Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Branchiootorenal syndrome ?
    ### Response:
    Branchiootorenal syndrome is characterized by birth defects or anomalies of tissues in the neck, malformations of the external ear, hearing loss, and kidney malformations. Symptom and symptom severity can vary greatly from person to person. It can be caused by mutations in the EYA1, SIX1, or SIX5 genes.
    