Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: Simultaneous fine mapping of closely linked epistatic quantitative trait loci using combined linkage | Genet. Sel. Evol. 40 2008 265-278 Available online at INRA EDP Sciences 2008 DOI gse 2008002 Original article Simultaneous fine mapping of closely linked epistatic quantitative trait loci using combined linkage disequilibrium and linkage with a general pedigree Sang Hong LEE Julius . VAN DER WERF The Institute for Genetics and Bioinformatics School of Rural Science and Agriculture University of New England Armidale NSW 2351 Australia Received 21 June 2007 accepted 21 September 2007 Abstract - Causal mutations and their intra- and inter-locus interactions play a critical role in complex trait variation. It is often not easy to detect epistatic quantitative trait loci QTL due to complicated population structure requirements for detecting epistatic effects in linkage analysis studies and due to main effects often being hidden by interaction effects. Mapping their positions is even harder when they are closely linked. The data structure requirement may be overcome when information on linkage disequilibrium is used. We present an approach using a mixed linear model nested in an empirical Bayesian approach which simultaneously takes into account additive dominance and epistatic effects due to multiple QTL. The covariance structure used in the mixed linear model is based on combined linkage disequilibrium and linkage information. In a simulation study where there are complex epistatic interactions between QTL it is possible to simultaneously map interacting QTL into a small region using the proposed approach. The estimated variance components are accurate and less biased with the proposed approach compared with traditional models. fine-mapping multiple QTL epistasis dominance reversible jump MCMC 1. INTRODUCTION Phenotypic variation in complex traits may involve the action of many causal genes and their intra- dominance and inter-locus interaction epistasis in addition to environmental factors. Multiple interacting QTL may play a critical .
