Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022104 (irritable bowel syndrome)
 8,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Genome-wide association studies (GWAS) are popular for identifying genetic variants which are associated with disease risk. Many approaches have been proposed to test multiple single nucleotide polymorphisms (SNPs) in a region simultaneously which considering disadvantages of methods in single locus association analysis. Kernel machine based SNP set analysis is more powerful than single locus analysis, which borrows information from SNPs correlated with causal or tag SNPs. Four types of kernel machine functions and principal component based approach (PCA) were also compared. However, given the loss of power caused by low minor allele frequencies (MAF), we conducted an extension work on PCA and used a new method called weighted PCA (wPCA). Comparative analysis was performed for weighted principal component analysis (wPCA), logistic kernel machine based test (LKM) and principal component analysis (PCA) based on SNP set in the case of different minor allele frequencies (MAF) and linkage disequilibrium (LD) structures. We also applied the three methods to analyze two SNP sets extracted from a real GWAS dataset of non-small cell lung cancer in Han Chinese population. Simulation results show that when the MAF of the causal SNP is low, weighted principal component and weighted IBS are more powerful than PCA and other kernel machine functions at different LD structures and different numbers of causal SNPs. Application of the three methods to a real GWAS dataset indicates that wPCA and wIBS have better performance than the linear kernel, IBS kernel and PCA.
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PMID:Weighted SNP set analysis in genome-wide association study. 2409 41

Established in 2008, the Patient-Reported Outcome (PRO) Consortium is a collaboration among the US Food and Drug Administration's Center for Drug Evaluation and Research, the Critical Path Institute, the pharmaceutical/biotechnology industry, and other stakeholders. The purpose of the consortium is to qualify PRO instruments through the Center for Drug Evaluation and Research's drug development tool qualification process for use as clinical trial endpoints to support drug approval and product labeling claims. The PRO Consortium has made notable progress toward collaborative development of PRO instruments in the following areas: asthma, mild cognitive impairment, depression, functional dyspepsia, irritable bowel syndrome, non-small cell lung cancer, and rheumatoid arthritis. This progress has come with considerable challenges, including navigating a new and evolving regulatory initiative, gaining consensus on key issues, and maintaining communication and engagement in a precompetitive environment. The purpose of this paper is to describe some of the challenges and lessons learned since the creation of the PRO Consortium in hopes that this information may provide direction and insight for similar collaborations.
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PMID:The Patient-Reported Outcome (PRO) Consortium: Lessons Learned Along the Path to PRO Instrument Qualification. 3022 53