Chromosome 22 SMC from patient 3. A. G-banded normal chromosome 22 homologues and SMC (arrow). B. Array CGH plot showing gains of both proximal and distal 22q, but not the intervening region between 22q11.21 and q13.31. C. FISH using BACs RP11-1037C4 from 22q11.1 (red signal) and RP11-676E13 from 22q13.33 (green signal) shows signal from both BACs on the SMC (arrow), as well as both normal homologues on chromosome 22 (arrowheads). D. FISH using BACs CTD-2593O4 from 22q11.21 (red) and RP11-676E13 (green) again confirms the presence of both proximal and distal 22q in the SMC (arrow).