"VDR Taq: Vitamin D Receptor Taq Abnormality -Vitamin D has many functions, an issue because 90% of my patients have low or low normal Vitamin D levels. Pertinent to this discussion, Vitamin D stimulate the enzymes that generate dopamine, a good reason to keep your Vitamin D level up, as we need dopamine to defend against microbes and metals, and to keep our mood up. While we utilize SAMe (and indirectly other methyl group donors) to degrade dopamine, we also utilize methyl donors to generate dopamine. Individuals with a normal Vitamin D receptor, those who are VDR Taq (-/-), make plenty of dopamine. They tend not to need or to tolerate methyl groups or dopamine precursor substances. With respect to methyl group need and tolerance, they behave like COMT (+) individuals. Individuals (+/+) or (+/-) for VDR Taq defect have lower Vitamin D levels, make less dopamine, and will need and tolerate dopamine precursor substances and methyl donors. With respect to methyl donor tolerance, VDR Taq (+) individuals behave like COMT (-) individuals. All sorts of permutations are possible here, impacting on your tolerance and need for dopamine precursors and methyl groups. I acknowledge that this is all very difficult to understand. Hopefully the chart below will help."
COMT (+/+) + VDR Taq (-/-)
Highest dopamine levels
Better tolerance to toxins and microbes
Low need tolerance for dopamine precursors and methyl donors
Greatest susceptibility to mood swings
In such as individual, we would utilize the “un methylated” forms of Methyl Cycle intermediates. If an MTR/MTRR defect increases your need for methyl-B12, in this individual we would start with hydroxy-B12, to avoid ODing you with methyl groups, expecting that with enough hydroxy-B12 and free methyl groups floating around you will form up some methyl-B12, even if MTRR activity is compromised by a defect. We would not give your dopamine precursors such as quercetin or the herb macuna puriens. We would not advise a diet high in tyrosine, the amino acid precursor of dopamine. COMT (+/+) VDR Taq (-/-) individuals will be susceptible to iodine and lithium depletion as they detoxify, and we will have to watch for this and supplement accordingly.
COMT (-/-) + VDR Taq (+/+)
Lowest dopamine levels
Poor tolerance to toxins and microbes
Needs and tolerates dopamine precursors and methyl donors
Lowest susceptibility to mood swings
In such an individual, we would utilize the methylated forms of Methyl Cycle intermediates, including methyl-B12 if n TR/MTRR defect is present. Dopamine precursors such as quercetin, ginkgo biloba, and the herb macuna puriens might be helpful, as would a diet high in tyrosine, the amino acid precursor to dopamine. Other methyl donors, including melatonin, TMG, turmeric, theanine, along with MSM and SAMe (the latter two only for CBS (-/-) individuals) would make sense. To support BHMT, instead of Phosphatidylserine, we would use Pedi-Activ, which contains Phosphatidylserine and DMAE, a methyl donor. Rather than using GABA to deal with excitotoxicity, we would use Zen, which combines GABA with the methyl donor threanine.
COMT (+/-) and VDR (-/-) behaves like COMT (+/+)
COMT (+/-) and VDR (+/+) behaves like COMT (-/-)
Multiple (+/-) combinations of COMT and VDR Taq are possible. We will address these “intermediate” genotypes with intermediate levels of methyl group supplementation.
COMT H62H (+/+) Highest dopamine levels COMT L136L (+/+) Lowest need for and tolerance to methyl group donors COMT 61 (-/-) Greatest susceptibility to mood swings |
COMT H62H (-/-) Lowest dopamine levels COMT L136L (-/-) Greatest need for and tolerance to methyl group donors COMT 61 (+/+) Lower susceptibility to mood swings* |
Both the COMT and VDR Taq status determine
need and ability to tolerate methyl donors. This chart goes from highest need for methyl donors to lowest need and ability to tolerate methyl donors.
COMT V158M/H62H-- VDR Taq++/TT need the most methyl donors
COMT V158M/H62H -- VDR Taq +-/Tt
COMT V158M/H62H -- VDR Taq --/tt
COMT V158M/H62H +-VDR Taq++/TT
COMT V158M/H62H +-VDR Taq +-/Tt
COMT V158M/H62H +-VDR Taq --/tt
COMT V158M/H62H ++VDR Taq++/TT
COMT V158M/H62H ++VDR Taq +-/Tt
COMT 61, V158M/H62H ++VDR Taq--/tt exquisitely sensitive to methyl donors