The syndrome was first observed by Ann Smith et al. in 1986, when they described nine unrelated patients as having a new rare genetic disease [3] and showing a chromosomal deletion in the short arm of chromosome 17 in a portion of the 17p11.2 band, causing haploinsufficiency of the retinoic acid-induced 1 (RAI1) gene [3,4]. The gene discussed is RAI1; the disease is hereditary disease.