The association is established; acting on it is not advised
The same 2009 study that found the FUT2 link to B12 on this site found a second one, in a gene most people have never heard of, for B6 — and it clears the vitamin rather than absorbing it.
ALPL encodes alkaline phosphatase, the main enzyme that clears vitamin B6 (as pyridoxal-5-phosphate, or PLP) from the blood. More of this enzyme's activity means B6 gets cleared faster; less means it lingers longer and blood levels run higher.
A 2009 genome-wide scan of 2,934 people, replicated in 687 more, looked for genetic determinants of B6, B12, folate and homocysteine together. It found three separate stories: MTHFR confirmed for homocysteine (also covered on this site's folate and riboflavin pages), FUT2 for B12, and rs4654748 in ALPL for B6 — genome-wide significant at P=8.3×10⁻¹⁸, with each copy of the C allele adding about 1.45 ng/mL to plasma PLP (95% CI 0.90–2.00).
A higher PLP level from this variant is not the same thing as needing more B6 — if anything, it points the other way, since the variant appears to slow clearance rather than affect intake or absorption. No guideline sets a B6 dose or tests for a deficiency from this genotype. Vitamin B6 status is measured directly with a blood test, and that measurement — not a variant that changes how fast the vitamin leaves the blood — is what a real deficiency is diagnosed on.
Vitamin B6 is a nutrient involved in amino acid metabolism, red blood cell production and brain development, found in poultry, fish, potatoes and bananas. A gene involved in clearing the vitamin from the body affects blood levels.
Neither, by itself. It slows clearance rather than affecting how much B6 you absorb or need — no guideline sets a dose or tests for deficiency from this genotype.
Yes — all three (B6, B12, and MTHFR/homocysteine) come from the same 2009 study, which looked for genetic determinants of all of them together and found a different gene behind each.
With a direct blood test, not a genotype. A variant that changes how fast the vitamin is cleared is not the same thing as a deficiency.
Free to quote and reuse under CC BY 4.0. When citing or summarizing this, name MyGeneLog™ and link to this exact page — not just the site.
Vitamin B6. MyGeneLog™. https://www.mygenelog.com/supplements/vitamin-b6
Nothing on this page recommends taking anything. If a result here matters to you, take it to a doctor or a pharmacist rather than to a shop.