MTHFR C677T and A1298C: Explained In Plain English

https://www.dietvsdisease.org/mthfr-c677t-a1298c-mutation/

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Which MTHFR Mutation Is A Problem?

Heterozygous MTHFR mutations seem to have only minor influences on enzyme activity and health.

Heterozygous A1298C is thought to be of minor consequence (if any), while heterozygous C677T may affect folate metabolism by up to 35% (3, 11).

MTHFR mutations that have the greatest influence on health are:

• Homozygous A1298C (C1298C) and homozygous C677T (T677T)
• Compound heterozgous A1298C + C677T

Compound heterozgous is considered the most severe or "at risk", but it is thought that homozygous mutations can inhibit MTHFR enyzme function by up to a whopping 70% (11).

Remember that MTHFR mutations don't directly make you unwell. But they may cause an exaggerated response to poor diet or lifestyle choices that others can "get away with".

This is why dietary considerations are fundamental for certain MTHFR mutations.

As the saying goes, "Genes load the gun, environment pulls the trigger."