Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to Parkes Weber syndrome ?
    ### Response:
    Some cases of Parkes Weber syndrome result from mutations in the RASA1 gene. When the condition is caused by RASA1 gene mutations, affected individuals usually have multiple capillary malformations. People with Parkes Weber syndrome who do not have multiple capillary malformations are unlikely to have mutations in the RASA1 gene; in these cases, the cause of the condition is often unknown.
    