A Comparison of Transcript-centric and Marker-centric Approaches for Mapping Expression Trait Loci

• Activity Number: 37
• Type: Invited
• Date/Time: Sunday, August 8, 2004 : 4:00 PM to 5:50 PM
• Sponsor: ENAR
• Author(s): Christina Kendziorski*+ and Meng Chen
• Companies: University of Wisconsin, Madison and University of Wisconsin, Madison
• Keywords: experimental design ; power calculations ; microarrays ; quantitative trait loci (QTL) mapping ; expression trait loci (ETL) mapping

Abstract

The development of statistical methods for mapping quantitative traits has received considerable attention. Effective methods now exist to account for different types of crosses or family structures, different kinds of phenotypes, the presence of multiple genes affecting the trait and their genetic interactions, and the multiple testing issues that arise from tests at many markers. A number of groups have recently applied these QTL methods to the problem of mapping mRNA abundance measurements by considering each individual transcript as a quantitiative trait. However, most QTL mapping methods were developed to address the case where a small number of traits (oftentimes, just one) are being mapped. In expression trait loci mapping, thousands of traits are considered simultaneously and the repeated application of individual tests is not the most efficient strategy. I will present an empirical Bayes modeling approach to enable ETL mapping. The inefficiency of the single trait method and the utility of the proposed method are demonstrated using microarray and genotype data from an F2 mouse cross in a study of diabetes.