Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Birt-Hogg-Dub syndrome ?
    ### Response:
    Birt-Hogg-Dub syndrome is a rare disorder that affects the skin and lungs and increases the risk of certain types of tumors. Its signs and symptoms vary among affected individuals.  Birt-Hogg-Dub syndrome is characterized by multiple noncancerous (benign) skin tumors, particularly on the face, neck, and upper chest.
    