Genome-wide expression quantitative trait loci analysis in asthmaBossé, YohanCurrent Opinion in Allergy & Clinical Immunology: October 2013 - Volume 13 - Issue 5 - p 487–494 doi: 10.1097/ACI.0b013e328364e951 GENETICS AND EPIDEMIOLOGY: Edited by Catherine Laprise and Emmanuelle Bouzigon Abstract Author Information Purpose of review: Expression quantitative trait loci (eQTL) mapping studies are the next most important step in genomics to identify susceptibility genes and molecular pathways involved in human diseases following the completion of genome-wide association studies (GWAS). This article reviews the emerging concepts in genetics of gene expression and the empirical value of eQTL mapping to refine GWAS asthma susceptibility loci. Recent findings: eQTL mapping studies were paramount to reveal the cis and trans control of gene expression, the cell type and tissue specificity of eQTLs, and the pleiotropic nature of eQTL single nucleotide polymorphisms. A small number of eQTL studies were recently performed in tissues and cell types that are relevant for asthma and are used to interpret the biology underpinning GWAS loci including the most robust asthma susceptibility locus on 17q21. Summary: The full potential of eQTL mapping studies is just starting to be revealed. Imminent progress is expected owing to the accelerating advances in sequencing technologies to map genetic variants and transcriptomes as well as the development of bioinformatics and computational algorithms to exploit integrative genomic approaches. A short-term challenge in the field of asthma is the creation of well powered eQTL datasets testing gene expression and other molecular phenotypes in disease-relevant tissues. aCentre de recherche de l’Institut universitaire de cardiologie et de pneumologie de Québec bDepartment of Molecular Medicine, Laval University, Québec, Canada Correspondence to Yohan Bossé, PhD, Associate Professor, Laval University, Institut universitaire de cardiologie et de pneumologie de Québec, Pavillon Marguerite-d’Youville, Y4190, 2725, chemin Sainte-Foy, Québec (Québec), G1V 4G5, Canada. Tel: +1 418 656 8711 x3725; fax: +1 418 656 4602; e-mail: firstname.lastname@example.org Copyright © 2013 Wolters Kluwer Health, Inc. All rights reserved.