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Homocysteinemia due to MTHFR deficiency

Other Names for this Disease
  • 5,10 alpha methylenetetrahydro-folate reductase deficiency
  • 5,10-alpha-methylenetetrahydro-folate reductase deficiency
  • Homocysteinemia due to methylenetetrahydro-folate reductase deficiency
  • Homocysteinuria due to methylenetetrahydro-folate reductase deficiency
  • Homocysteinuria due to MTHFR deficiency
More Names
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What are the signs and symptoms of homocysteinemia due to MTHFR deficiency?

Symptoms of MTHFR deficiency vary from no symptoms to severe neurologic and blood vessel disease. Health problems tend not to be related to whether someone has a MTHFR gene mutation or even a MTHFR enzyme deficiency, but whether the deficiency is leading to elevated levels of homocysteine in the blood or urine.[1] Elevated levels of homocysteine in the blood can damage the lining of the arteries, which increases the risk of heart disease, including coronary heart disease, and stroke in adults. However, there are many other factors that play a part in determining a person’s risk of heart disease and stroke.[2] And many people with a homocysteinemia may never have any symptoms or adverse complications.[2]

High homocysteine levels in the blood may also increase the risk of preeclampsia, miscarriage, and blood clots. In general, mild to moderate homocysteinemia has been associated with an increase risk developing blood clots in the veins often in the lower leg or calf, which can travel to the lung (i.e., pulmonary embolism). [3]
Last updated: 7/20/2011

  1. Homocystinuria. Genetics Home Reference (GHR). 2008; Accessed 3/16/2011.
  2. MTHFR. Genetics Home Reference (GHR). Februrary 2011; Accessed 7/14/2011.
  3. Homocysteine. American Academy of Family Physicians. 2006; Accessed 5/13/2009.