Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Achondroplasia ?
    ### Response:
    What causes achondroplasia? Achondroplasia is caused by mutations in the FGFR3 gene. This gene provides instructions for making a protein that is involved in the development and maintenance of bone and brain tissue. Two specific mutations in the FGFR3 gene are responsible for almost all cases of achondroplasia.
    