BCMO1 rs12934922: What Your Genotype Means
The rs12934922 variant is a single nucleotide polymorphism located in the BCMO1 gene. It is associated with reduced catalytic efficiency of the BCMO1 enzyme, which plays a critical role in converting dietary beta-carotene into vitamin A.
What each genotype means
Typical conversion efficiency
This genotype represents the most common form of the BCMO1 enzyme, which is typically efficient at converting dietary beta-carotene into active vitamin A. Individuals with this profile generally do not have the specific genetic reduction in catalytic activity associated with this variant. Please consult with a healthcare provider or registered dietitian to ensure your dietary intake of vitamin A meets your individual needs.
This is the most common genotype in most global populations, though frequencies vary by ancestry.
Likely reduced conversion efficiency
Carrying one copy of the T allele is associated with a reduction in the catalytic efficiency of the BCMO1 enzyme compared to those with the AA genotype. This may result in a decreased ability to convert plant-based beta-carotene into active vitamin A. You should discuss your vitamin A status and dietary sources with a clinician or pharmacist to determine if adjustments to your intake are appropriate.
This genotype is common, appearing in a significant portion of Western populations where the T allele frequency is approximately 0.25 to 0.30.
Reduced conversion efficiency
Carrying two copies of the T allele is associated with a more pronounced reduction in the catalytic efficiency of the BCMO1 enzyme. Research suggests this may limit the body's ability to effectively transform dietary beta-carotene from plant sources into usable vitamin A. It is recommended that you discuss your vitamin A levels and potential reliance on direct vitamin A sources with a healthcare professional or pharmacist.
This genotype is less common than the heterozygous state, occurring in a smaller percentage of the population depending on ancestral background.
Understanding the rs12934922 Variant
The rs12934922 variant is a specific genetic change, or single nucleotide polymorphism (SNP), located within the BCMO1 gene on chromosome 16. In genetic terms, this variant is often referred to as R267S, indicating a change in the amino acid sequence of the resulting protein. This SNP is categorized as a missense variant, meaning the change in the DNA code results in the substitution of one amino acid for another in the BCMO1 enzyme. Researchers study this variant because it sits in a region of the gene that is essential for the enzyme's normal function. By analyzing this specific location, scientists aim to understand why some individuals process dietary nutrients differently than others. While this variant is well-documented in genetic databases, it is important to note that it is just one of many factors that influence how your body processes vitamins and nutrients from your diet.
The Role of the BCMO1 Gene
The BCMO1 gene provides instructions for making an enzyme called beta-carotene oxygenase 1. This enzyme is primarily responsible for the oxidative cleavage of beta-carotene, a pigment found in many orange and yellow vegetables, into two molecules of retinal, which is a form of vitamin A. This process is a vital step in human metabolism, as it allows the body to utilize plant-based provitamin A carotenoids to meet its vitamin A requirements. Vitamin A is essential for maintaining healthy vision, immune function, and skin health. When the BCMO1 enzyme functions optimally, the body efficiently converts dietary beta-carotene into active vitamin A. However, variations in the BCMO1 gene can alter the structure of this enzyme, potentially leading to differences in how effectively an individual can produce vitamin A from their diet. Understanding this gene helps researchers explore the biological basis for the wide variability observed in how people respond to dietary carotenoids.
Research and Evidence Strength
Research into rs12934922 has primarily focused on its impact on the catalytic activity of the BCMO1 enzyme. Studies, including in vitro biochemical characterizations, have demonstrated that the presence of the variant allele can lead to a reduction in the enzyme's ability to convert beta-carotene into retinal. Some research suggests that when this variant is combined with other common SNPs in the same gene, such as rs7501331, the reduction in catalytic efficiency can be even more pronounced. While these findings are significant in a laboratory setting, the evidence regarding the clinical impact of this variant on overall health outcomes remains limited. The conversion of beta-carotene is a complex process influenced by many factors, including overall diet, gut health, and other genetic modifiers. Consequently, while the association between this variant and reduced enzyme efficiency is supported by scientific literature, it is not currently used as a diagnostic tool for clinical vitamin A deficiency.
Practical Considerations for Consumers
If you have received information about your BCMO1 genotype, it is important to view it as one piece of a much larger nutritional puzzle. The presence of the variant allele does not mean you are incapable of obtaining sufficient vitamin A; rather, it may suggest that your body's efficiency in converting plant-based beta-carotene is lower than average. This information can be used to personalize your nutritional approach, such as ensuring a diverse intake of both plant-based and pre-formed vitamin A sources. However, this genetic information should never be used to diagnose a medical condition or to replace professional medical advice. If you are concerned about your vitamin A levels or are considering significant changes to your diet or supplementation, you should discuss these findings with a registered dietitian, your primary care physician, or a pharmacist. They can help you interpret these results in the context of your overall health, blood work, and specific nutritional needs.
How common is this variant?
The minor allele frequency (T) for rs12934922 is approximately 0.25 to 0.30 in many Western populations, though frequencies can vary significantly across different global ancestries.
Frequently asked questions
Does having the rs12934922 variant mean I have a vitamin A deficiency?
No, having this variant does not mean you have a vitamin A deficiency. It simply suggests that your body may be less efficient at converting beta-carotene from plants into active vitamin A, which is one of several ways the body obtains this nutrient.
Should I take vitamin A supplements if I have the T allele?
You should not start or change any supplementation based solely on genetic results. Please consult with your healthcare provider or a registered dietitian to assess your actual vitamin A status through blood tests before considering supplementation.
Can I overcome the effects of this variant with my diet?
Many people with this variant maintain healthy vitamin A levels by consuming a balanced diet that includes both plant-based carotenoids and pre-formed vitamin A found in animal products. A professional nutritionist can help you design a diet that meets your specific needs.
Is this genetic test used to diagnose health conditions?
No, this variant is not used for clinical diagnosis. The evidence linking this SNP to specific health outcomes is limited, and it is generally considered a tool for understanding individual nutritional variability rather than a medical diagnostic test.
Sources & further reading
Educational information only, last refreshed 10/10/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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Coding variant that exhibits an additive effect with rs12934922 in reducing enzymatic cleavage of dietary provitamin A carotenoids.
Influences the enzymatic conversion efficiency of dietary beta-carotene into active vitamin A (retinol).
This coding variant reduces beta-carotene 15,15'-monooxygenase activity, impairing the enzymatic conversion of provitamin A carotenoids into active retinal.