MTHFR

The MTHFR gene gives your body instructions to make an enzyme that plays a big role in a process called methylation. Methylation is like your body’s switchboard—it helps turn certain processes on or off. This includes things like repairing your DNA, controlling gene activity, detoxifying harmful substances, processing nutrients, and supporting your immune system.

The enzyme made by the MTHFR gene is key for helping your body run smoothly. It’s involved in fixing DNA, controlling which genes are active, and managing many other important functions.

The two most common changes in the MTHFR gene that doctors and researchers look at are C677T and A1298C. The letters and numbers refer to a tiny change in your DNA—called a SNP (pronounced “snip”).

The C677T mutation affects the MTHFR gene, making its enzyme less effective. This can lead to higher homocysteine levels and lower folate use, which may raise the risk of heart disease and other health issues. One copy = ~35% less enzyme activity. Two copies = ~70% less activity. It can also affect detoxification, DNA repair, and mental health.

The A1298C mutation affects how the MTHFR gene helps make BH4, a compound important for detoxifying ammonia and making neurotransmitters. One copy = ~30% reduced enzyme function. Two copies may cause greater impact. Unlike C677T, it usually doesn't raise homocysteine, but it can affect mood, mental health, and detoxification.