Dry Earwax and Less Underarm Odor: The ABCC11 Gene Explained

Earwax comes in two types: wet (sticky, yellow-brown) and dry (flaky). The difference comes down to one letter of DNA, and that same letter helps decide how much your underarms smell.

One gene, two traits

In 2006, researchers traced earwax type to a variant in a gene called ABCC11.¹

• Two copies of the “A” version: dry earwax.¹
• One or two copies of the “G” version: wet earwax.¹

The A version is most common in Chinese and Korean people and becomes rarer moving away from northeast Asia.¹

The link to underarm odor

ABCC11 is active in the apocrine sweat glands of the armpit, the glands behind body odor.² In people with two A copies, those glands release almost none of the odorless building blocks that skin bacteria turn into the typical underarm smell.²

Genotype	Underarm odor
AA (dry earwax)	Much lower, but still noticeable to human smellers3
GA or GG (wet earwax)	Typical odor3

Every genotype still produced some smelly fatty acids.³ So “low odor” doesn’t mean “no odor.” The 2014 study included scientists from a personal-care company.³

Habit versus biology

A British study of about 17,000 people checked the gene against deodorant use.⁴ People with the low-odor AA genotype were almost 5 times more common among those who rarely or never used deodorant.⁴ Yet 78% of white Europeans with the low-odor genotype used deodorant anyway, and about 5% of people with the higher-odor genotype didn’t.⁴

Habit and social expectation seem to drive deodorant use as much as smell does.

What this means for you

• Your earwax isn’t a home test. The link holds across groups, but it can’t tell you how you smell.
• Your neighbor’s routine fits her chemistry, not yours. Track your own pattern before buying stronger products.
• Deodorant targets smell; antiperspirant targets wetness. See antiperspirant or deodorant.
• A sudden change in your smell is worth mentioning to a doctor; see can illness change your body odor?

Try: “I barely sweat or smell under my arms and have dry earwax. Is there any reason I need to use deodorant at all?”

Arms Up covers this in Chapter 4, “Sweat Doesn’t Smell,” which traces odor from scentless secretion to bacteria to genes. Its Fresh Log records where and when you smell, so your routine is built for your body rather than someone else’s. See the book.