Earwax type / body odor

A single change in the ABCC11 gene sets whether your earwax is wet or dry and how strong your underarm odor tends to be. It's one of the few traits decided by essentially one gene.

Possible results

Wet earwax. You have two copies of the common wet version of ABCC11, so your earwax tends to be sticky and moist. The same gene drives underarm sweat chemistry, so you're also more likely to have noticeable body odor (nothing washing can't handle).

Wet earwax. You carry one wet and one dry copy of ABCC11. The wet version wins out, so your earwax is likely the sticky type and your body odor is in the typical range.

Dry earwax, low odor. You have two copies of the dry version of ABCC11, so your earwax is the dry, flaky type. The same variant also means your underarms make less of the compounds behind body odor, so you probably have little to none. This pattern is common in East Asia.

Evidence & sources

Across global populations, about 5% of people carry two copies of this variant, and about 72% carry none.

Related

Freckling / sun sensitivity · Hair thickness / shovel-shaped incisors · Height · Male-pattern baldness tendency · Muscle fiber type (power vs endurance) · Red hair / fair skin (MC1R gene) · Skin pigmentation (light vs dark)