TOPICS: Chromosome, homologous recombination errors, Cri-du-chat syndrome, Williams syndrome, DiGeorge syndrome (velocardiofacial syndrome), deletion of a segment of the short arm of chromosome 5, deletion of a segment of the long arm of chromosome 7, elastin gene, deletion of a segment of the long arm of chromosome 22 (22q11), 3rd and 4th pharyngeal pouches, thymus, hypertelorism, elfin appearance, congenital heart disease, intellectual disability, epicanthal folds, thymic aplasia, cleft palate, immunodeficiency, absent thymic shadow
