ABSTRACT
The concept of genetic distance has allowed the development of sophisticated statistical approaches for genetic mapping. To estimate the position of a disease locus on a chromosome, one generally collects families in which the disease segregates. Localization of a gene underlying a recessive or dominant trait is relatively straightforward. However, there may still be complications that need to be mastered. The basic idea is that pedigree data are collected, in which a particular heritable disease occurs, and family members are genotyped for a large number of genetic markers, which are known to reside along each of the human chromosomes. Linkage analysis methods are generally divided into two groups, parametric and nonparametric methods. In genome screens, lod scores are computed at each marker locus and local peaks of the resulting lod score curve are potentially indicative of the location of a susceptibility locus.
