What percentage of the population has the Methylenetetrahydrofolate Reductase (MTHFR) gene mutation?

From the Guidelines

Approximately 40.4% to 49.1% of the population carries the MTHFR 677 CT variant, and 13.0% to 23.6% carry the TT variant, according to the most recent study 1. Everyone has the MTHFR gene, as it's a normal part of human DNA. However, the frequency of genetic variants in homocysteine metabolism, such as the MTHFR 677 and 1298 variants, can vary significantly across different populations. The MTHFR gene is responsible for converting folate into its active form, methylfolate, which is important for numerous bodily functions including DNA synthesis and repair, neurotransmitter production, and homocysteine metabolism. Some key points to consider include:

• The MTHFR 677 CT variant is present in approximately 40.4% to 49.1% of the population, while the TT variant is present in 13.0% to 23.6% of the population 1.
• The MTHFR 1298 variant is also common, with the CT variant present in approximately 26.9% to 43.8% of the population, and the TT variant present in 3.4% to 7.5% of the population 1.
• Having an MTHFR mutation doesn't necessarily cause health problems for everyone, but some individuals may benefit from increasing folate intake through diet or supplements, particularly methylfolate (the active form) rather than folic acid.
• Genetic testing is available for MTHFR mutations, but it's essential to discuss the results with a healthcare provider who can provide personalized recommendations based on overall health status. It's also important to note that the relationship between MTHFR mutations and health outcomes is complex and influenced by multiple factors, including diet, lifestyle, and other genetic variants. Therefore, a comprehensive approach to healthcare is necessary to address the potential risks associated with MTHFR mutations, as suggested by recent studies 1.

From the Research

MTHFR Gene Variants and Population Frequency

• The frequency of MTHFR gene variants, such as C677T and A1298C, can vary among different populations 2.
• A study on Mexican Amerindians and Mestizos found that the 677T allele was most frequent in Mexican individuals, particularly in Amerindians, with a frequency of around 40-50% in some subgroups 2.
• In contrast, the frequency of the 1298C risk allele in Mexicans was found to be one of the lowest in the world, with a frequency of around 10-20% in some subgroups 2.
• Another study on a South Indian population found that the CT genotype of the MTHFR C677T polymorphism was associated with a risk for Down syndrome, with a frequency of 8.3% in case mothers and fathers 3.

Global Distribution of MTHFR Gene Variants

• The distribution of MTHFR gene variants can vary globally, with different populations exhibiting different frequencies of the C677T and A1298C alleles 2.
• A study on Mexican populations found that the frequency of the 677T allele was enriched in the South region of the country, followed by the Central East and South East regions 2.
• In contrast, the frequency of the 1298C allele was found to be lower in Mexican populations, with a frequency of around 10-20% in some subgroups 2.

Association with Diseases

• MTHFR gene variants have been associated with various diseases, including neural tube defects, cardiovascular diseases, and Down syndrome 2, 3.
• A study on children with multiple sclerosis found that increased homocysteine levels were associated with impaired folate metabolism and vitamin B deficiency, and that MTHFR gene variants may play a role in the development of the disease 4.
• Another study on renal transplant recipients found that hyperhomocysteinemia was associated with chronic allograft dysfunction, and that MTHFR gene variants may contribute to the development of this condition 5.