Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Muscular dystrophy, congenital, merosin-positive ?
    ### Response:
    The congenital muscle dystrophies are currently classified according to the genetic defects. Historically, congenital muscular dystrophies were classified in two broad groups: Classic CMD (which included the Merosin-deficient CMD and the Merosin-positive CMD) and the CMD with central nervous system (CNS) abnormalities (Fukuyama CMD, muscle-eye-brain disease and Walker-Warburg syndrome).
    