1,324 research outputs found
Familial genetic risks:How can we better navigate patient confidentiality and appropriate risk disclosure to relatives?
This article investigates a high-profile and ongoing dilemma for healthcare professionals (HCPs), namely whether the existence of a (legal) duty of care to genetic relatives of a patient is a help or a hindrance in deciding what to do in cases where a patient's genetic information may have relevance to the health of the patient's family members. The English case ABC v St George's Healthcare NHS Trust and others considered if a duty of confidentiality owed to the patient and a putative duty of care to the patient's close relatives could coexist in this context. This article examines whether embracing the concept of coexisting duties could enable HCPs to respect duties in line with their clinical judgement, thereby providing legal support and clarity to professionals to allow them to provide the best possible genetics service to both the patient and their family. We argue that these dual duties, framed as a novel, composite duty to consider the interests of genetic relatives, could allow HCPs to exercise and act on their professional judgements about the relative value of information to family members, without fears of liability for negligence or breach of confidence
A Mechanistic Basis for the Coordinated Regulation of Pharyngeal Morphogenesis in Caenorhabditis elegans by LIN-35/Rb and UBC-18–ARI-1
Genetic redundancy, whereby two genes carry out seemingly overlapping functions, may in large part be attributable to the intricacy and robustness of genetic networks that control many developmental processes. We have previously described a complex set of genetic interactions underlying foregut development in the nematode Caenorhabditis elegans. Specifically, LIN-35/Rb, a tumor suppressor ortholog, in conjunction with UBC-18–ARI-1, a conserved E2/E3 complex, and PHA-1, a novel protein, coordinately regulates an early step of pharyngeal morphogenesis involving cellular re-orientation. Functional redundancy is indicated by the observation that lin-35; ubc-18 double mutants, as well as certain allelic combinations of pha-1 with either lin-35 or ubc-18, display defects in pharyngeal development, whereas single mutants do not. Using a combination of genetic and molecular analyses, we show that sup-35, a strong recessive suppressor of pha-1–associated lethality, also reverts the synthetic lethality of lin-35; ubc-18, lin-35; pha-1, and ubc-18 pha-1 double mutants. SUP-35, which contains C2H2-type Zn-finger domains as well as a conserved RMD-like motif, showed a dynamic pattern of subcellular localization during embryogenesis. We find that mutations in sup-35 specifically suppress hypomorphic alleles of pha-1 and that SUP-35, acting genetically upstream of SUP-36 and SUP-37, negatively regulates pha-1 transcription. We further demonstrate that LIN-35, a transcriptional repressor, and UBC-18–ARI-1, a complex involved in ubiquitin-mediated proteolysis, negatively regulate SUP-35 abundance through distinct mechanisms. We also show that HCF-1, a C. elegans homolog of host cell factor 1, functionally antagonizes LIN-35 in the regulation of sup-35. Our cumulative findings piece together the components of a novel regulatory network that includes LIN-35/Rb, which functions to control organ morphogenesis. Our results also shed light on general mechanisms that may underlie developmental genetic redundancies as well as principles that may govern complex disease traits
An Exploration of Fetish Social Networks and Communities
Online Social Networks (OSNs) provide a venue for virtual interactions and relationships between individuals. In some communities, OSNs also facilitate arranging offline meetings and relationships. FetLife, the world’s largest anonymous social network for the BDSM, fetish and kink communities, provides a unique example of an OSN that serves as an interaction space, community organizing tool, and sexual market. In this paper, we present a first look at the characteristics of European members of Fetlife, comprising 504,416 individual nodes with 1,912,196 connections. We looked at user characteristics in terms of gender, sexual orientation, and preferred role. We further examined the homophilic communities and find that women in particular are far more platonically involved on the site than straight males. Our results suggest there are important differences between the FetLife community and conventional OSNs
Coordinated Regulation of Intestinal Functions in C. elegans by LIN-35/Rb and SLR-2
LIN-35 is the sole C. elegans representative of the pocket protein family, which includes the mammalian Retinoblastoma protein pRb and its paralogs p107 and p130. In addition to having a well-established and central role in cell cycle regulation, pocket proteins have been increasingly implicated in the control of critical and diverse developmental and cellular processes. To gain a greater understanding of the roles of pocket proteins during development, we have characterized a synthetic genetic interaction between lin-35 and slr-2, which we show encodes a C2H2-type Zn-finger protein. Whereas animals harboring single mutations in lin-35 or slr-2 are viable and fertile, lin-35; slr-2 double mutants arrest uniformly in early larval development without obvious morphological defects. Using a combination of approaches including transcriptome profiling, mosaic analysis, starvation assays, and expression analysis, we demonstrate that both LIN-35 and SLR-2 act in the intestine to regulate the expression of many genes required for normal nutrient utilization. These findings represent a novel role for pRb family members in the maintenance of organ function. Our studies also shed light on the mechanistic basis of genetic redundancy among transcriptional regulators and suggest that synthetic interactions may result from the synergistic misregulation of one or more common targets
Strong signature of natural selection within an FHIT intron implicated in prostate cancer risk
Previously, a candidate gene linkage approach on brother pairs affected with prostate cancer identified a locus of prostate cancer susceptibility at D3S1234 within the fragile histidine triad gene (FHIT), a tumor suppressor that induces apoptosis. Subsequent association tests on 16 SNPs spanning approximately 381 kb surrounding D3S1234 in Americans of European descent revealed significant evidence of association for a single SNP within intron 5 of FHIT. In the current study, resequencing and genotyping within a 28.5 kb region surrounding this SNP further delineated the association with prostate cancer risk to a 15 kb region. Multiple SNPs in sequences under evolutionary constraint within intron 5 of FHIT defined several related haplotypes with an increased risk of prostate cancer in European-Americans. Strong associations were detected for a risk haplotype defined by SNPs 138543, 142413, and 152494 in all cases (Pearson's χ2 = 12.34, df 1, P = 0.00045) and for the homozygous risk haplotype defined by SNPs 144716, 142413, and 148444 in cases that shared 2 alleles identical by descent with their affected brothers (Pearson's χ2 = 11.50, df 1, P = 0.00070). In addition to highly conserved sequences encompassing SNPs 148444 and 152413, population studies revealed strong signatures of natural selection for a 1 kb window covering the SNP 144716 in two human populations, the European American (π = 0.0072, Tajima's D= 3.31, 14 SNPs) and the Japanese (π = 0.0049, Fay & Wu's H = 8.05, 14 SNPs), as well as in chimpanzees (Fay & Wu's H = 8.62, 12 SNPs). These results strongly support the involvement of the FHIT intronic region in an increased risk of prostate cancer. © 2008 Ding et al
Potential conservation of circadian clock proteins in the phylum Nematoda as revealed by bioinformatic searches
Although several circadian rhythms have been described in C. elegans, its molecular clock remains elusive. In this work we employed a novel bioinformatic approach, applying probabilistic methodologies, to search for circadian clock proteins of several of the best studied circadian model organisms of different taxa (Mus musculus, Drosophila melanogaster, Neurospora crassa, Arabidopsis thaliana and Synechoccocus elongatus) in the proteomes of C. elegans and other members of the phylum Nematoda. With this approach we found that the Nematoda contain proteins most related to the core and accessory proteins of the insect and mammalian clocks, which provide new insights into the nematode clock and the evolution of the circadian system.Fil: Romanowski, Andrés. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones BioquÃmicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones BioquÃmicas de Buenos Aires; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologÃa. Laboratorio de CronobiologÃa; ArgentinaFil: Garavaglia, MatÃas Javier. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologÃa. Laboratorio de Ing.genética y Biolog.molecular y Celular. Area Virus de Insectos; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Goya, MarÃa Eugenia. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologÃa. Laboratorio de CronobiologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Ghiringhelli, Pablo Daniel. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologÃa. Laboratorio de Ing.genética y Biolog.molecular y Celular. Area Virus de Insectos; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Golombek, Diego Andres. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologÃa. Laboratorio de CronobiologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentin
Evaluation of a new, rapid, simple test for the detection of influenza virus
BACKGROUND: Influenza virus infections are responsible for significant morbidity and mortality in both pediatric and adult populations worldwide. Rapid and accurate diagnosis of influenza is necessary for appropriate patient management during the influenza season and for optimal utilization of anti-influenza therapy. We prospectively tested the accuracy of a simple and rapid diagnostic method. METHODS: Ninety-eight samples (nasal and pharyngeal swabs) from patients with upper respiratory tract infection symptoms who presented to primary healthcare centres in Barcelona (Spain) were prospectively analyzed. The samples were collected as part of influenza surveillance program. Samples that had enough volume to make the new test after aliquoting the amount needed to perform routine tests were included. None of the samples were pre-selected as a result of their status in relation to influenza virus. Samples were analyzed by in-house real-time PCR and Alereâ„¢ i Influenza A & B (Alereâ„¢ i), which uses isothermal amplification of nucleic acids for the qualitative detection of influenza A and B in nasal swabs transported in viral transport media. The two techniques were compared by positive percent agreement (PPA) and negative percent agreement (NPA). Statistical analysis was performed with Stata. RESULTS: Of the 98 samples analysed 90 were concordant; 46 (46.9%) were positive and 44 (44.9%) were negative. Five samples showed invalid results with the Alereâ„¢ i test and could be not re-tested due to insufficient sample volume and were not included in the final statistical analysis. In the 93 remaining samples, the Alereâ„¢ i test showed 97% of accuracy having correctly classified 90 samples. We obtained discordant results in 3 samples (3%). The PPA was 93.8% for influenza A and 94.1% for influenza B, and NPA was 100% for influenza A and influenza B virus. In addition, the Alereâ„¢ i was very rapid (15Â minutes or less) and extremely easy to use. CONCLUSIONS: The Alereâ„¢ i test provided a good correlation compared to the real-time PCR test for the diagnosis of influenza. Since this method can be performed in minutes, it allows immediate, accurate clinical decisions to prescribe appropriate antiviral treatment or isolation of patients
Composite likelihood estimation of demographic parameters
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Most existing likelihood-based methods for fitting historical demographic models to DNA sequence polymorphism data to do not scale feasibly up to the level of whole-genome data sets. Computational economies can be achieved by incorporating two forms of pseudo-likelihood: composite and approximate likelihood methods. Composite likelihood enables scaling up to large data sets because it takes the product of marginal likelihoods as an estimator of the likelihood of the complete data set. This approach is especially useful when a large number of genomic regions constitutes the data set. Additionally, approximate likelihood methods can reduce the dimensionality of the data by summarizing the information in the original data by either a sufficient statistic, or a set of statistics. Both composite and approximate likelihood methods hold promise for analyzing large data sets or for use in situations where the underlying demographic model is complex and has many parameters. This paper considers a simple demographic model of allopatric divergence between two populations, in which one of the population is hypothesized to have experienced a founder event, or population bottleneck. A large resequencing data set from human populations is summarized by the joint frequency spectrum, which is a matrix of the genomic frequency spectrum of derived base frequencies in two populations. A Bayesia
Use of AFLP and RAPD molecular genetic markers and cytogenetic analysis to explore relationships among taxa of the Patagonian Bromus setifolius complex
Bromus setifolius var. pictus (Hook) Skottsb., B. setifolius var. setifolius Presl. and B.setifolius var. brevifolius Ness are three native Patagonian taxa in the section Pnigma Dumort of the genus Bromus L. AFLP and RAPD analysis, in conjunction with genetic distance measurements and statistical techniques, revealed variation within this group and indicated that B. setifolius var. brevifolius was closely related to B. setifolius var. pictus, with both taxa being more distantly related to B. setifolius var. setifolius. Cytogenetic analysis confirmed the chromosomal number of B. setifolius var. pictus (2n = 70) and B. setifolius var. setifolius (2n = 28) and showed for the first time that B. setifolius var. brevifolius had 2n = 70. The combination of molecular genetic and cytogenetic evidence supported a species status for two of the three taxa and suggested hypotheses for the evolutionary origin of these complex taxa. Species status was also indicated for B. setifolius var. setifolius. Based on these findings, we suggest that B. setifolius var. pictus be referred to as B. pictus Hook var. pictus, and B. setifolius var brevifolius as B. pictus Hook var brevifolius. The correlation between AFLP diversity and variation in ecological parameters suggested that this marker system could be used to assess breeding progress and to monitor the domestication of Patagonian Bromus species for agronomic use
The clinical meaningfulness of ADAS-Cog changes in Alzheimer's disease patients treated with donepezil in an open-label trial
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