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Learned vocal signals could be important in the formation of prezygotic isolation between two hybridising taxa. This study examined whether vocal variation in the parrot Platycercus elegans facilitates the separation of individuals from two subspecies, P. e. elegans (CR) and P. e. flaveolus (YR). CR and YR have very different plumage coloration, respectively deep crimson and pale yellow, but hybridise where they meet creating an intermediate population (WS). In a factorial design playback experiment, we conducted 108 playback trials on three focal populations (YR, WS, CR), in and around this area of hybridisation, to test if they respond differently to contact calls from their own or another population. We also analysed whether differences in acoustic variables of the stimulus calls predicted the response to the call. We did not find any indication that individuals from the three focal populations responded differently to calls sampled from their own or another subspecies. We did find an effect of two of the five acoustic variables that we used to describe and classify contact calls from the three source populations. Specifically, duration of the stimulus call positively affected the response from individuals from WS and negatively the response from CR, and CR responded more to stimulus calls with a lower peak frequency. Overall, we found no indication that acoustic variation in contact calls on a subspecies level is involved in maintaining plumage colour differences between P. e. elegans and P. e. flaveolus subspecies.  相似文献   
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Background

Recent reports have observed that individuals with serrated polyps, some of whom meet the clinical diagnostic criteria for Serrated Polyposis Syndrome (SPS), are among those who carry germline mutations in genes associated with polyposis syndromes including; (1) genes known to underlie hamartomatous polyposes (SMAD4, BMPR1A, and PTEN), (2) MUTYH-associated polyposis and (3) GREM1 in Hereditary Mixed Polyposis Syndrome (HMPS). The aim of this study was to characterise individuals fulfilling the current WHO criteria for SPS for germline mutations in these polyposis-associated genes.

Methods

A total of 65 individuals with SPS (fulfilling WHO criteria 1 or 3), were recruited to the Genetics of Serrated Neoplasia study between 2000 and 2012, through multiple Genetics or Family Cancer Clinics within Australia, or from the New Zealand Familial Gastrointestinal Cancer Service. Individuals with SPS were tested for coding mutations and large deletions in the PTEN, SMAD4, and BMPR1A genes, for the MUTYH variants in exons 7 (Y179C) and 13 (G396D), and for the duplication upstream of GREM1.

Results

We found no variants that were likely to be deleterious germline mutations in the SPS cases in the PTEN, SMAD4, and BMPR1A genes. A novel variant in intron 2 (c.164+223T>C) of PTEN was identified in one individual and was predicted by in silico analysis to have no functional consequences. One further individual with SPS was found to be mono-allelic for the MUTYH G396D mutation. No individuals carried the recently reported duplication within GREM1.

Conclusions

Genes involved in the gastrointestinal hamartomatous polyposis, Hereditary Mixed Polyposis Syndrome and MUTYH-associated polyposis syndromes are not commonly altered in individuals with SPS.  相似文献   
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Introduction: The HOXB13 pGly84Glu mutation has recently been associated with an increased risk of prostate cancer but the association of other cancer sites with this allele has not been assessed. Data has suggested that HOXB13 expression levels are decreased in colorectal cancer (CRC) cell lines indicating this gene may be involved in colorectal tumourigenesis. Methods: To evaluate a potential association of this mutation with CRC, we genotyped the mutation in 2695 CRC cases and 4593 controls from population-based registries in Canada and Australia. Results: The HOXB13 pGly84Glu mutation was more common in CRC cases than controls (0.48% vs. 0.17%, P = 0.02) indicating a significant association between the HOXB13 variant and CRC risk (OR = 2.8; 95%CI: 1.2–6.8). This association was attenuated but remained significant with the inclusion of previously published and publicly available genotype data. Pedigree analysis of cases and controls revealed that 7/21 HOXB13 mutation carriers had a family history of prostate cancer. Discussion: This report is the first to suggest a risk of CRC associated with mutations in the HOXB13 gene. These findings require further validation but may be of importance in the screening and genetic counseling of families known to carry the HOXB13 pGly84Glu mutation.  相似文献   
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BackgroundIn 2015, the United States Preventive Services Task Force (USPSTF) recommended targeted screening for prediabetes and diabetes (dysglycemia) in adults who are aged 40 to 70 y old and overweight or obese. Given increasing prevalence of dysglycemia at younger ages and lower body weight, particularly among racial/ethnic minorities, we sought to determine whether the current screening criteria may fail to identify some high-risk population subgroups.ConclusionsTargeted diabetes screening based on new USPSTF criteria may detect approximately half of adult community health center patients with undiagnosed dysglycemia and proportionately fewer racial/ethnic minorities than whites. Future research is needed to estimate the performance of these screening criteria in population-based samples.  相似文献   
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Pattern recognition receptors (PRRs) play a key role in plant and animal innate immunity. PRR binding of their cognate ligand triggers a signaling network and activates an immune response. Activation of PRR signaling must be controlled prior to ligand binding to prevent spurious signaling and immune activation. Flagellin perception in Arabidopsis through FLAGELLIN‐SENSITIVE 2 (FLS2) induces the activation of mitogen‐activated protein kinases (MAPKs) and immunity. However, the precise molecular mechanism that connects activated FLS2 to downstream MAPK cascades remains unknown. Here, we report the identification of a differentially phosphorylated MAP kinase kinase kinase that also interacts with FLS2. Using targeted proteomics and functional analysis, we show that MKKK7 negatively regulates flagellin‐triggered signaling and basal immunity and this requires phosphorylation of MKKK7 on specific serine residues. MKKK7 attenuates MPK6 activity and defense gene expression. Moreover, MKKK7 suppresses the reactive oxygen species burst downstream of FLS2, suggesting that MKKK7‐mediated attenuation of FLS2 signaling occurs through direct modulation of the FLS2 complex.  相似文献   
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Array based comparative genomic hybridisation (aCGH) is a powerful technique for detecting clinically relevant genome imbalance and can offer 40 to > 1000 times the resolution of karyotyping. Indeed, idiopathic learning disability (ILD) studies suggest that a genome-wide aCGH approach makes 10–15% more diagnoses involving genome imbalance than karyotyping. Despite this, aCGH has yet to be implemented as a routine NHS service. One significant obstacle is the perception that the technology is prohibitively expensive for most standard NHS clinical cytogenetics laboratories. To address this, we investigated the cost-effectiveness of aCGH versus standard cytogenetic analysis for diagnosing idiopathic learning disability (ILD) in the NHS. Cost data from four participating genetics centres were collected and analysed. In a single test comparison, the average cost of aCGH was £442 and the average cost of karyotyping was £117 with array costs contributing most to the cost difference. This difference was not a key barrier when the context of follow up diagnostic tests was considered. Indeed, in a hypothetical cohort of 100 ILD children, aCGH was found to cost less per diagnosis (£3,118) than a karyotyping and multi-telomere FISH approach (£4,957). We conclude that testing for genomic imbalances in ILD using microarray technology is likely to be cost-effective because long-term savings can be made regardless of a positive (diagnosis) or negative result. Earlier diagnoses save costs of additional diagnostic tests. Negative results are cost-effective in minimising follow-up test choice. The use of aCGH in routine clinical practice warrants serious consideration by healthcare providers. Copyright statement The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive licence (or non exclusive for government employees) on a worldwide basis to the BMJ Publishing Group Ltd, and its Licensees to permit this article (if accepted) to be published in BMJ editions and any other BMJPGL products and to exploit all subsidiary rights, as set out in our licence (bmj.com/advice/copyright.shtml). Authorship The authors included on this paper fulfil the criteria of authorship and no one who fulfils the criteria has been excluded from authorship. The authors made a substantial contribution to the conception, design, analysis and interpretation of data. They were involved in drafting the article or revising it critically for important intellectual content and approving the version to be published. Contributorship Sarah Wordsworth (Guarantor): Planning, conducting and reporting work, interpretation of data, drafting and revising article. James Buchanan: Conducting and reporting work, interpretation of data, revising article. Regina Regan: Completing costing questionnaire, providing protocol details, other costing information, interpretation of data, information about learning disability and genome imbalance and revising article. Val Davison: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting article. Kim Smith: Completing costing questionnaire, providing protocol details, drafting article. Sara Dyer: Completing costing questionnaire and providing protocol details. Carolyn Campbell: Completing costing questionnaire and providing protocol details. Edward Blair: Critical appraisal of article for clinical content and revising article. Eddy Maher: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting article. Jenny Taylor: Planning and facilitating work between centres. Drafting and revising article. Samantha JL Knight: Completing costing questionnaire, providing protocol details, other costing information, interpretation of data, providing information about learning disability and genome imbalance, drafting and revising article. Jenny Taylor and Samantha JL Knight contributed equally to the work presented.  相似文献   
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