|Summary||MTHFR polymorphisms affecting homocysteine|
You have a combination of 2 SNP variations in MTHFR which influence homocysteine levels. This is found in ~20% of people. 0.08% of people had a double copy of a mutation in one of the SNPs, and a single mutation in the other. [PMID 15834246] .
gs193 indicates double mutations in both snps, and people with this are believed to be critically impacted, however several promethease users have self reported this genotype with no apparent consequences.
MTHFR mutation frequencies in a sample of 37,000 individuals:
- 677CT/1298AA 22.8% - 1 heterozygous mutation
- 677CC/1298CA 20.8% - 1 heterozygous mutation
- 677CT/1298CA 19.8% - 2 heterozygous mutations (compound heterozygous) gs192
- 677CC/1298AA 15.3% - no mutations
- 677TT/1298AA 12.2% - 1 homozygous mutation
- 677CC/1298CC 08.8% - 1 homozygous mutation
- 677TT/1298CA 00.05% - 1 heterozygous and 1 homozygous mutation gs192
- 677CT/1298CC 00.03% - 1 heterozygous and 1 homozygous mutation gs192
- 677TT/1298CC none - 2 homozygous mutations (compound homozygous) gs193
Note that both snps have minus orientation.