Each gene is duplicated twice in a child when they are born, one from each parent. MTHFR is the name of one of the thousands of genes that each individual carries two copies of. The gene produces the enzyme “methylenetetrahydrofolate reductase“. It converts dietary folate (vitamin B-9 or folic acid) into the physiologically active form L-methylfolate, which your cells need.
When folate or folic acid takes, cells convert it to L-methylfolate. It then continues its biological functions as efficiently as possible.
Unfortunately, many people have a slight mutation in the coding of their MTHFR gene in one or both copies. Depending on the context, a difference in a gene’s code referrs to a “mutation,” “variant,” or “polymorphism.”
The variation in the gene code determines the severity of this biological snag and if one or both copies of a faulty gene inherit.
Some of these code changes are more prevalent than others. The MTHFR gene has at least 40 different uncommon mutations. However, two versions are highly prevalent.
Because of the number of diseases and disorders linked to, the C677T mutation is the most frequent, most investigated, and regarded as very biologically essential.
Furthermore, both of these polymorphisms examines with multifactorial illnesses, with and without high homocysteine levels:
- Pregnancy problems or recurrent pregnancy loss
- Cardiovascular disease
- Defects in the neural tube
- Cancer danger
- Psychiatric illness
- Disorders of the nervous system
MTHFR has an impact on who it affects.
Interestingly, whereas MTHFR gene variants, they evenly distribute over the world. MTHFR deficiency is significantly more common in some parts of the world than in others.
At least one copy of a less-effective MTHFR gene variation is carried by roughly half of the population. Despite the fact that the gene has over 40 different variants, the C677T mutation is expected to be carried by 24% of the world’s population. C677T is least frequent in Africans (with a frequency of 10.3% ) and more common in North Americans and Europeans (31.2 percent and 34 percent, respectively), with South America, Asia, and Australia sitting somewhere in the middle.
A study that found that the amount of UV light in a location was a better predictor of C677T than latitude  provided an example of this. We also know that environmental pollutants can affect methylation and MTHFR expression epigenetically.
It is crucial to remember that, depending on where and how you live, these factors may significantly impact the health consequences of MTHFR polymorphisms.
- Yadav, Upendra, et al. “Distribution of MTHFR C677T gene polymorphism in healthy North Indian population and an updated meta-analysis.” Indian Journal of Clinical Biochemistry 32.4 (2017): 399-410.
- NIH. MTHFR gene variant. Genetic and Rare Diseases Information Center. Accessed May 6, 2019. https://rarediseases.info.nih.gov/diseases/10953/mthfr-gene-mutation
- Levin, Brooke Levenseller, and Elizabeth Varga. “MTHFR: addressing genetic counseling dilemmas using evidence-based literature.” Journal of genetic counseling 25.5 (2016): 901-911.
- Kaiser Permanente. “Basic Information About the MTHFR Gene.” The Permanente Medical Group, Inc. Copyright 2015, last reviewed 2018. https://mydoctor.kaiserpermanente.org/ncal/Images/GEN_MTHFR_tcm63-938252.pdf
- Contreras-Cubas, Cecilia, et al. “Heterogenous distribution of MTHFR gene variants among Mestizos and diverse Amerindian groups from Mexico.” PloS one 11.9 (2016): e0163248.
- Yafei, Wang, et al. “Is the prevalence of MTHFR C677T polymorphism associated with ultraviolet radiation in Eurasia?.” Journal of human genetics 57.12 (2012): 780.