MTHFR (methylenetetrahydrofolate reductase) is a gene. The gene encodes the MTHFR enzyme which is in charge of a multi-step process converting homocysteine into another amino acid – methionine.
Our bodies use methionine to produce proteins and other vital compounds; methionine is also an important antioxidant in the body for the production of healthy eggs and sperm. An irregular change in gene structure, called a mutation, of the MTHFR gene can cause:-
- an interruption of the MTHFR enzyme’s regular function of breaking down homocysteine
- an inability to appropriately process B vitamins. People with MTHFR gene mutations can have high levels of homocysteine but not everyone with the MTHFR gene mutation has a homocysteine issues.
MTHFR Gene mutation
Over the years many MTHFR gene variants have been identified and common mutations include C677T and A1298C, with the first being more serious out of the two. While you most likely only heard about MTHFR when it affected you, or someone close to you, it’s not uncommon nor is it rare.
The MTHFR C677T mutation is found in over five to 10 per cent of the population and the A1298C MTHFR mutation affects some 20 to 30 per cent of people. Some people have a genetic mutation in one or both of their MTHFR genes.
- People with mutations in one MTHFR gene are called heterozygous for the MTHFR mutation
- People with mutations found in both genes, are called homozygous for the MTHFR mutation
Genetic variation in this gene influences peoples susceptibility to:-
- methylenetetrahydrofolate reductase deficiency
- cardiovascular disease, neural tube defects
- recurrent pregnancy loss and infertility
- colon cancer and acute leukaemia
MTHFR and Pregnancy
One of the main issues with the prevalence of the MTHFR gene is a homocysteine build up which can cause problems with blood clots and had been widely linked to recurrent miscarriages.
While some MTHFR mutations are not a cause for concern, others are. If a woman has had several miscarriages or a couple has suffered long standing infertility, they should be tested for the MTHFR gene mutation.
According to MTHFR expert Dr Ben Lynch, of www.mthfr.net, MTHFR and recurrent pregnancy loss are linked particularly if you have:
- 1 or more copies of the C677T MTHFR mutation or
- 1 copy of each (1298 and 677) or
- 2 copies of A1298C or
- A single copy of A1298C MTHFR mutation may not be related – however, I am still on the fence about this for various reasons
MTHFR and Miscarriage
If you and your partner are experiencing recurrent miscarriages it’s important to look further than just the woman’s physiology and both partner’s genetics, among other things, need to be examined.
A Turkish study found that recurrent miscarriage causes
“is related to combined parental (not only maternal) thrombophilic gene mutations…heterozygosity of FVL, FVR2, ACE, and ApoE2 genes in both parents play crucial role in RPL (recurrent pregnancy loss) and should be considered as a risk factor in RPL.”
This means that the father’s genetics have a direct connection in the blood clotting risk in the developing child.
Similarly a Chinese study published in BMC Medicine states that
“defects in DNA maintenance methylation in the embryo, not in the mother, are associated with abnormal embryonic implantation and development. The findings of the current study provide new insights into the etiology of early pregnancy loss (EPL)… We also found that disturbance of maintenance methylation with a DNMT1 inhibitor may result in a decreased global DNA methylation level and impaired embryonic development in the mouse model, and inhibit in vitro embryo attachment to endometrial cells.”
The methylation in the developing child is directly correlated to a healthy pregnancy outcome – regardless of the methylation status of the mother or father.
Health promotion and prevention is the best medicine. A pre-conceptual assessment and customised supplementation regime for both prospective parents is important to maximising your fertility and chances of conceiving and delivering a healthy baby. Manage the fertility issues of MTHFR by booking a consultation with one of our expert fertility team, we can help.
Ozdemir, O 2012, ‘Recurrent pregnancy loss and its relation to combined parental thrombophilic gene mutations’, Genetic Testing and Molecular Biomarkers, vol. 4, p. 279-86.
Yin, Li-Jun 2012, ‘Insufficient maintenance DNA methylation is associated with abnormal embryonic development’, BMC Medicine, p. 10-26.