Asparagus urine odor detection

A cluster of smell-receptor genes decides whether you can detect the distinctive sulfur smell in urine after eating asparagus. Some people simply can't smell it.

Possible results

Can't smell asparagus odor. You carry the version near these smell receptors linked to not detecting asparagus pee, the distinctive smell some people notice in urine after eating asparagus. You may simply not smell it, even though your body still makes the odor.

Can smell asparagus odor. You carry one copy of the variant that lets you detect the asparagus urine smell, so you can probably smell it after eating asparagus. It's purely about your nose, not your kidneys.

Can smell asparagus odor. You have two copies of the variant tied to smelling asparagus pee, so you almost certainly notice the distinctive odor in urine after eating asparagus. Everyone's body makes the smell; this gene is about whether your nose picks it up.

Evidence & sources

Across global populations, about 5% of people carry two copies of this variant, and about 64% carry none.

This variant appears in 1 published genetic study: PubMed 20585627.

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