Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Dihydropyrimidine dehydrogenase deficiency ?
    ### Response:
    Dihydropyrimidine dehydrogenase (DPD) deficiency is a condition in which the body cannot break down the nucleotides thymine and uracil. DPD deficiency can have a wide range of severity; some individuals may have various neurological problems, while others have no signs and symptoms.
    