Frequency of MTHFR Polymorphisms

30-40% of Americans are found to have either a single or double polymorphism of either C677T or A1298C.

  • There is ethnic variability in the frequency of the T allel-frequency in Mediterranean/Hispanics>Caucasians>Africans/African-Americans (Worldwide distribution of a common methylenetetrahydrofolate reductase mutation. Am J Hum Genet 62 (5): 1258-60)
  • Higher frequency in chronic disease: Autoimmune diseases, diseases of the gut, Fibromyalgia, Chronic Fatigue, Chronic Retroviruses, Cancer, Hormone dysregulation, Mood issues, Cardiometabolic patients.

C667Tpolymorphtandem-baucom-institute

  • There is a mutation from cytosine to adenine at position 677 within the gene.
  • Possible genotypes?
  • 677-CC, CT, or TT
  • CC-homozygous normal
  • About 45% of the population
  • No increased risk associate
  • CT-on variant copy
  • About 45% of the population
  • Some reduced enzymatic activity, alone not associated with increased risk
  • TT-two variant copies
  • About 10% of the population
  • Increased risk for elevated homocysteine level and associated complications