rs1801133
rs1801133 is the common MTHFR Ala222Val change, often called C677T. On the GRCh38 forward strand, G is coding C/Ala222 and A is coding T/Val222. The coding T version makes a heat-sensitive enzyme with lower average activity. One small selected enzyme study found coding C/T and T/T group means near 65% and 30% of the coding C/C mean. Those percentages are not personal measurements. Genomic C and T are other unstudied alleles at this multiallelic site and are outside the reviewed map.
Traits rs1801133 reads
Gene
Reference databases
How Biome reads this
Biome's whole-genome test reads this from one saliva sample, alongside all 3.2 billion letters of your DNA.
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