Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the symptoms of MTHFR gene mutation ?
    ### Response:
    What are the signs and symptoms of MTHFR gene mutations? People with MTHFR gene mutations may develop elevated levels of homocysteine in their blood (homocysteinemia) or urine (homocystinuria). Risks for health effects vary depending on the levels of homocysteine.
    