QTL mapping and genetic architecture of quantitative traits
by
Zhao-Bang Zeng
Departments of Statistics and Genetics, North Carolina State University, USA

Understanding and estimating the structure and parameters associated with the genetic architecture of quantitative traits is a major research focus in quantitative genetics. With the availability of a well-saturated genetic map of molecular markers, it is possible to identify a major part of the structure of the genetic architecture of quantitative traits and to estimate the associated parameters. Multiple interval mapping, which was recently developed for simultaneously mapping multiple quantitative trait loci (QTL), is well suited to the identification and estimation of the genetic architecture parameters, including the number, genomic positions, effects and interactions of significant QTL and their contribution to the genetic variance. Associated with the methodology development, computer software, called QTL Cartographer (http://statgen.ncsu.edu/qtlcart/cartographer.html), is also developed and freely distributed for QTL mapping data analysis. There are a number of challenging issues in this analysis, such as maximum likelihood analysis with multiple QTL, search and identification of QTL positions and interaction pattern, model selection criteria and practical implementation of the method. Many of these issues are discussed and real data analysis from Drosophila experiments are used to illustrate the potential power and advantages of the method for mapping multiple QTL and estimating the genetic architecture.

Date received: November 1, 2001