Opioid Response

Your result, the one DNA position behind it, and what the research says.

9/10 confidence.

About Opioid Response

OPRM1 builds the mu-opioid receptor, the main target for both your body's own endorphins and opioid drugs. This variant slightly reshapes the receptor and has been studied for links to pain sensitivity, how people respond to opioid painkillers, and alcohol craving. Evidence for these links is limited, so any single person's effect is uncertain - for anything involving pain or medication, your doctor and your own experience are the right guide.

Good to know: For anything involving pain or medication, your doctor and your own history come first. Results differ a lot between studies, so read this lightly. The same receptor handles both your natural endorphins and opioid drugs.

Fun fact: This receptor is where both morphine and your body's own 'runner's-high' endorphins act.

Discovery: This variant's effects on opioid signaling were described in the late 1990s.

The Variant

The single variant behind this trait

Gene: OPRM1

Variant (rsID): rs1799971

Location: Chr 6:154,039,662

dbSNP rs1799971

The studies

OPRM1 A118G gene variant and postoperative opioid requirement: a systematic review and meta-analysis (Hwang IC et al., Anesthesiology, 2014)

Allelic expression imbalance of human mu opioid receptor (OPRM1) caused by variant A118G (Zhang Y et al., The Journal of biological chemistry, 2005)

Other lifestyle traits

Galactose Handling: A common change in GALT, the enzyme that processes galactose, half the sugar in milk. It marks a lower-activity version without settling whether you carry it.

Histamine Clearance: A change in diamine oxidase, the gut enzyme that breaks down histamine arriving in food, affecting how quickly you clear it.

Secretor Status: A change that decides whether you secrete your blood group antigens into saliva, tears and gut fluid, which shapes the bacteria your gut hosts.

Back to All Traits

Content updated September 2026.

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