Do you have a MTHFR mutation? Almost certainly, the answer is yes.
The DNA analysis tool Promethease lists 12 known SNPs (Single Nucleotide Polymorphisms - known mutations). Of those, it lists the percentage of wild types (non-mutated) for each SNP. They range from 39% to 89%.
You can use those figures to calculate the proportion of people that don’t have any mutations.
The chances of having a mutation in at least one of these 10 SNPs is…
1 - (0.5 x 0.44 x 0.39 x 0.46 x 0.49 x 0.62 x 0.69 x 0.69 x 0.76 x 0.89) = 0.996
That means that a mere 4 people out of 1000 do NOT have a MTHFR mutation.
So, next time somebody says they have a MTHFR mutation you can tell them that almost everybody does.