You React to Everything. Your Genes May Explain Why.

GSTM1 encodes an enzyme that performs one of the most critical detoxification tasks in your body: conjugating toxins to glutathione so they can be excreted. It handles a wide range of environmental threats, including solvents, pesticides, heavy metals, and carcinogens. This enzyme works in your liver, kidneys, and immune cells.

Approximately 50% of people carry a GSTM1 gene deletion, meaning they produce no GSTM1 enzyme at all. If you’re in this group, you’ve lost roughly 50% of one of your primary detoxification pathways. Toxins that should be quickly conjugated and eliminated instead accumulate in your tissues, triggering inflammatory responses and systemic symptoms.

You likely notice that exposures others handle without reaction set off your symptoms. Pesticide spraying in a park, sitting near someone wearing certain fragrances, exposure to new construction materials, or time spent in moldy spaces leaves you symptomatic for days. Your body is working overtime trying to process what your detox system cannot efficiently handle.

GSTP1 is another Phase II detoxifier, but with a different specialty: it clears oxidative stress byproducts and electrophilic compounds. When your cells burn energy or respond to inflammatory signals, reactive oxygen species are created as a byproduct. GSTP1 binds these dangerous molecules to glutathione so they don’t damage your DNA or proteins. It also helps clear environmental pollutants and heavy metals.

The Ile105Val variant is carried by roughly 35-40% of the population. People with the Val allele have reduced GSTP1 enzyme activity, meaning oxidative stress accumulates faster in response to environmental exposures. Your antioxidant defense is slightly slower than normal, so toxins and free radicals linger longer in your cells.

You may notice that chemical exposures leave you with oxidative stress symptoms: brain fog, joint pain, muscle fatigue, or a flare in systemic inflammation. These aren’t separate problems. Your cells are struggling to manage the byproducts of trying to process the toxin load.

GSTT1 handles a specific class of toxins: organic compounds including solvents, disinfection byproducts, and certain pesticide metabolites. It’s particularly important for clearing chlorinated compounds found in tap water, bleach, and industrial processes. Unlike GSTM1, which most people have, GSTT1 is deleted in roughly 15-20% of people with European ancestry.

If you carry the GSTT1 null genotype, you have minimal or no capacity to clear these specific toxins. You’re genetically predisposed to accumulate solvents, chlorine compounds, and disinfection byproducts that others eliminate without issue. This is especially significant because these compounds are everywhere: in tap water, cleaning products, swimming pools, and newly constructed buildings.

You probably notice reactions to very specific triggers: the smell of bleach or new furniture lingers as brain fog and headache, swimming in chlorinated pools triggers respiratory symptoms or fatigue, or using standard cleaning products makes your eyes water and your lungs tight. These aren’t overreactions. Your detox system has a specific gap that’s being hit.

MTHFR is the central hub of your methylation cycle, the biochemical process that powers detoxification, DNA repair, and immune regulation. It converts folate into its active form, methylfolate, which is then used to generate S-adenosyl methionine (SAM). SAM is the currency your cells use for hundreds of critical reactions, including the synthesis of glutathione, your body’s master antioxidant and detoxifier.

The C677T variant is carried by approximately 40% of people with European ancestry and reduces MTHFR enzyme efficiency by 30-40%. If you have this variant, your methylation cycle is slower, which means you produce less glutathione and have reduced capacity to methylate and eliminate heavy metals and environmental toxins. Your detoxification is constrained not just in Phase II, but upstream in the system that generates the cofactors Phase II needs.

You experience this as a compounding problem: environmental exposures that others might handle you accumulate because your glutathione production is impaired. You may also notice that you’re more sensitive to methylation-dependent problems like histamine accumulation, hormonal imbalance, and impaired DNA repair. Environmental toxins pile on top of impaired detox capacity.

SOD2 is an antioxidant enzyme that lives inside your mitochondria, the power plants of your cells. It converts superoxide, a dangerous free radical, into hydrogen peroxide, which is then neutralized by catalase. This is your first line of defense against oxidative stress. Without efficient SOD2, oxidative damage accumulates inside your mitochondria, damaging DNA, proteins, and the energy production machinery itself.

The Val16Ala variant is common, with roughly 40% of European ancestry people homozygous for the variant allele. People with this variant produce less SOD2 enzyme, so oxidative stress accumulates faster inside your mitochondria when you’re exposed to toxins, pollution, or heavy metals. Your cellular power plants are being damaged at a higher rate.

You experience this as fatigue that doesn’t respond to sleep, exercise intolerance, slow recovery from illness or chemical exposures, and a feeling that environmental stressors drain your energy disproportionately fast. Because your mitochondria are being damaged, your cells can’t generate the energy needed to support detoxification. It becomes a vicious cycle: toxins accumulate because you lack energy to clear them, and you lack energy because toxins are damaging your mitochondria.

TNF is a signaling molecule your immune cells release to trigger inflammatory responses. In appropriate doses, inflammation is protective: it kills infections and removes damaged cells. But TNF is also primed to overreact to environmental triggers. The -308G>A variant changes how much TNF your immune cells produce in response to stimulation.

Approximately 30% of people carry the A allele at this position. If you’re in this group, your immune system produces more TNF in response to environmental exposures, meaning your inflammatory response is amplified. Mold spores that should trigger a mild immune alert instead trigger a strong inflammatory cascade. Chemical odors activate a disproportionate TNF surge. Your immune system is set to a higher sensitivity.

You experience this as exaggerated reactions to mold-contaminated spaces, chemical sensitivity that manifests as respiratory symptoms or systemic inflammation, and an overall pattern of feeling worse in environments others find unremarkable. Your immune system isn’t broken. It’s just configured to react more strongly, and that configuration is genetic.