Evidence map›Paper›PMID 18410691›Full record

ArticleBMC bioinformatics2008

A probe-treatment-reference (PTR) model for the analysis of oligonucleotide expression microarrays.

Huanying Ge, Chao Cheng, Lei M Li

Abstract read
In one paragraph

Article in BMC bioinformatics, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers.

0numbers the graph read from it
0cells of the map it votes in
8citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

Who cites it

8 citing papers in PubMed.

  1. Observational
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4 · The record

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5 · Who and what money

Authors and funding

3 authors.

Huanying GeMolecular and Computational Biology, Department of Biology Sciences, University of Southern California, Los Angeles, CA 90089-2910, USA. hge@usc.edu
Chao Cheng
Lei M Li

Funding

Detection and Understanding of Expression DifferentiatioR01GM075308 · NIGMS · UNIVERSITY OF SOUTHERN CALIFORNIA · PI LI, LEI · 2005 to 2009
$1.1M
NIGMS NIH HHS R01 GM075308NIGMS NIH HHS R01 GM75308-01
6 · The paper itself

Abstract

backgroundMicroarray pre-processing usually consists of normalization and summarization. Normalization aims to remove non-biological variations across different arrays. The normalization algorithms generally require the specification of reference and target arrays. The issue of reference selection has not been fully addressed. Summarization aims to estimate the transcript abundance from normalized intensities. In this paper, we consider normalization and summarization jointly by a new strategy of reference selection.

resultsWe propose a Probe-Treatment-Reference (PTR) model to streamline normalization and summarization by allowing multiple references. We estimate parameters in the model by the Least Absolute Deviations (LAD) approach and implement the computation by median polishing. We show that the LAD estimator is robust in the sense that it has bounded influence in the three-factor PTR model. This model fitting, implicitly, defines an "optimal reference" for each probe-set. We evaluate the effectiveness of the PTR method by two Affymetrix spike-in data sets. Our method reduces the variations of non-differentially expressed genes and thereby increases the detection power of differentially expressed genes.

conclusionOur results indicate that the reference effect is important and should be considered in microarray pre-processing. The proposed PTR method is a general framework to deal with the issue of reference selection and can readily be applied to existing normalization algorithms such as the invariant-set, sub-array and quantile method.

Indexed as

Models, GeneticAlgorithmsBase SequenceComputer SimulationDNA ProbesGene Expression ProfilingMolecular Sequence DataOligonucleotide Array Sequence AnalysisReference ValuesSequence AlignmentSequence Analysis, DNADNA Probes

Identifiers

PMID18410691
PMCPMC2375129

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.