Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Choroideremia ?
    ### Response:
    Choroideremia is a genetic condition that causes vision loss. This disorder typically affects males. The first symptom is usually impairment of night vision (night blindness), which can occur in childhood. People with this disorder also experience narrowing of the field of vision (tunnel vision) and decrease in the ability to see details (visual acuity).
    