In a similar manner, the neuropsychiatric phenotype may be affected by the deletion of PIK4CA and SNAP29 from the distal region which have been demonstrated to be associated with schizophrenia[40-43], and not by the putative schizophrenia genes PRODH, COMT, DGCR8 and ZDHHC8. Another genetic mechanism that may affect the phenotype involves control elements in the deleted region that act by cis mechanisms on the expression of the non-deleted candidate genes as in the dosage-sensitive interaction between Tbx1and Crkl in mice[44]. Here, COMT is linked to schizophrenia.