The approach is illustrated in Figure 1. In the figure, all individuals have been genotyped for a set of genetic markers are indicated in red; a subset of individuals in the top two generations has been genotyped at additional markers indicated in black (Panel A). Genotypes for the red markers, available in all individuals, can be used to infer the segregation of haplotypes through the family (Panel B). Finally, most of the missing genotypes for individuals in the bottom generation can be inferred by comparing the haplotypes they inherited with copies of the same haplotypes that are “identical-by-descent” and present in other individuals in the family (Panel C).
