Many characters of biological interest and economical importance that are not inherited in a simple Mendelian fashion vary in a discrete form. These traits are called complex discrete traits. A complex discrete trait is presumably controlled by several genes, and characteristic of the trait is modified by environmental effects. Although methods of mapping QTL for continuous quantitative characters have been well developed, such methods for discrete characters are not available yet. So many non-linear methods were developed under the framework of the generalized linear model. In this paper, we reviewed the recent progress and improvement of the methods for QTL mapping in this field.
[Methodology of QTL's linkage analysis for discrete traits controlled by polygenes] Publishing Authors By Initials