When you receive your genetic results and start researching the connection between your DNA and nutrition, MTHFR is probably a gene that you will hear a lot about. MTHFR, or methylene tetrahydrofolate reductase, is the name of the gene and corresponding enzyme involved in folate metabolism and DNA methylation (a process which adds methyl groups to a DNA molecule to control activity of the gene). The MTHFR enzyme is one of the main regulatory enzymes of homocysteine metabolism and works by converting homocysteine to methionine. Homocysteine and methionine are both amino acids (building blocks of protein) that are found in meat, fish, and dairy products. Homocysteine is also a breakdown product of amino acid metabolism, and elevated levels are thought to increase the risk of heart attacks and strokes. There are also some studies linking higher homocysteine levels to Alzheimer’s disease and cancer. It is thus important for the MTHFR enzyme to function well so that homocysteine levels do not accumulate and are converted to the safer methionine form.
The MTHFR gene is responsible for making a functional MTHFR enzyme. If the MTHFR gene is slightly altered, the MTHFR enzyme’s shape becomes distorted. Enzyme function depends a lot on shape. It is like the grooves on a key. If the grooves on a key are slightly different than the lock, the key may fit and turn the lock a little but it does not unlock the door. The genetic code of the MTHFR enzyme must be perfect in order for it to function properly. A dysfunctional MTHFR enzyme may lead to various health problems.
The MTHFR enzyme helps convert folate and folic acid into an active form that the body can use. Folate, also known as B9, refers to a group of B vitamins and is found naturally in foods. Spinach and other leafy greens, broccoli, edamame, avocadoes, oranges, and legumes are natural sources of folate. On the other hand, folic acid is a synthetic compound found in supplements and fortified foods, e.g. fortified flour in breads, cereals, and pasta. If you do not have a fully functioning form of the MTHFR enzyme, it is important that you take a supplement containing the activated form of folate as your body’s ability to synthesize this is impaired.
Having one mutated MTHFR copy (heterozygous) is associated with a decrease in enzyme function, but having two copies (homozygous) decreases enzyme function even more. This can lead to impaired folate levels, higher levels of homocysteine in the blood, and an increased risk of certain health problems. The most common gene variations are found at position 677 and/or position 1298 on the MTHFR gene. Depending on the variation, individual enzyme efficiency can drop to between 30-70% of normal levels. This means that some people might need more folate in their diets, especially a particular type of activated folate, called L-methylfolate or 5-MTHF.
Nutrigenetics Specialists offers a number of packages that address the MTHFR gene and more. We also have a dietary supplement package for 23andme users that focuses on 14 of the most commonly researched genes, including MTHFR 677 and 1298, which allows us to recommend the best supplements to include based on your individual genetic profile.