Parameter estimation for robust HMM analysis of ChIP-chip data

<p>Abstract</p> <p>Background</p> <p>Tiling arrays are an important tool for the study of transcriptional activity, protein-DNA interactions and chromatin structure on a genome-wide scale at high resolution. Although hidden Markov models have been used successfully to a...

Full description

Bibliographic Details
Main Authors: Humburg Peter, Bulger David, Stone Glenn
Format: Article
Language:English
Published: BMC 2008-08-01
Series:BMC Bioinformatics
Online Access:http://www.biomedcentral.com/1471-2105/9/343
_version_ 1811297387119902720
author Humburg Peter
Bulger David
Stone Glenn
author_facet Humburg Peter
Bulger David
Stone Glenn
author_sort Humburg Peter
collection DOAJ
description <p>Abstract</p> <p>Background</p> <p>Tiling arrays are an important tool for the study of transcriptional activity, protein-DNA interactions and chromatin structure on a genome-wide scale at high resolution. Although hidden Markov models have been used successfully to analyse tiling array data, parameter estimation for these models is typically <it>ad hoc</it>. Especially in the context of ChIP-chip experiments, no standard procedures exist to obtain parameter estimates from the data. Common methods for the calculation of maximum likelihood estimates such as the Baum-Welch algorithm or Viterbi training are rarely applied in the context of tiling array analysis.</p> <p>Results</p> <p>Here we develop a hidden Markov model for the analysis of chromatin structure ChIP-chip tiling array data, using <it>t </it>emission distributions to increase robustness towards outliers. Maximum likelihood estimates are used for all model parameters. Two different approaches to parameter estimation are investigated and combined into an efficient procedure.</p> <p>Conclusion</p> <p>We illustrate an efficient parameter estimation procedure that can be used for HMM based methods in general and leads to a clear increase in performance when compared to the use of <it>ad hoc </it>estimates. The resulting hidden Markov model outperforms established methods like TileMap in the context of histone modification studies.</p>
first_indexed 2024-04-13T06:03:28Z
format Article
id doaj.art-a141bfba397841dfa26d97476e1ba5ac
institution Directory Open Access Journal
issn 1471-2105
language English
last_indexed 2024-04-13T06:03:28Z
publishDate 2008-08-01
publisher BMC
record_format Article
series BMC Bioinformatics
spelling doaj.art-a141bfba397841dfa26d97476e1ba5ac2022-12-22T02:59:21ZengBMCBMC Bioinformatics1471-21052008-08-019134310.1186/1471-2105-9-343Parameter estimation for robust HMM analysis of ChIP-chip dataHumburg PeterBulger DavidStone Glenn<p>Abstract</p> <p>Background</p> <p>Tiling arrays are an important tool for the study of transcriptional activity, protein-DNA interactions and chromatin structure on a genome-wide scale at high resolution. Although hidden Markov models have been used successfully to analyse tiling array data, parameter estimation for these models is typically <it>ad hoc</it>. Especially in the context of ChIP-chip experiments, no standard procedures exist to obtain parameter estimates from the data. Common methods for the calculation of maximum likelihood estimates such as the Baum-Welch algorithm or Viterbi training are rarely applied in the context of tiling array analysis.</p> <p>Results</p> <p>Here we develop a hidden Markov model for the analysis of chromatin structure ChIP-chip tiling array data, using <it>t </it>emission distributions to increase robustness towards outliers. Maximum likelihood estimates are used for all model parameters. Two different approaches to parameter estimation are investigated and combined into an efficient procedure.</p> <p>Conclusion</p> <p>We illustrate an efficient parameter estimation procedure that can be used for HMM based methods in general and leads to a clear increase in performance when compared to the use of <it>ad hoc </it>estimates. The resulting hidden Markov model outperforms established methods like TileMap in the context of histone modification studies.</p>http://www.biomedcentral.com/1471-2105/9/343
spellingShingle Humburg Peter
Bulger David
Stone Glenn
Parameter estimation for robust HMM analysis of ChIP-chip data
BMC Bioinformatics
title Parameter estimation for robust HMM analysis of ChIP-chip data
title_full Parameter estimation for robust HMM analysis of ChIP-chip data
title_fullStr Parameter estimation for robust HMM analysis of ChIP-chip data
title_full_unstemmed Parameter estimation for robust HMM analysis of ChIP-chip data
title_short Parameter estimation for robust HMM analysis of ChIP-chip data
title_sort parameter estimation for robust hmm analysis of chip chip data
url http://www.biomedcentral.com/1471-2105/9/343
work_keys_str_mv AT humburgpeter parameterestimationforrobusthmmanalysisofchipchipdata
AT bulgerdavid parameterestimationforrobusthmmanalysisofchipchipdata
AT stoneglenn parameterestimationforrobusthmmanalysisofchipchipdata