Wellcome Trust Centre for Human Genetics

About: Wellcome Trust Centre for Human Genetics is a facility organization based out in Oxford, United Kingdom. It is known for research contribution in the topics: Population & Genome-wide association study. The organization has 2122 authors who have published 4269 publications receiving 433899 citations.

Identifying lineage effects when controlling for population structure improves power in bacterial association studies

Abstract: Bacteria pose unique challenges for genome-wide association studies because of strong structuring into distinct strains and substantial linkage disequilibrium across the genome(1,2). Although methods developed for human studies can correct for strain structure(3,4), this risks considerable loss-of-power because genetic differences between strains often contribute substantial phenotypic variability(5). Here, we propose a new method that captures lineage-level associations even when locus-specific associations cannot be fine-mapped. We demonstrate its ability to detect genes and genetic variants underlying resistance to 17 antimicrobials in 3,144 isolates from four taxonomically diverse clonal and recombining bacteria: Mycobacterium tuberculosis, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Strong selection, recombination and penetrance confer high power to recover known antimicrobial resistance mechanisms and reveal a candidate association between the outer membrane porin nmpC and cefazolin resistance in E. coli. Hence, our method pinpoints locus-specific effects where possible and boosts power by detecting lineage-level differences when fine-mapping is intractable.

British Society of Gastroenterology position statement on serrated polyps in the colon and rectum

Abstract: Serrated polyps have been recognised in the last decade as important premalignant lesions accounting for between 15% and 30% of colorectal cancers. There is therefore a clinical need for guidance on how to manage these lesions; however, the evidence base is limited. A working group was commission by the British Society of Gastroenterology (BSG) Endoscopy section to review the available evidence and develop a position statement to provide clinical guidance until the evidence becomes available to support a formal guideline. The scope of the position statement was wide-ranging and included: evidence that serrated lesions have premalignant potential; detection and resection of serrated lesions; surveillance strategies after detection of serrated lesions; special situations—serrated polyposis syndrome (including surgery) and serrated lesions in colitis; education, audit and benchmarks and research questions. Statements on these issues were proposed where the evidence was deemed sufficient, and reevaluated modified via a Delphi process until >80% agreement was reached. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool was used to assess the strength of evidence and strength of recommendation for finalised statements. Key recommendation: we suggest that until further evidence on the efficacy or otherwise of surveillance are published, patients with sessile serrated lesions (SSLs) that appear associated with a higher risk of future neoplasia or colorectal cancer (SSLs ≥10 mm or serrated lesions harbouring dysplasia including traditional serrated adenomas) should be offered a one-off colonoscopic surveillance examination at 3 years (weak recommendation, low quality evidence, 90% agreement).

hsa‐miR‐210 is a marker of tumor hypoxia and a prognostic factor in head and neck cancer

Abstract: BACKGROUND: Hypoxia is an important mechanism of treatment resistance in head and neck squamous cell carcinoma (HNSCC). MicroRNAs are short noncoding RNAs that regulate multiple mRNAs and are frequently dysregulated in cancer. The authors have investigated the role of 3 microRNAs, including the hypoxia-induced hsa-miR-210, as potential markers of hypoxia or prognosis. METHODS: Three hypoxia-related microRNAs, hsa-miR-210, hsa-miR-21, and hsa-miR-10b, were measured in 46 samples from patients with HNSCC. Expression levels were correlated with clinicopathological variables and other markers of hypoxia: a published 99-gene hypoxia metagene, individual hypoxia-related genes such as TWIST1, and immunohistochemical expression of hypoxia-inducible factor 1 and its target gene carbonic anhydrase 9. We then performed survival analyses to investigate the prognostic significance of these microRNAs. RESULTS: Only the level of hsa-miR-210 was significantly correlated with other markers of hypoxia, including the 99-gene hypoxia metagene (rho = 0.67, P < .001). We found no association between hsa-miR-210, hsa-miR-21, or hsa-miR-10b and clinicopathological variables such as tumor size, differentiation, and stage. However, high levels of hsa-miR-210 were associated with locoregional disease recurrence (P = .001) and short overall survival (P = .008). hsa-miR-21 and hsa-miR-10b had no prognostic significance. CONCLUSIONS: Expression of hsa-miR-210 in head and neck cancer correlates with other approaches for assessing hypoxia and is associated with prognosis. This warrants further study as a classification marker of patients for therapies involving modulation of hypoxia. Cancer 2010. © 2010 American Cancer Society.