COMT rs4680 (also called Val158Met) is a single nucleotide polymorphism in the COMT gene that substitutes methionine (Met) for valine (Val) at amino acid 158. COMT is a phase II methyltransferase that uses S-adenosylmethionine (SAMe) to add methyl groups to catechol substrates, including dopamine, norepinephrine, epinephrine, and catechol-derived estrogen metabolites. The functional effect of rs4680 is well characterized: the Met variant produces a form of COMT with reduced thermostability and lower enzymatic activity compared with the Val form. This biochemical difference links the variant to measurable variation in neurotransmitter turnover, estrogen metabolite profiles, and interactions with broader methylation genetics and nutrient status.

Interpreting COMT rs4680 focuses on relative COMT activity rather than a single biochemical “level.” A genotype associated with higher COMT activity (Val/Val) corresponds to faster methylation and clearance of catecholamines and catechol estrogens, which can be associated with patterns like lower synaptic catecholamine availability in some brain regions and altered estrogen metabolite balance. A genotype associated with lower COMT activity (Met/Met) corresponds to slower methylation and greater local availability of catecholamines and catechol estrogens, potentially relating to different stress reactivity, pain sensitivity, or estrogen metabolite patterns. These associations are context dependent: COMT effects interact with other methylation genes (e.g., MTHFR), nutrient status (folate, B12), hormone levels, and inflammatory or metabolic markers measured across the Foundation Zoomer. Genotype interpretation should be integrated with the full panel and clinical history.

COMT rs4680 is included in the Foundation Zoomer’s methylation genetics module to clarify individual methylation capacity for catechol substrates and to contextualize neurotransmitter and estrogen metabolism. The genotype helps providers see how genetic methylation potential may interact with nutrient status, hormone results, and other system-level markers to refine personalized care planning.