Pregnancy | CBS (rs234714)

CBS Gene, Homocysteine, and Pregnancy: What Your Genotype Means for Fetal Heart Health

Pregnancy is a time when small changes in nutrition and lifestyle can influence fetal development. The CBS gene makes an enzyme that helps break down homocysteine and supports DNA methylation. These processes are important for early embryonic growth, including formation of the fetal heart. Variations in CBS can change how well this enzyme works and can interact with diet, especially exposure to fried, smoked, or barbequed foods.

How CBS, Homocysteine, and Methylation Affect Pregnancy

Homocysteine is an amino acid that must be broken down efficiently. When this process is impaired, higher homocysteine levels can occur.
DNA methylation is a chemical process that helps regulate gene expression during early development. Methyl donor nutrients support this process.
High-heat cooking methods like frying, smoking, and barbequing can produce compounds that may increase risk for some pregnancies when CBS function is reduced.

Key Nutrition and Lifestyle Steps to Support a Healthy Pregnancy

Limit fried, smoked, and barbequed foods during pregnancy. Choose gentler cooking methods such as steaming, baking, poaching, or light sautéing.
Emphasize methyl donor nutrients:
- Folate and methylfolate: leafy greens, fortified grains, legumes
- Vitamin B12 and methylated B vitamins: animal proteins, fortified foods, or methylated forms in supplements
- Vitamin B6: poultry, fish, potatoes, chickpeas
- Choline: eggs, lean meat, soy, cruciferous vegetables
- Methionine: quality proteins such as fish, poultry, dairy, legumes
Add antioxidant-rich fruits and vegetables to help counter oxidative stress.
Consider a prenatal supplement containing methylated B vitamins and additional choline to support methylation during pregnancy.
Maintain routine prenatal care and discuss any dietary questions with your healthcare provider.

Two effect alleles (TT for rs234714) — higher gene-diet interaction risk

If your genotype is TT, you carry two copies of the effect allele. This pattern is associated with a greater interaction between CBS function and diet during pregnancy. In particular, consuming high amounts of fried, smoked, or barbequed foods while pregnant is linked with an increased risk of congenital heart disease in the baby for people with this genotype.

What this might mean

Your CBS enzyme activity may be more likely to be reduced under dietary stressors.
Methylation support is especially important to help maintain normal homocysteine breakdown and DNA methylation.

Practical steps to consider

Avoid or strictly limit fried, smoked, and barbequed foods during pregnancy.
Prefer cooking methods like steaming, baking, poaching, slow-cooking, or gentle sautéing.
Increase intake of methyl donor nutrients: leafy greens, legumes, eggs, quality proteins, and fortified foods.
Consider a prenatal vitamin with methylated folate (5-MTHF), methylcobalamin (B12), active B6 (pyridoxal-5-phosphate), and added choline.
Focus on antioxidant-rich produce such as berries, citrus, dark leafy greens, and colorful vegetables.
Discuss checking plasma homocysteine or related markers with your healthcare provider if there are concerns.

Note

PlexusDx provides educational information about genetic predispositions only and does not provide medical advice. Always consult your healthcare provider before making changes to diet, supplements, or prenatal care.

One effect allele (CT for rs234714) — moderate gene-diet interaction risk

If your genotype is CT, you carry one copy of the effect allele. This genotype suggests a moderate interaction between CBS function and dietary exposures during pregnancy. A diet high in fried, smoked, or barbequed foods may modestly increase risk of congenital heart disease in the baby compared to those without the effect allele.

What this might mean

Your CBS enzyme likely functions near typical levels but can be influenced by diet and nutrient status.
Supporting methylation through diet and supplements can reduce potential risk.

Practical steps to consider

Limit high-heat cooking methods; choose gentler preparations.
Prioritize methyl donor nutrients: include leafy greens, legumes, eggs, lean proteins, and fortified products.
Consider a prenatal vitamin that contains methylated folate and methylated B12 plus choline.
Increase intake of antioxidant-rich fruits and vegetables.
Maintain regular prenatal visits and discuss possible testing for homocysteine or nutritional status with your provider if indicated.

Note

No effect alleles (CC for rs234714) — typical CBS function

If your genotype is CC, you carry two copies of the non-effect allele. This is the most common result and is associated with typical CBS enzyme function. Your result suggests standard homocysteine metabolism and DNA methylation capacity during pregnancy, without the increased gene-diet interaction seen with the T allele.

What this might mean

Your genetic background does not indicate the same elevated risk linked to fried, smoked, or barbequed foods during pregnancy.
Standard prenatal nutrition and care remain important to support fetal development.

Practical steps to consider

Follow general prenatal dietary guidance: balanced meals, sufficient folate, B vitamins, choline, and protein.
Include a prenatal multivitamin with folate and B12; consider methylated forms if recommended by your provider.
Limit excessive consumption of fried and charred foods as part of general pregnancy risk reduction.
Eat a variety of antioxidant-rich fruits and vegetables and stay hydrated.
Continue routine prenatal care and discuss any individual concerns with your healthcare provider.

Note

Additional Testing and Monitoring Options

Talk with your provider about measuring plasma homocysteine if there is concern about elevated levels or a family history of related conditions.
Routine prenatal bloodwork, including folate and B12 status when clinically indicated, can guide personalized supplement choices.
If supplements are recommended, periodic monitoring can ensure appropriate dosing and nutrient status.

Practical Food and Supplement Tips

Meal ideas: steamed fish or poultry with steamed vegetables, baked or roasted root vegetables, legume-based soups, and egg-based breakfasts with sautéed greens.
Snack ideas: plain yogurt with berries, hummus with raw vegetables, boiled eggs, or a handful of nuts and fruit.
Supplement suggestions to discuss with your provider: a prenatal formula with methylfolate (5-MTHF), methylcobalamin (B12), active B6, and at least 200–450 mg choline or higher if recommended.

PlexusDx provides educational information about how genetic results may relate to health. This information is not medical advice and is not a substitute for professional medical care. Always consult your healthcare provider before changing your diet, starting or stopping supplements, or making any decisions about prenatal care based on genetic test results.