Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to biotinidase deficiency ?
    ### Response:
    Mutations in the BTD gene cause biotinidase deficiency. The BTD gene provides instructions for making an enzyme called biotinidase. This enzyme recycles biotin, a B vitamin found in foods such as liver, egg yolks, and milk. Biotinidase removes biotin that is bound to proteins in food, leaving the vitamin in its free (unbound) state.
    