innata/genética , Psoriasis/genética , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/inmunología , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 3 del Factor de Unión al Sitio Principal/inmunología , Proteína 58 DEAD Box , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/inmunología , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/inmunología , Estudio de Asociación del Genoma Completo , Guanilato Ciclasa/genética , Guanilato Ciclasa/inmunología , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Psoriasis/inmunología , Receptores Inmunológicos , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/inmunología , Piel/inmunología , Linfocitos T/inmunología , Población Blanca/genética
12.
Nat Genet ; 44(10): 1131-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22961001

RESUMEN

Barrett's esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia, and it strongly predisposes to esophageal adenocarcinoma (EAC), a tumor with a very poor prognosis. We report the first genome-wide association study on Barrett's esophagus, comprising 1,852 UK cases and 5,172 UK controls in the discovery stage and 5,986 cases and 12,825 controls in the replication stage. Variants at two loci were associated with disease risk: chromosome 6p21, rs9257809 (Pcombined=4.09×10(-9); odds ratio (OR)=1.21, 95% confidence interval (CI)=1.13-1.28), within the major histocompatibility complex locus, and chromosome 16q24, rs9936833 (Pcombined=2.74×10(-10); OR=1.14, 95% CI=1.10-1.19), for which the closest protein-coding gene is FOXF1, which is implicated in esophageal development and structure. We found evidence that many common variants of small effect contribute to genetic susceptibility to Barrett's esophagus and that SNP alleles predisposing to obesity also increase risk for Barrett's esophagus.


Asunto(s)
Esófago de Barrett/genética , Cromosomas Humanos Par 16 , Predisposición Genética a la Enfermedad , Complejo Mayor de Histocompatibilidad , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Sitios Genéticos , Estudio de Asociación del Genoma Completo , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Modelos Genéticos
13.
Science ; 337(6094): 584-7, 2012 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-22798408

RESUMEN

Arabidopsis thaliana accessions have adapted to growth in a wide range of climates. Variation in flowering and alignment of vernalization response with winter length are central to this adaptation. Vernalization involves the epigenetic silencing of the floral repressor FLC via a conserved Polycomb (PRC2) mechanism involving trimethylation of Lys(27) on histone H3 (H3K27me3). We found that variation for response to winter length maps to cis polymorphism within FLC. A rare combination of four polymorphisms localized around the nucleation region of a PHD-Polycomb complex determines a need for longer cold. Chromatin immunoprecipitation experiments indicate that these polymorphisms influence the accumulation of H3K27me3 in Arabidopsis accession Lov-1, both at the nucleation site and over the gene body. Quantitative modulation of chromatin silencing through cis variation may be a general mechanism contributing to evolutionary change.


Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Frío , Flores/genética , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Proteínas de Dominio MADS/genética , Proteínas Represoras/metabolismo , Arabidopsis/crecimiento & desarrollo , Cromatina/genética , Cromatina/metabolismo , Inmunoprecipitación de Cromatina , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos , Flores/crecimiento & desarrollo , Histonas/genética , Histonas/metabolismo , Lisina/genética , Lisina/metabolismo , Metilación , Complejo Represivo Polycomb 2 , Proteínas del Grupo Polycomb , Polimorfismo Genético , Proteínas Represoras/genética , Estaciones del Año
14.
Nat Genet ; 44(3): 328-33, 2012 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-22306652

RESUMEN

Genetic factors have been implicated in stroke risk, but few replicated associations have been reported. We conducted a genome-wide association study (GWAS) for ischemic stroke and its subtypes in 3,548 affected individuals and 5,972 controls, all of European ancestry. Replication of potential signals was performed in 5,859 affected individuals and 6,281 controls. We replicated previous associations for cardioembolic stroke near PITX2 and ZFHX3 and for large vessel stroke at a 9p21 locus. We identified a new association for large vessel stroke within HDAC9 (encoding histone deacetylase 9) on chromosome 7p21.1 (including further replication in an additional 735 affected individuals and 28,583 controls) (rs11984041; combined P = 1.87 × 10(-11); odds ratio (OR) = 1.42, 95% confidence interval (CI) = 1.28-1.57). All four loci exhibited evidence for heterogeneity of effect across the stroke subtypes, with some and possibly all affecting risk for only one subtype. This suggests distinct genetic architectures for different stroke subtypes.


Asunto(s)
Cromosomas Humanos Par 7/genética , Predisposición Genética a la Enfermedad/genética , Histona Desacetilasas/genética , Proteínas Represoras/genética , Accidente Cerebrovascular/genética , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Oportunidad Relativa , Polimorfismo de Nucleótido Simple/genética , Población Blanca/genética
15.
Bioinformatics ; 28(1): 134-5, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22057162

RESUMEN

SUMMARY: High-throughput genotyping arrays provide an efficient way to survey single nucleotide polymorphisms (SNPs) across the genome in large numbers of individuals. Downstream analysis of the data, for example in genome-wide association studies (GWAS), often involves statistical models of genotype frequencies across individuals. The complexities of the sample collection process and the potential for errors in the experimental assay can lead to biases and artefacts in an individual's inferred genotypes. Rather than attempting to model these complications, it has become a standard practice to remove individuals whose genome-wide data differ from the sample at large. Here we describe a simple, but robust, statistical algorithm to identify samples with atypical summaries of genome-wide variation. Its use as a semi-automated quality control tool is demonstrated using several summary statistics, selected to identify different potential problems, and it is applied to two different genotyping platforms and sample collections. AVAILABILITY: The algorithm is written in R and is freely available at www.well.ox.ac.uk/chris-spencer CONTACT: chris.spencer@well.ox.ac.uk SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Algoritmos , Análisis por Conglomerados , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Estudios de Cohortes , Femenino , Humanos , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos
16.
Nature ; 476(7359): 214-9, 2011 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-21833088

RESUMEN

Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Inmunidad Celular/inmunología , Esclerosis Múltiple/genética , Esclerosis Múltiple/inmunología , Alelos , Diferenciación Celular/inmunología , Europa (Continente)/etnología , Genoma Humano/genética , Estudio de Asociación del Genoma Completo , Antígenos HLA-A/genética , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Humanos , Inmunidad Celular/genética , Complejo Mayor de Histocompatibilidad/genética , Polimorfismo de Nucleótido Simple/genética , Tamaño de la Muestra , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/inmunología
17.
PLoS One ; 6(5): e19949, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21625501

RESUMEN

We have explored the genetic basis of variation in vernalization requirement and response in Arabidopsis accessions, selected on the basis of their phenotypic distinctiveness. Phenotyping of F2 populations in different environments, plus fine mapping, indicated possible causative genes. Our data support the identification of FRI and FLC as candidates for the major-effect QTL underlying variation in vernalization response, and identify a weak FLC allele, caused by a Mutator-like transposon, contributing to flowering time variation in two N. American accessions. They also reveal a number of additional QTL that contribute to flowering time variation after saturating vernalization. One of these was the result of expression variation at the FT locus. Overall, our data suggest that distinct phenotypic variation in the vernalization and flowering response of Arabidopsis accessions is accounted for by variation that has arisen independently at relatively few major-effect loci.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Frío , Flores/fisiología , Variación Genética , Proteínas de Dominio MADS/genética , Sitios de Carácter Cuantitativo , Alelos , Arabidopsis/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Fenotipo , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Nat Genet ; 43(2): 117-20, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21186350

RESUMEN

Metformin is the most commonly used pharmacological therapy for type 2 diabetes. We report a genome-wide association study for glycemic response to metformin in 1,024 Scottish individuals with type 2 diabetes with replication in two cohorts including 1,783 Scottish individuals and 1,113 individuals from the UK Prospective Diabetes Study. In a combined meta-analysis, we identified a SNP, rs11212617, associated with treatment success (n = 3,920, P = 2.9 × 10(-9), odds ratio = 1.35, 95% CI 1.22-1.49) at a locus containing ATM, the ataxia telangiectasia mutated gene. In a rat hepatoma cell line, inhibition of ATM with KU-55933 attenuated the phosphorylation and activation of AMP-activated protein kinase in response to metformin. We conclude that ATM, a gene known to be involved in DNA repair and cell cycle control, plays a role in the effect of metformin upstream of AMP-activated protein kinase, and variation in this gene alters glycemic response to metformin.


Asunto(s)
Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/genética , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Metformina/farmacología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Supresoras de Tumor/genética , Animales , Proteínas de la Ataxia Telangiectasia Mutada , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Relación Dosis-Respuesta a Droga , Estudio de Asociación del Genoma Completo , Humanos , Hipoglucemiantes/farmacología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Polimorfismo de Nucleótido Simple , Proteínas Quinasas/metabolismo , Ratas , Escocia
19.
Hum Mol Genet ; 20(2): 345-53, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21044948

RESUMEN

We performed a genome-wide association study (GWAS) in 1705 Parkinson's disease (PD) UK patients and 5175 UK controls, the largest sample size so far for a PD GWAS. Replication was attempted in an additional cohort of 1039 French PD cases and 1984 controls for the 27 regions showing the strongest evidence of association (P< 10(-4)). We replicated published associations in the 4q22/SNCA and 17q21/MAPT chromosome regions (P< 10(-10)) and found evidence for an additional independent association in 4q22/SNCA. A detailed analysis of the haplotype structure at 17q21 showed that there are three separate risk groups within this region. We found weak but consistent evidence of association for common variants located in three previously published associated regions (4p15/BST1, 4p16/GAK and 1q32/PARK16). We found no support for the previously reported SNP association in 12q12/LRRK2. We also found an association of the two SNPs in 4q22/SNCA with the age of onset of the disease.


Asunto(s)
Cromosomas Humanos Par 17/genética , Predisposición Genética a la Enfermedad , Enfermedad de Parkinson/genética , alfa-Sinucleína/genética , Edad de Inicio , Estudios de Casos y Controles , Estudio de Asociación del Genoma Completo , Haplotipos , Humanos , Polimorfismo de Nucleótido Simple , Tamaño de la Muestra , Población Blanca
20.
Nat Genet ; 42(11): 985-90, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20953190

RESUMEN

To identify new susceptibility loci for psoriasis, we undertook a genome-wide association study of 594,224 SNPs in 2,622 individuals with psoriasis and 5,667 controls. We identified associations at eight previously unreported genomic loci. Seven loci harbored genes with recognized immune functions (IL28RA, REL, IFIH1, ERAP1, TRAF3IP2, NFKBIA and TYK2). These associations were replicated in 9,079 European samples (six loci with a combined P < 5 × 10⁻8 and two loci with a combined P < 5 × 10⁻7). We also report compelling evidence for an interaction between the HLA-C and ERAP1 loci (combined P = 6.95 × 10⁻6). ERAP1 plays an important role in MHC class I peptide processing. ERAP1 variants only influenced psoriasis susceptibility in individuals carrying the HLA-C risk allele. Our findings implicate pathways that integrate epidermal barrier dysfunction with innate and adaptive immune dysregulation in psoriasis pathogenesis.


Asunto(s)
Aminopeptidasas/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Antígenos HLA-C/genética , Psoriasis/genética , Mapeo Cromosómico , Cromosomas Humanos/genética , Cromosomas Humanos X/genética , Europa (Continente) , Variación Genética , Humanos , Complejo Mayor de Histocompatibilidad/genética , Antígenos de Histocompatibilidad Menor , Polimorfismo de Nucleótido Simple , Valores de Referencia , Medición de Riesgo
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