The Williams Region is flanked by 3 segmental duplication (SD) blocks which mediate a recurrent deletion causing disease. We want to investigate the structure of these SDs and learn how these SDs differ between individuals. Next we want to study the evolution of these region in great ape genomes and assess which haplotypes exist in individuals throughout the world by using the public PanGenome resource. We want to see if we can find predisposing haplotypes for disease.