Your pain is getting worse. Your genes may be the reason.

COMT is an enzyme that clears catecholamines (dopamine, norepinephrine, epinephrine) from your brain and nervous system. These chemicals are critical for downregulating pain signals. When COMT works normally, it clears these pain-modulating chemicals at the right speed, allowing your nervous system to reset and suppress pain sensation.

The Val158Met variant, carried by roughly 25% of the population in homozygous slow form, impairs COMT’s activity. Slow COMT means your brain can’t efficiently clear pain-signaling chemicals, so pain signals linger longer and feel more intense. Your nervous system gets stuck in pain amplification mode.

If you have slow COMT, normal pain feels worse. Chronic pain feels unbearable. Your nervous system is hypersensitive to any stimulus that would normally trigger dopamine or norepinephrine release. Stress, cold, noise, and movement all feel more painful because your brain can’t reset the pain signal quickly enough.

OPRM1 codes for the mu-opioid receptor, which is your body’s primary mechanism for experiencing natural pain relief. When you exercise, laugh, or feel safe, your brain releases endogenous opioids (endorphins, enkephalins) that bind to mu-opioid receptors and suppress pain. This is your built-in analgesia system.

The A118G variant, carried by roughly 10 to 15% of people in European ancestry (much higher in East Asian populations), reduces your opioid receptor’s sensitivity to these natural painkillers. Your endogenous opioids are less effective at blocking pain signals, so your natural pain relief capacity is weaker. You literally have fewer functional pain-suppression tools at your disposal.

If you have the G allele, you feel pain more acutely because your opioid system is less responsive. Physical activity, which would normally trigger endorphin release and pain relief in others, may provide you little benefit. Pleasure, laughter, and social connection (all opioid-mediated) may feel less pain-relieving than they do for others. You need non-opioid pain management strategies.

MTHFR is an enzyme that drives the methylation cycle, which is essential for producing nitric oxide (a neurovascular regulator) and for maintaining myelin (nerve insulation). Impaired methylation disrupts both pain signaling and vascular tone in pain-sensitive tissues.

The C677T variant, carried by roughly 40% of the population, reduces MTHFR activity by 40 to 70%. This impairs nitric oxide production and raises homocysteine, both of which increase pain sensitivity and nerve inflammation. Your blood vessels constrict more easily, oxygen delivery to nerves worsens, and pain neurons fire more readily.

If you have MTHFR C677T, you likely experience pain that worsens with stress (poor nitric oxide production), pain that’s worse in cold (vascular constriction), and pain that increases with B vitamin deficiency (because your methylation cycle can’t process dietary folate efficiently). Flare-ups often involve vascular components: throbbing, burning, or shooting sensations.

BDNF (brain-derived neurotrophic factor) is a protein that regulates how your neurons communicate and how quickly your nervous system strengthens pain pathways (central sensitization). In healthy doses, BDNF supports learning and resilience. At high levels in pain neurons, BDNF drives the nervous system into chronic pain mode.

The Val66Met variant, carried by roughly 30% of the population, alters how BDNF is released in response to pain and stress. The Met allele is associated with higher pain sensitization and stronger establishment of chronic pain pathways. Your nervous system learns pain more quickly and forgets it more slowly.

If you have BDNF Val66Met, your pain tends to worsen with repetition and stress because your nervous system is building stronger pain memories. Acute pain becomes chronic more easily. Flare-ups become more severe because your brain has already created robust pain pathways. Physical therapy or exercise that would help others may actually reinforce pain in you if not carefully dosed.

GCH1 encodes the enzyme that produces tetrahydrobiopterin (BH4), which is an essential cofactor for three critical neurotransmitters: serotonin, dopamine, and nitric oxide. Without adequate BH4, your body cannot produce enough of these pain-modulating chemicals even if you have all the precursors available.

GCH1 variants, carried by roughly 15 to 20% of the population, reduce BH4 production. Lower BH4 means your body cannot efficiently synthesize serotonin, dopamine, or nitric oxide, so your natural pain suppression systems are constrained at the chemical level. No amount of tryptophan, L-tyrosine, or L-arginine supplementation can fix this if BH4 is the bottleneck.

If you have GCH1 variants, pain sensitivity is higher across the board. Your nervous system lacks the chemical substrate to downregulate pain. Stress sensitivity is heightened. Sleep is often disrupted (serotonin and dopamine both regulate sleep). Mood is frequently low (dopamine insufficiency). These symptoms often cluster together in people with GCH1 variants.

FAAH is an enzyme that breaks down anandamide, the body’s endogenous cannabinoid. Anandamide is a powerful analgesic that activates CB1 receptors in the brain and spinal cord to suppress pain signals. The more anandamide available, the more pain relief you get from this system.

The C385A variant, carried by roughly 20 to 30% of the population, reduces FAAH activity. The A allele means your body breaks down anandamide more slowly, so you maintain higher anandamide levels and experience more endocannabinoid-mediated pain relief. This is a genetic advantage for pain sensitivity.

If you have the A allele, you have a built-in protective factor against pain. Your nervous system has a more powerful brake on pain signals. However, this advantage can be lost if you deplete anandamide through chronic stress, poor sleep, or inflammatory diet. Conversely, if you don’t have the A allele, you may need external support to maintain adequate anandamide (cannabis, CBD, or anandamide precursors).