Margie GanderApr 24, '20

Depression, mood problems, and anxiety are not things that people like to talk about. Sometimes they are perceived as a "weakness". It's definitely difficult to tell people that you are taking an anti-depressant. And it is even more challenging to come off your medication too. Ask me, I know. 

I've struggled with mood and anxiety my whole life. It runs in my family but I never realised - until I did DNA testing - how much of a role my genes played. Knowing that I've got a genetic predisposition for anxiety, heightened stress response, and poor serotonin production has been a game-changer. Firstly, there is no shame, just a greater appreciation for how unique I am and how my biochemistry needs very specific support.

My journey to this point has not been easy as I was on Aropax for nearly 10 years after I was diagnosed with ovarian cancer at 36 and went into menopause at 37.  This then was compounded with the loss of my beloved Dad a year later. Carolyn Myss, Ph. D. in Energy Medicine calls these periods in our lives "the dark night of the soul" and that's exactly how it felt. 

This year I decided to come off my medication. It was awful. But while I suffered 4 weeks of dizziness, insomnia, and weird sensations in my hands and feet; I decided to go back to the very beginning and reassess my genes, my GUT, and neurotransmitters' function. 

I don't advocate that you stop any medication without the support and guidance of your doctor, but if you are like me and you want to get to the root cause of your health challenges, then starting here is a great place to begin. 

What are neurotransmitters?

Neurotransmitters are endogenous chemicals (meaning that they originate from inside your body) that enable neurotransmission. They are a type of "chemical messenger" which transmits signals across a chemical synapse from one neuron to another 'target' neuron.

These chemical messengers can affect a wide variety of both physical and psychological functions including heart rate, sleep, appetite, mood, and fear. Billions of neurotransmitter molecules work constantly to keep your brain functioning, managing everything from your breathing to your heartbeat to your learning and concentration levels.

In order for neurons to send messages throughout the body, they need to be able to communicate with one another to transmit signals. However, neurons are not simply connected to one another. At the end of each neuron is a tiny gap called a synapse and in order to communicate with the next cell, the signal needs to be able to cross this small space. This occurs through a process known as neurotransmission. Neurotransmitters act like a key, and the receptor sites act as a lock. It takes the right key to open specific locks. 

Many neurotransmitters are produced in your GUT as well as in your brain, including dopamine, GABA, serotonin, and endocannabinoids. In fact, roughly 95% of the serotonin in your body comes from your GUT so people are right when they talk about a "GUT-feeling"!

Studies have pointed to possible connections between dysfunction in neurotransmitters to several neurological and psychiatric disorders, including Parkinson's disease, Alzheimer's disease, depression, and fibromyalgia.

It is easy to see that if you are not making sufficient neurotransmitters, or are not transmitting them efficiently, or are not able to receive them correctly; how you can begin to feel out of sorts. So what causes this to happen?

The "neurotransmitter" genes

There are certain, well-researched genes that play a role in the production, transportation, reception, and removal of all the major neurotransmitters in your body. 

Carrying a genetic "misspelling" in one or more of these genes can predispose you to poor neurotransmitter regulation; so it is ideal to start with determining your "mood" genotype.

Gene  Risk genotype  Function  Neurotransmitter  Test



Encodes for oxytocin are a peptide hormone and neuropeptide that is involved in the regulation of mood, anxiety, and social biology. It plays a role in social bonding, sexual reproduction in both sexes, and during and after childbirth. 
Encodes the important enzyme, tryptophan hydroxylase 2 that makes serotonin. TPH2 is produced most significantly in the brain stem. The encoded protein catalyses the first and rate-limiting step in the biosynthesis of serotonin, an important hormone, and neurotransmitter.
Serotonin  GENEWELL 
HTR1A G-allele
Encodes a G protein-coupled receptor for serotonin (5-hydroxytryptamine) and belongs to the 5-hydroxytryptamine receptor subfamily. Serotonin has been implicated in a number of physiologic processes and pathologic conditions. Inactivation of this gene results in behavior consistent with an increased anxiety and stress response. 
MAO-A T and C allele 
The so-called "warrior gene" encodes the monoamine oxidase A (MAO-A) enzyme in the brain that breaks down neurotransmitters such as noradrenaline, adrenaline, serotonin, and dopamine. 





Provides instructions for making an enzyme called methylenetetrahydrofolate reductase. This enzyme plays a role in processing amino acids, the building blocks of proteins. 
Provides precursors B6, B12 & methionine 
Encodes the mu receptor by a substance such as morphine causes sedation, euphoria & decreased respiration.
SLC6A4  C-allele
Encodes an integral membrane protein that transports the neurotransmitter serotonin from synaptic spaces into presynaptic neurons.
Encodes Ankyrin-3, which plays a key role in sodium channel functioning and regulation of excitatory signalling. The gene has been linked to conditions characterised by mood instability.
ANKK1   A-allele Involved in dopamine reward and addiction response. Dopamine



Provides instructions for making a protein called apolipoprotein E.
Cholesterol is a ubiquitous partner of neurotransmitter receptors
BDNF T-allele
Provides the instructions for making a protein found in the brain and spinal cord called brain-derived neurotrophic factor.
BDNF protein is active at the connections between nerve cells (synapses)
encodes the COMT enzyme, which is an important catabolic enzyme, especially in the prefrontal cortex, where it degrades adrenaline, noradrenaline & estrogen




Acts as a co-chaperone that modulates not only glucocorticoid receptor activity in response to stressors but also a multitude of other cellular processes in both the brain and periphery. 
GABRA6  C Plays a role in GABA binding  GABA
5-HT2A AA 
Encodes for the serotonin receptor to be activated by contact with serotonin causing an excitatory effect and stimulating smooth muscle contraction in the GI tract (increasing gut motility)
Serotonin  VitaGEN + VitaTHYROID + VitaFEM
BHMT02  A 
The activity of this gene can be affected by stress, cortisol levels and may play a role in ADD/ADHD by affecting norepinephrine levels. BHMT-02 plays a role in the GUT-brain axis, playing a role in how an individual is able to concentrate while under the effects of stress.
DRD2 G -allele
The dopamine receptor DRD2 functions to regulate the synthesis, storage, and release of dopamine.
 Dopamine   GENECOMBO

The role of the GUT

The microbiota in your GUT has been found to communicate with the brain through several different mechanisms. This includes the production of neurotransmitters, their modulation as well as the breakdown of neurotransmitters. 

This interaction between the GUT and the brain is made even more complex considering that hormones, in particular steroid hormones, can influence your GUT microbiota and, in turn, your GUT bacteria can influence circulating hormone levels. Furthermore, stressors from the environment such as the endocrine disruptors may influence the GUT bacteria composition as well as inflammation of your GUT lining. 

You can see how important a healthy, well-balanced GUT is for maintaining good brain health! 

To determine the "landscape" of our GI tract, the GI MAP is a very useful tool:



I just love this table as it provides you with insight as to the relationship between key neurotransmitters and GUT bacteria.

Neurotransmitters Function Microbiota 
Dopamine is one of the major neurotransmitters in reward-motivated behavior, and is a precursor for other catecholamines, like norepinephrine and epinephrine
Members of the Bacillus and Serratia
Serotonin is involved in regulating numerous physiological processes, including gastrointestinal secretion and peristalsis, respiration, vasoconstriction, behavior, and neurological function

Lactococcus lactis

Lactobacillus plantarum

Streptococcus thermophiles


Morganella morganii

Klebsiella pneumoniae

Hafnia alvei



Gamma-aminobutyric acid (GABA)
GABA is the major inhibitory neurotransmitter of the central nervous system, and it and its receptors are widely distributed throughout the mammalian host. Substantial literature supports the link between altered GABAergic neurotransmission and numerous CNS disorders, including behavioral disorders, pain, and sleep

Lactococcus species

Aspergillus nidulans

The only neurotransmitter in its class. Found in both the central and peripheral nervous systems, it is the primary neurotransmitter associated with motor neurons.

 It plays a role in muscle movements as well as memory and learning.

Lactobacillus species
Acts as a neurotransmitter in the brain and spinal cord. It plays a role in allergic reactions and is produced as part of the immune system's response to pathogens.
Lactobacillus reuteri


The special role of amino acids

To function adequately, the central nervous system (CNS) requires a number of amino acids found in protein foods. Amino acids such as tryptophan, tyrosine, histidine, and arginine are used by the brain for the synthesis of various neurotransmitters and neuromodulators.

Having a low amino acid profile can lead to mood problems and compromised brain health. Measuring and tracking your amino acid levels is a great way to evaluate your diet to determine whether you are consuming enough of all the important amino acids.

The amino acid profile test is the perfect tool to determine this:




The "food-mood" connection is very important as food acts as a precursor to neurotransmitters' production and regulation. 

In general, there are many nutrients essential to the synthesis and regulation of neurotransmitters, including amino acids, choline, vitamin C, B-vitamins, zinc, iron, omega-3 fatty acids, and vitamin D.

If you are struggling with mood, or you just want to support your body better; then this table of foods and micronutrients in a bioavailable supplement form is really helpful. 

Neurotransmitter  Role Foods  Supplement


The only neurotransmitter in its class. Found in both the central and peripheral nervous systems, it is the primary neurotransmitter associated with motor neurons. It plays a role in muscle movements as well as memory and learning.
Aubergine, bitter orange, mung bean, pea, radish, spinach, squash, wild strawberry
Amino acids:
Glutamate  An excitatory neurotransmitter & the most plentiful neurotransmitter found in the nervous system where it plays a role in cognitive functions. Excessive amounts of glutamate can cause excitotoxicity resulting in cellular death. This excitotoxicity caused by glutamate build-up is associated with some diseases and brain injuries including Alzheimer's disease4, stroke, and epileptic seizures.
Caviar, cheese,  fish, meats, miso, mushrooms, seafood, seaweeds, soups, soy sauces, spinach, stews, tomato, tomato sauce

Gamma-Aminobutyric Acid

Acts as the body's main inhibitory chemical messenger. GABA contributes to the vision, motor control, and plays a role in the regulation of anxiety. 
Barley, broccoli, buckwheat, kale, oat, pea, potato, rice, shiitake, soya bean, spinach, St John’s wort, sweet potato, tea, tomato, valerian, wheat, wild celery
Involved in reward, motivation, and additions. Several types of addictive drugs increase dopamine levels in the brain. Parkinson's disease, which is a degenerative disease that results in tremors and motor movement impairments, is caused by the loss of dopamine-generating neurons in the brain.
Aubergine, avocado, banana, common bean, apple, orange, pea, plantain, spinach, tomato
Regulates & modulates mood, sleep, anxiety, sexuality, and appetite.
Bananas, chicory, coffee, hazelnut, kiwi, lettuce,  passion fruit, pawpaw, pepper, pineapple, plum, pomegranate, potato, spinach, strawberry, tomato,wild rice.
Acts as a neurotransmitter in the brain and spinal cord. It plays a role in allergic reactions and is produced as part of the immune system's response to pathogens. 
Anchovy, beer, Champagne  dandelion, fermented sausages, cured meat products, ketchup, aged cheeses, red, white and dessert wines, sardine, sauerkraut, soybean food products (for example, soy, tempeh, soy sauce, soya  pasteurized, and fresh milk, yoghurt
UltraFlora Balance 


(to support serotonin) 

It is essential in humans, meaning the body cannot synthesize it; it must be obtained from the diet. Tryptophan is also a precursor to the neurotransmitter serotonin, the hormone melatonin, and vitamin B3. 
Dark chocolate, oats, dried dates, milk, yogurt, cottage cheese, red meat, eggs, fish, poultry, sesame, chickpeas, almonds, sunflower seeds, pumpkin seeds, buckwheat, spirulina, and peanuts.
BioPure Protein
An organic chemical in the catecholamine family that functions in the brain and body as a hormone and neurotransmitter.
Foods high in C, B vitamins (especially B-5 and B-6), and magnesium to help support healthy adrenal glands.
Adrenal Support
Produced by both the adrenal glands and a small number of neurons in the medulla oblongata, where it acts as a neurotransmitter involved in regulating visceral functions
C, B vitamins (especially B-5 and B-6), and magnesium
Acts as a neuromodulator in the brain & is involved in suppressing arousing and improving sleep.
Grass-fed meat, pastured poultry, organ meats, wild-caught fish & seafood, such as salmon, sardines, halibut, orange roughy, tuna, ling, pike, cod, cusk, sunfish, haddock and whitefish, free-range eggs, nuts, seeds, whole grains, dark leafy green vegetables
Acts as a neurotransmitter in the central & peripheral nervous systems. It plays a role in autonomic control, sensory transduction, and communication with glial cells. Research suggests it may also have a part in some neurological problems including pain, trauma, and neurodegenerative disorders.
Grass-fed meat, pastured poultry, organ meats, wild-caught fish & seafood, such as salmon, sardines, halibut, orange roughy, tuna, ling, pike, cod, cusk, sunfish, haddock and whitefish, free-range eggs, nuts, seeds, whole grains, dark leafy green vegetables. And Exercise! 
Nitric oxide
Plays a role in affecting smooth muscles, relaxing them to allow blood vessels to dilate and increase blood flow to certain areas of the body.
Beets are rich in dietary nitrates, which your body can convert to nitric oxide.
Garlic, meat, dark chocolate, leafy greens, citrus fruits, pomegranate, nuts, and seeds.
Carbon monoxide
Produced naturally by the body where it acts as a neurotransmitter that helps modulate the body's inflammatory response.
- -

Acts as both a hormone and a neurotransmitter. It is produced by the hypothalamus and plays a role in social recognition, bonding, and sexual reproduction.

Figs, avos & green tea
These are neurotransmitters that inhibit the transmission of pain signals and promote feelings of euphoria. These chemical messengers are produced naturally by the body in response to pain, but they can also be triggered by other activities such as aerobic exercise.
strawberries, animal proteins, oranges, spicy foods, grapes, nuts and seeds, ginseng.


Integrative & Functional Medicine

Genotyping and nutrition should be used as part of the overall treatment of mood and stress by healthcare practitioners. This integrative approach establishes a triad between your nutrition, GUT health, and brain and empowers you with the right tools for your body and neurotransmitter profile.

To get a good overview, visit our integrated MIND SHOP.

And just remember, biology gives you a brain. Your life turns it into a mind. 

Marguerite Doig-Gander
BA (Speech, Hearing & Lang Therapy) Hons | FMCHC | ReCODE Coach | Men's Health |  HMX Genomics & Biochemistry (Candidate)  

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