These factors include. 1  Living at high latitudes (closer to the polar regions), particularly during winter months. 2  Air quality conditions: high levels of air pollution. 3  Weather conditions: dense cloud covering. 4  The degree to which clothing covers the skin. 5  Use of sunscreen. 6  Skin pigmentation: darker skin types.
A few cases of severe homocysteinemia have been due to rare MTHFR gene mutations (sometimes in combination with a second common MTHFR gene mutation). Symptoms in these patients varied greatly but often involved pronounced neurological symptoms and blood vessel disease.
When itâs all working right (and it can be for awhile even with the mutation), the MTHFR gene begins a multi-step chemical breakdown process, aka methylation, which is like this: 1  The MTHFR gene produces the MTHFR enzyme. 5-methyltetrahydrofolate helps convert the amino acid homocysteine down to another essential amino acid, methionine, which is used by your body to make proteins, utilize antioxidants, and to assist your liver to process fats.