Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Primary Hyperparathyroidism ?
    ### Response:
    The parathyroid glands are four pea-sized glands located on or near the thyroid gland in the neck. Occasionally, a person is born with one or more of the parathyroid glands in another location. For example, a gland may be embedded in the thyroid, in the thymusan immune system organ located in the chestor elsewhere around this area.
    