Vitamin B12 is a water-soluble vitamin that is essential for proper red blood cell formation, neurological functioning, and DNA synthesis. The prevalence of vitamin B12 deficiency is at least 47% in the Indian population. According to a few studies, mutations in the genetic variants responsible for poor absorption of vitamin B12 can put you at a big risk for its deficiency. Commonly observed symptoms of vitamin B12 deficiency include fatigue, vision loss, and depression.
Vitamin B12 test
A study conducted to identify the prevalence of Vitamin B12 deficiency in India showed that nearly 33% of the 2403 adolescents tested in Haryana were deficient. The high prevalence of deficiency is indicative of the poor nutritional status, warranting greater awareness about vitamin B12 test and cost. An understanding about the micronutrient status of an individual, will help in catering to the unique nutritional needs.
How do genetic variants affect vitamin B12 status?
Genetic variants are associated with the proteins involved in vitamin B12 absorption, cellular uptake and intracellular metabolism, thereby, affecting the level of vitamin B12. Twin studies have shown that the heritability of vitamin B12 levels was 59%, highlighting the significance of genetic variants on vitamin B12 status.
To understand the influence of genetic variants on vitamin B12 levels in the body, it is important to understand the various proteins associated with vitamin B12 absorption and metabolism.
Vitamin B12 absorption and cellular uptake: In order to maintain optimum levels of vitamin B12 in the body, there should be sufficient intake of vitamin B12 rich foods and the body should then be able to absorb the vitamin B12 from such food sources. There are three important binding proteins that play a role in vitamin B12 absorption.
- Haptocorrin (HC)– also called transcobalamin I or R binder
- Intrinsic factor (IF)
- Transcobalamin II (TC)
Genes involved in Vitamin B12 status:
- TCN1: The TCN1 gene codes for the production of transcobalamin I protein that binds to vitamin B12. Six research studies have shown that genetic variants in this gene are associated with circulating levels of vitamin B12.
- FUT2: The fucosyltransferase 2 (FUT2 gene) is also known as the Secretor gene as it codes for a secretor enzyme α (1,2) fucosyltransferase that is known to fucosylate oligosaccharides. Genetic variants in this gene have been associated with the composition of the gut microbiome. People who carry the non-secretor variant of this gene, have lower microbial composition and diversity as the microbes will not be able to utilize host-derived glycans.
Helicobacter Infection and FUT2 gene variants: Genetic variants in the FUT2 gene is also known to potentially alter the susceptibility to Helicobacter pylori (H. pylori) infection, along with the associated gastric-induced vitamin B12 malabsorption. H.pylori, which is a gastric pathogen, binds to α1,2-fucosylated glycans on epithelial cells. H. pylori infections are known to interfere with the release of intrinsic factor, a binding protein required for vitamin B12 absorption.
- CUBN: The intestinal intrinsic factor receptor or intrinsic factor-cobalamin (IF-B12) receptor is also known as cubulin (CUBN). This receptor is expressed on the epithelial cells of the kidney and the intestines, and is associated with the vitamin B12- intrinsic factor uptake into the cells. Genetic variants in the CUBN gene are associated with vitamin B12 status.
Who should take up a vitamin B12 test?- Symptoms of vitamin B12 deficiency
A genetic vitamin B12 test will help in identifying vitamin B12 needs of the body. The symptoms of vitamin B12 deficiency are as follows:
- Sore mouth or tongue
- Rapid heart beat
Conditions like pernicious anemia and high homocysteine levels can also be influenced by the level of vitamin B12.
What is the difference between genetic vitamin B12 test and routine blood testing for the level of vitamin B12?
Blood testing for vitamin B12 provides the vitamin B12 levels at that point in time. This may be influenced by the consumption of a diet particularly rich in vitamin B12, which may not be the case normally. Genetic testing is static, it does not change over time as the genome data remains the same. Both the tests are complementary and the results should be taken together for health information discovery.
Genetic testing provides long term information, helping an individual structure dietary intake to suit the specific needs of the body.
How to interpret a genetic vitamin B12 test report?
The genetic variants associated with vitamin B12 levels are used to indicate vitamin B12 needs. An individual who has ‘significantly increased needs’ for vitamin B12 will have lower absorption or uptake of vitamin B12. If the blood levels of vitamin B12 also indicate low vitamin B12 levels then there should be a significant increase in vitamin B12 intake. However, for such an individual, if the blood levels indicate normal levels of vitamin B12, then the diet consumed is already compensating for increase vitamin B12 needs.
What are the foods rich in Vitamin B12?
Vitamin B12 is found in animal sources like meat, eggs, fish, poultry, milk and milk products. There are no known plant sources of vitamin B12, therefore, vegetarians are at an increased risk. Currently, there are fortified cereals which provides vegetarians with a source of vitamin B12.
What is the range of Vitamin B12 levels in the blood?
|Level of Vitamin B12 in the blood (ng/L)||Effect|
|100-200||Borderline vitamin B12 deficiency|
|<100||Vitamin B12 deficiency|
How much does a vitamin B12 test cost?
The vitamin B12 test cost includes information on the needs of numerous vitamin and minerals as well as the response of the individual to macronutrient intake, as it is a part of the nutrition module. It is not a stand alone product.
Vitamin B12 test cost- 9900 ( inclusive of DNA analysis)
Vitamin B12 test cost- 2500 ( if DNA raw data is provided)
To find out more about the vitamin B12 needs of your body, order your genetic nutrition report here.