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Criteria doesn't match?[edit]

I'm having difficulty understanding the description of gs231 given the criteria for this genoset. The included link is to an article regarding an individual who addressed reduced MTHFR activity by taking L-methylfolate (levomefolic acid) as well as a study calling for individuals with reduced MTHFR activity.

Yet the criteria for this genoset, (rs1801131(C;C), and rs1801133(C;C)) both indicate that C;C homozygotes comprise the "normal or good" variation associated with no reduced MTHFR activity. "Homozygous rs1801133(T;T) individuals have ~30% of the expected MTHFR enzyme activity, and rs1801133(C;T) heterozygotes have ~65% activity, compared to the most common genotype, rs1801133(C;C)." Also note, from DIY Genomics, "At nucleotide 1298 (rs1801131) of the MTHFR, there are two possibilities: A or C. 1298A (leading to a Glu at amino acid 429) is the most common while 1298C (leading to an Ala substitution at amino acid 429) is less common. 1298AA is the "normal" homozygous, 1298AC the heterozygous, and 1298CC the homozygous for the "variant". In studies of human recombinant MTHFR, the protein encoded by 1298C cannot be distinguished from 1298A in terms of activity, thermolability, FAD release, or the protective effect of 5-methyl-THF. The C mutation does not appear to affect the MTHFR protein. It does not result in thermolabile MTHFR and does not appear to affect homocysteine levels." Can someone explain the apparent discrepancy? Taurus (talk) 13:44, 30 March 2014 (UTC)

based on hapmap rs1801131

  • rs1801131(A;A) common in hapmap
  • rs1801131(A;C) mixed
  • rs1801131(C;C) rare in hapmap

rs1801133 1298 429

  • rs1801133(C;C) common in hapmap
  • rs1801133(C;T) mixed ~65% of the expected MTHFR enzyme activity
  • rs1801133(T;T) rare in hapmap ~30% of the expected MTHFR enzyme activity

So it seems the corrected criteria should be


I'm making that change now. --- cariaso 17:34, 30 March 2014 (UTC)

Great, thanks! Taurus (talk) 18:49, 30 March 2014 (UTC)