Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Linear porokeratosis ?
    ### Response:
    Linear porokeratosis is a skin condition that most often begins in infancy or early childhood, but it can occur at any age.  The main feature of this condition is the development of reddish brown, slightly raised markings on the skin arranged in lines or streaks on one side of the body.
    