How many of your patients ask, “Why do I get so much earwax? How come it’s always wet or dry, or rice like? Is there really a racial implication to cerumen and, if so, then wax types and consistency could be different in various parts of the world.
As audiologists we all know that cerumen is secreted by the ceruminous apocrine glands in the outer 1/3 of the ear canal. As clinicians, we go to great lengths to facilitate the safe removal of cerumen. Although many audiologists around the world have great skill in cerumen management, in some countries removal methods can be draconian, bazaar, unsanitary, and even erotic (Traynor, 2010).
For many years the journals have told us that there are some racial implications in the type and consistency of cerumen. Thus, if you go to various parts of the world you will not only encounter various methods of removal, but also different types and consistency of wax depending upon the racial makeup of the population. Carey (2006) indicates that earwax has been linked to your heritage and its wetness or dryness is determined by a mutation in a single gene.
Earwax Research: Ethnic Differences in Type & Consistency
An international team of researchers studied the genes of people from 33 populations across the world and found ethnicity effects. Yoshiura et al (2006) indicates that human earwax consists of wet and dry types. Dry earwax is frequent in East Asians, whereas wet earwax is common in other populations.
In their research they identified the specific genes that are responsible for earwax and investigated why there were different types. Yoshiura and colleagues are very specific as to which genes and variations are responsible, they suggest that a specific gene alters the shape of a channel that controls the flow of molecules directly affecting earwax type.
They also found in East Asians, a mutation of the gene that prevents the molecule that makes earwax wet, from entering the mix. BBC News (2006) summarized the Yoshiura et al (2006) study suggesting that dry earwax is seen in up to 95% of East Asians, but in no more than 3% of people of European and African origin. Populations in Southern Asia, the Pacific Islands, Central Asia, Asia Minor, and Native North Americans and those of Asian ancestry, fall in the middle with dry wax incidence ranging from 30 to 50 percent.
Smelly Earwax?
Do you have the stinky type? Yoshiura and colleagues suggest that the answer is partly in your heritage. They also raised the unlikely possibility that earwax type could be linked to attractiveness, due to a link with body odor glands.
References
BBC News (2006). Racial differences in earwax. Modern Tribalist. Retrieved from the World Wide Web, April 13, 2011: http://moderntribalist.blogspot.com/2006/01/racial-differences-in-earwax.html
Carey, B., (2006). Is your earwax wet or dry? Live Sciences, Retrieved from the World Wide Web, April 13, 2011: http://www.livescience.com/593-earwax-wet-dry.html
Traynor, R. (2010). Cerumen Management in the Third World. Hearing Aid Journal blog. Retrieved from the World Wide Web, April 13, 2011: http://journals.lww.com/thehearingjournal/HearingPost/MyForeignAffairs/Pages/default.aspx
Yoshiura A, et al (2006). A SNP in the ABCC11 gene is the determinant of human earwax type. Nature Genetics 38, 324 – 330 (2006). Retrieved from the World Wide Web April 13, 2011: http://www.nature.com/ng/journal/v38/n3/full/ng1733.html
