Below is an instruction from Human. Write a response.
    ### Instruction:
    How many people are affected by X-linked dystonia-parkinsonism ?
    ### Response:
    X-linked dystonia-parkinsonism has been reported in more than 500 people of Filipino descent, although it is likely that many more Filipinos are affected. Most people with this condition can trace their mother's ancestry to the island of Panay in the Philippines.
    