Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Lujan syndrome ?
    ### Response:
    Lujan syndrome is a condition characterized by intellectual disability, behavioral problems, and certain physical features. It occurs almost exclusively in males.  The intellectual disability associated with Lujan syndrome is usually mild to moderate. Behavioral problems can include hyperactivity, aggressiveness, extreme shyness, and excessive attention-seeking.
    