rs121918243
A SNP in the MMACHC gene on chromosome 1. Its most notable genotype is A;A: methylmalonic aciduria, cblC type
- Gene
- MMACHC
- Location
- Chr 145,508,848 (GRCh38)
- Highest magnitude
- 8.0Very important
- Tested on
- Not on consumer chips
Genotypes
As shown in 23andMe and AncestryDNA files.
- A;AMost notableBadmethylmalonic aciduria, cblC type
- A;GBadcarrier of a methylmalonic aciduria allele
- G;GGoodcommon in clinvar
On SNPedia: (A;A), (A;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.
Related
Other MMACHC SNPs
- rs121918240C;Cmethylmalonic aciduria, cblC typeVery important
- rs121918241T;Tmethylmalonic aciduria, cblC typeVery important
- rs121918242T;Tmethylmalonic aciduria, cblC typeVery important
- rs370596113T;Tmethylmalonic aciduria, cblC typeVery important
- rs398124292A;Amethylmalonic aciduria, cblC typeVery important
- rs398124293-;-methylmalonic aciduria, cblC typeVery important
- rs398124295A;Amethylmalonic aciduria, cblC typeVery important
- rs398124296-;-methylmalonic aciduria, cblC typeVery important
Notes
From SNPedia
Notes
A;A
This genotype represents two defective MMACHC gene alleles, leading to an inborn error of metabolism known as methylmalonic aciduria, cblC type.
Source and license
Adapted from rs121918243 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.
SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.