A nonsynonymous single nucleotide polymorphism (SNP), rs17822931-G/A (538G>A; Gly180Arg), in theABCC11 gene determines human earwax type (i.e., wet or dry) and is one of most differentiated nonsynonymous SNPs between East Asian and African populations.
Based on the near-ubiquity of the recessive dry form of the gene in Korea and northern China, the authors concluded that this mutation must have originated in northern Asia following the migration from Africa, and suggested that it may have been an adaptation to a colder climate.
Dry earwax, typical in East Asians and Native Americans, is light-colored and flaky, while earwax found in Caucasian and African groups is darker, wetter and, a new study shows, smellier.
Earwax type: The myth
The allele for dry earwax appears to have originated by mutation in northeastern Asia about 2,000 generations ago, then spread outwards because it was favored by natural selection. It is very common in eastern Asia, becomes much less common towards Europe, and is very rare in Africa.
East Asian and Native American people were already known to have a form of the ABCC11 gene that causes the dry type of earwax and produces less underarm body order, compared with other ethnicities.
Dry earwax is very common (80–95 per cent of the population) among east Asians, but is less frequent (30–50 per cent) in southern Asia, the Pacific Islands, central Asia and Asia Minor, and in native North Americans and Inuit peoples of Asian ancestry. It's very uncommon among Europeans and Africans (0–3 per cent).
Earwax comes in two types, wet and dry. The wet form predominates in Africa and Europe, where 97 percent or more of the people have it, and the dry form among East Asians, while populations of Southern and Central Asia are roughly half and half.
Most of the world's population has the gene that codes for the wet-type earwax and average body odor; however, East Asians are more likely to inherit the allele associated with the dry-type earwax and a reduction in body odor.
In contrast, about 97% to 100% of people with European and African ancestry have the smelly-armpit version of the gene, and therefore stickier and smellier earwax. Thirty to fifty percent of South Asians, Central Asians, and Pacific Islanders have the dry type of earwax.
Wet/dry types of earwax are determined by the c. 538G>A single-nucleotide polymorphism (SNP) in the ABCC11 gene; GA and GG genotypes give the wet type and AA the dry type. The Japanese population may have a dual structure comprising descendants of mixtures between the ancient 'Jomon' and 'Yayoi' populations.
Smelly genes
"This key gene is basically the single determinant of whether you do produce underarm odor or not," Day said. While only 2 percent of Europeans lack the genes for smelly armpits, most East Asians and almost all Koreans lack this gene, Day told LiveScience.
Ear picks, also called ear scoops, or ear spoons, or earpicks, are a type of curette used to clean the ear canal of earwax (cerumen). They are preferred and are commonly used in East Asia, South Asia and Southeast Asia because Asians tend to develop dry ear wax.
The type of earwax you have doesn't really say anything about your ears. “Whether it's wet or dry and even the color...has no implication for the ear health of the person,” Nina Shapiro, M.D., otolaryngologist at UCLA Health, tells SELF. Instead, the type of earwax you have comes down in part to your skin type, Dr.
The lucky "dry earwax" people don't produce the protein, so they don't make the apocrine underarm sweat that attracts bacteria (it's worth noting we produce two types of sweat, the other being body-wide ecrine sweat, salty water, which isn't affected by this gene).
While cotton swabs are the norm in the West, in many parts of East Asia, it's common to use ear scoops – a long, thin tool with one tip flattened into a little spoon – to tease out excess ear wax.
But cultural differences and simple biology — scientists have shown that many East Asian people don't have Westerners' body odor issues — scotched those plans.
30-50% of South Asians, Central Asians and Pacific Islanders have the dry type of cerumen.
Although there is some controversy on the subject of "racial" variation in body odor, it is determined that African blacks probably produce the greatest amount of apocrine sweat, which is the known substrate for axillary odor.
For example, a major contributor to axillary odor, E-3M2H, was significantly higher in African-Americans when compared to Caucasians. In addition, there were significant differences across donor groups in the number of individuals who produced detectable levels of 3H3M, with African-American > Caucasian > East Asian.
Two percent of people carry an unusual form of a specific gene (ABCC11) that means their armpits never smell.
It's wet, brown and gummy in nearly all people of European and African origin; but more than 80% of East Asians have a dry variety that lacks a waxy substance called cerumen. A team of Japanese researchers has now tackled this sticky subject and identified the gene that determines earwax type.
Your earwax type is linked to your origins. Dry earwax first appeared in Asia and is thus more common among Asian and Native American populations. Wet earwax is common among most other populations. Scientists still aren't sure why Asian and Native American populations' earwax is different from the rest of the world's.
Some people (such as Europeans and Africans) sweat a reasonable amount, and they tend to have wet earwax. And some people (such as Koreans and Chinese) don't sweat much at all, and they tend to have dry earwax. Earwax is manufactured inside your ear canal.