Population based linkage disequilibrium mapping of QTL: An application to simulated data in an isolated population

Despite successes in mapping and cloning genes involved in rare Mendelian d iseases, genetic dissection of quantitative traits into single Mendelian fa ctors still remains a challenging task. As the dense map of single nucleoti de polymorphism (SNP) markers becomes available in the near future, linkage disequilibrium. (LD) mapping will become one of major tools for mapping an d identifying quantitative trait loci (QTL). In this report, we present a p opulation-based linkage disequilibrium. mapping of QTL. This method unifies the analysis of mapping QTL in humans and in model organisms and can be us ed for randomly sampled individuals. The proposed method is applied to sear ch for polymorphism sites within the candidate genes 2 and 6, which influen ce quantitative traits Q1 and Q2 or Q5, in a simulated data set in an isola ted population. (C) 2001 Wiley-Liss, Inc.