While the role of HDAC4 is quite well established, for other genes the involvement is merely suggested by the overlapping deleted region in reported cases: GPC1, PDC1, STK25, and GPR35 are candidate genes for facial dysmorphism and brachydactyly, FARP2- for facial dysmorphism, brachydactyly and behavioral disorders, TWIST2- candidate genes for brachydactyly, behavioral disorders, various skeletal defects, and cardiac anomalies, CAPN10, HDLBP, SH3BP4, AGAP1-overweightness or obesity, D2HGDH-possible responsible seizures, and KIF1A-behavioral disorders [6,7,10,11,12,13]. This evidence concerns the gene TWIST2 and Atypical behavior.