Complex segregation analysis has been extended to apply to nuclear families and relatives outside the nuclear family that have led to its ascertainment. These individuals are referred to as pointers. The mixed model of Morton and MacLean has been modified to allow for a sex-linked major gene, mutation, and generational differences in multifactorial transmission for adults and children, respectively. The model and methods used in implementing it are described, as well as the rationale underlying this approach to analysis of pedigree data.
