<prompt> Answer this question truthfullyWhat is the CATCH 22 mnemonic used to remember the features of a chromosome 22q11 microdeletion?  <response>: <reason> The CATCH 22 mnemonic is used to remember the features of a chromosome 22q11 microdeletion, which stands for Cleft palate, Abnormal facies, Thymic aplasia, Conotruncal abnormalities truncus arteriosus, tetralogy of Fallot, interrupted aortic arch, and Hypocalcemia lack of parathyroids. 