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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 causes homocysteinemia due to MTHFR deficiency?

Homocysteinemia due to MTHFR deficiency is caused by mutations in the MTHFR gene, which provides the instructions for making an enzyme called MTHFR. MTHFR  is important for a chemical reaction in the body involving forms of the vitamin called folate.   A change or mutation in the MTHFR gene may result in an enzyme that doesn't work like it should. Once the MTHFR enzyme has finished its work on the folate, the folate is ready to be used in the body. One of its jobs it to process a chemical called homocysteine, changing it to methionine which is used for making proteins and other important compounds.[1] 

There are many different gene mutations that can occur in the MTHFR gene that can result in a MTHFR enzyme that is not working as it should. The most common MTHFR gene mutation is the C677T mutation.[1]
Last updated: 7/20/2011

  1. MTHFR. Genetics Home Reference (GHR). Februrary 2011; Accessed 7/14/2011.