A Biologist Explains Why Humans Have Earwax (Hint: Some People Can’t Make It)

Most people think earwax is just something to clean out, but biologists say it's a sophisticated antimicrobial secretion with two genetic types—and some people are genetically unable to produce it at all. A new article by biologist Scott Travers on Forbes explains that earwax is not dirt but a protective secretion that can reveal insights about hearing loss risk and even help detect a rare disease in newborns.

Earwax, or cerumen, is produced by glands in the ear canal. Its primary job is to trap debris, prevent infection, and keep the ear canal lubricated. For decades, scientists have known that earwax comes in two forms: wet (sticky, yellowish) and dry (flaky, grayish). These types are determined by a single gene, ABCC11. Wet earwax is dominant and common in people of European and African descent. Dry earwax is recessive and predominant among East Asian populations.

The Forbes piece highlights a lesser-known fact: some individuals carry a genetic variant that prevents them from making earwax at all. This complete absence can be an early red flag for rare inherited disorders, including cystic fibrosis and primary ciliary dyskinesia. The article reports that pediatricians are now trained to check for earwax absence during newborn exams as a quick, non-invasive screening tool.

But the story doesn't end with infancy. Earwax genetic types are also linked to hearing health. Wet earwax contains higher concentrations of antimicrobial peptides, offering stronger protection against infections that could damage hearing. Conversely, dry earwax has lower antimicrobial activity, potentially raising the risk of chronic ear infections and hearing loss. Researchers are exploring whether earwax typing could become a routine part of audiology assessments.

The analysis of earwax genetic types is part of a broader shift toward using bodily secretions as windows into health. Unlike blood tests, earwax is easy to collect and analyze. Its chemical composition reflects a person's metabolic and genetic profile. Some scientists have even proposed using earwax to measure cortisol levels for stress monitoring. The Forbes article underscores that something as humble as earwax can carry life-altering clues.

Looking ahead, the medical community is likely to invest more in earwax research. Clinical trials are needed to correlate earwax types with specific disease risks, especially hearing loss and rare genetic conditions. As genetic sequencing becomes cheaper, routine screening for ABCC11 variants could become standard in pediatric care. Earwax, once dismissed as a nuisance, may soon be a biomarker that saves hearing—and lives.