DAO Catalyzes the degradation of compounds such as putrescine, histamine, spermine, and spermidine, substances involved in allergic and immune responses, cell proliferation, tissue differentiation, tumor formation, and possibly apoptosis. Placental DAO is thought to play a role in the regulation of the female reproductive function. www.uniprot.org

DAO is calcium, copper, zinc and quinone binding. Some of DAO’s biological processes are the glyoxylate metabolic process, dopamine biosynthetic process and the proline catabolic process.

When DAO deficient, we can end up with with hyperoxaluria.  Oxalates can shut down methionine synthase and that is where genes like MTR, MTRR and MTHFR can be impacted.



GAD catalyzes the production of GABA and when the GAD gene is not working there is usually a problem with excessive amounts of glutamate.
One of the reasons that we can have problems with GAD is that we are P5P deficient.

When P5P deficient, there are excessive oxalates which then can shut down methionine synthase.  MTHFR is part of methionine synthase.



CBS is  hydro-lyase catalyzing the first step of the transsulfuration pathway, where the hydroxyl group of L-serine is displaced by L-homocysteine in a beta-replacement reaction to form L-cystathionine, the precursor of L-cysteine. This catabolic route allows the elimination of L-methionine and the toxic metabolite L-homocysteine.

P5P is the cofactor for CBS. So again if P5P is deficient in the body then sulfation will not work and methionine synthase will become compromised and MTHFR is a part of methionine synthase.



The COMT gene is responsible for breaking down estrogen and the catecholamines dopamine, epinephrine and norepinephrine. When COMT is downregulating and someone is having a hard time breaking down catecholamines, methylfolate at high doses can induce panic, anxiety and make matters worse. So it is important to know that if 5 MTHF is needed for MTHFR, it  is to be used with caution on individuals with this issue. As we know folate is needed during pregnancy so it is a must. Remember when folate levels get excessive in these individuals that working with a practitioner is important.



When G6PD deficient the body will have a hard time making NADPH. The catalytic activity for MTHFR is 5 MTHF and NADP which then converts to 5, 10 MTHF and NADPH.


If you are interested in learning more about your DNA, you can order a 23andme kit or an ancestry kit from www.23andme.com or www.ancestry.com and then use our “Sterling’s App” at mthfrsupport.com.
We also have the SNPbit compendium that provides you with a guide to the SNPs on the V2.2 variant report.