Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) 22q11.2 deletion syndrome ?
    ### Response:
    22q11.2 deletion syndrome is a spectrum disorder that includes conditions formerly called DiGeorge syndrome; velocardiofacial syndrome; conotruncal anomaly face syndrome; cases of Opitz G/BBB syndrome; and Cayler cardiofacial syndrome. The features and severity can vary greatly among affected people.
    