Below is an instruction from Human. Write a response.
    ### Instruction:
    How many people are affected by Opitz G/BBB syndrome ?
    ### Response:
    X-linked Opitz G/BBB syndrome is thought to affect 1 in 10,000 to 50,000 males, although it is likely that this condition is underdiagnosed.  The incidence of autosomal dominant Opitz G/BBB syndrome is unknown. It is part of a larger condition known as 22q11.
    