COMT and 22q11.2 deletion syndrome: The array-CGH analysis determined that the 22q11.2 deletion included several genes, such as TBX1, COMT, and RTN4R. The TBX1 gene encodes a T-box transcription factor, and its haploinsufficiency is largely responsible for the physical malformations associated with 22q11.2 deletion syndrome, such as CHD and dysmorphisms [10,20].