Below is an instruction from Human. Write a response.
    ### Instruction:
    How many people are affected by beta-ureidopropionase deficiency ?
    ### Response:
    The prevalence of beta-ureidopropionase deficiency is unknown. A small number of affected individuals from populations around the world have been described in the medical literature. In Japan, the prevalence of beta-ureidopropionase deficiency has been estimated as 1 in 6,000 people.
    