ABSTRACT
This chapter introduces the quantitative genetics concepts of quantitative trait inheritance. Quantitative Trait Locus (QTL) mapping is a combination of qualitative linkage analysis and quantitative genetics analysis. The chapter describes a practical single-locus or single-QTL model and a multiple-locus model for quantitative traits. In a quantitative genetic model, it is not always necessary to know the genotypes of the individuals in a population. However, the genotypes are needed to estimate parameters of a genetic model. A genetic model for a quantitative trait is usually defined in terms of number of genes, gene effects and frequencies, relationship among the genes and relationship between environment and gene action. The purpose of QTL mapping is to infer the QTL genotypes in order to estimate the QTL effects and locations from association with known genetic markers.
