Unpublished conference/Abstract (Scientific congresses and symposiums)
An Efficient Algorithm to Perform Multiple Testing in Epistasis Screening
Van Lishout, François; Cattaert, Tom; Mahachie John, Jestinah et al.
2011Benelux Bioinformatics Conference 2011
 

Files


Full Text
BBC2011VanLishoutAbstract.pdf
Publisher postprint (48.45 kB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Abstract :
[en] Background: Research in epistasis or gene-gene interaction detection for human complex traits has grown exponentially over the last few years. It has been marked by promising methodological developments, improved translation efforts of statistical epistasis to biological epistasis and attempts to integrate different omics information sources into the epistasis screening to enhance power. The quest for gene-gene interactions poses severe multiple-testing problems. In this context, the maxT algorithm is one technique to control the false-positive rate. However, the memory needed by this algorithm rises linearly with the amount of hypothesis tests. In main-effects detection, this is not a problem since the memory required is thus proportional to the number of SNPs. In contrast, gene-gene interaction studies will require a memory proportional to the squared amount of SNPs. A genome wide epistasis would therefore require terabytes of memory. Hence, cache problems are likely to occur, increasing the computation time. Methods: In this work we present a new version of maxT, requiring an amount of memory independent from the number of genetic effects to be investigated. This algorithm was implemented in C++ in our epistasis screening software MB-MDR-2.6.2 and compared to MB-MDR's first implementation as an R-package (Calle et al., Bioinformatics 2010). We evaluate the new implementation in terms of memory efficiency and speed using simulated data. The software is illustrated on real-life data for Crohn's disease. Results: The sequential version of MBMDR-2.6.2 is approximately 5,500 times faster than its R counterparts. The parallel version (tested on a cluster composed of 14 blades, containing each 4 quad-cores Intel Xeon CPU E5520@2.27 GHz) is approximately 900,000 times faster than the latter, for results of the same quality on the simulated data. It analyses all gene-gene interactions of a dataset of 100,000 SNPs typed on 1000 individuals within 4 days. Our program found 14 SNP-SNP interactions with a p-value less than 0.05 on the real-life Crohn’s disease data. Conclusions: Our software is able to solve large-scale SNP-SNP interactions problems within a few days, without using much memory. A new implementation to reach genome wide epistasis screening is under construction. In the context of Crohn's disease, MBMDR-2.6.2 found signal in regions well known in the field and our results could be explained from a biological point of view. This demonstrates the power of our software to find relevant phenotype-genotype associations.
Disciplines :
Computer science
Author, co-author :
Van Lishout, François ;  Université de Liège - ULiège > Dép. d'électric., électron. et informat. (Inst.Montefiore) > Bioinformatique
Cattaert, Tom ;  Université de Liège - ULiège > Dép. d'électric., électron. et informat. (Inst.Montefiore) > Bioinformatique
Mahachie John, Jestinah ;  Université de Liège - ULiège > Dép. d'électric., électron. et informat. (Inst.Montefiore) > Bioinformatique
Gusareva, Elena ;  Université de Liège - ULiège > Dép. d'électric., électron. et informat. (Inst.Montefiore) > Bioinformatique
Urrea, Victor
Cleynen, Isabelle
Theatre, Emilie ;  Université de Liège - ULiège > Département de productions animales > GIGA-R : Génomique animale
Charloteaux, Benoît ;  Université de Liège - ULiège > Département de productions animales > GIGA-R : Génomique animale
Kvasz, Alexandre
Calle, M. Luz
Wehenkel, Louis  ;  Université de Liège - ULiège > Dép. d'électric., électron. et informat. (Inst.Montefiore) > Systèmes et modélisation
Van Steen, Kristel  ;  Université de Liège - ULiège > Dép. d'électric., électron. et informat. (Inst.Montefiore) > Bioinformatique
Language :
English
Title :
An Efficient Algorithm to Perform Multiple Testing in Epistasis Screening
Publication date :
13 December 2011
Event name :
Benelux Bioinformatics Conference 2011
Event organizer :
The Netherlands Bioinformatics Centre
Event place :
Luxembourg, Luxembourg
Event date :
12 - 13.12.2011
Audience :
International
Available on ORBi :
since 23 January 2012

Statistics


Number of views
121 (26 by ULiège)
Number of downloads
157 (2 by ULiège)

Bibliography


Similar publications



Contact ORBi