Body Odor May Smell Much Worse For Your Ancient Ancestors

When you breathe something, odor molecules navigate inside your nose where they bind to proteins – called olfactory receptors – on the ...

When you breathe something, odor molecules navigate inside your nose where they bind to proteins – called olfactory receptors – on the cells that line your nasal cavity. These receptors trigger signals that your brain interprets as one or more smells.

A team of scientists have identified the olfactory receptors for two common odor molecules: a musk found in soaps and perfumes and a compound important in smelly armpit sweat. The research team also found that more recent evolutionary changes to these olfactory receptors make people less sensitive to these smells. So if you’re one of the lucky ones who isn’t overwhelmed by body odor, you probably have evolution to thank. The book was published in PLoS Genetics Thursday.

Olfactory receptors date back hundreds of millions of years and are thought to be present in all vertebrates. Humans have around 800 olfactory receptor genes, but only about half of them are functional, which means they will be translated into proteins that hang around in the nose and detect odor molecules. But within a functional gene, minor variations can cause changes in its corresponding receptor protein, and these changes can massively affect how an odor is perceived.

“There is a molecule called androstenone,” noted Joel Mainland, a neuroscientist at the Monell Chemical Senses Center and author of the new study. “And we know that some people smell this molecule like urine, some people smell this sandalwood molecule, and some people don’t smell it at all.”

That said, genetic changes aren’t the only thing underlying scent interpretation. “One is genetics and the other is experience, which includes things like the culture you grew up in,” said Hiroaki Matsunamia molecular biologist from Duke University who was not involved in the research but whose work focuses on olfaction.

The study conducted by Dr. Mainland and his colleagues was a collaborative effort between scientists in the United States and China. They sequenced the genomes of 1,000 people in Tangshan, China, who are members of the Han ethnic group. They did the same with an ethnically diverse cohort of 364 people in New York. Participants were asked to rate, on a 100-point scale, the intensity and pleasantness of a range of common odors. The researchers then looked for associations between olfactory receptor genes and odors as well as variations within these genes and their potential impact on odor perception.

By sampling a large, diverse population of people, the researchers were able to focus on smells whose perception was based on genetic differences between people, rather than cultural or experiential factors. This led them to molecules such as trans-3-methyl-2-hexenoic acid and galaxolide.

Trans-3-methyl-2-hexenoic acid is considered one of the most pungent compounds in armpit sweat. Galaxolid is a synthetic musk often described as having a floral, woodsy smell that is used in perfumes and cosmetics, but also in things like kitty litter. The research team was able to identify olfactory receptor variants for these smells, and in both cases, people with the most evolutionarily recent genetic variant found the smells to be significantly less intense.

The galaxolide findings were particularly striking, with some participants unable to smell musk at all. “It’s really rare to find such a large effect as what we saw for this receptor on the perception of musk odor,” said Marissa Kamarcka University of Pennsylvania neuroscientist who was one of the study’s authors.

Dr. Matsunami sees this work as another example of human olfaction being more complex than people initially thought. He said that although the main results of the study were for only two fragrances, they are add to proof that “odorant receptors as a group have extraordinary variety”.

The authors believe their findings confirm a hypothesis this was criticized that the olfactory system of primates has degenerated during evolution. Kara Hooveran anthropologist from the University of Alaska Fairbanks who was not involved in this research but who studies the evolution of the human sense of smell, is not convinced by this hypothesis in the first place.

“Why is a reduced intensity supposed to be a degradation? ” she asked. “Maybe other things are getting more intense or the discrimination of smells is getting better. We know too little to draw those conclusions.

For Dr. Hoover, these findings raised further evolutionary questions. “Our species is really young,” she said. “Why so many variations in such a short time? Is there adaptive significance? »

Source Link



Africa,957,Americas,4374,Art & Culture,16176,Arts,6814,Arts & Design,1919,Asia,3599,Automobile,572,Baseball,836,Basketball,682,Books,4228,Business,5705,Celebrity,2633,Cricket,648,Crime,158,Cryptocurrency,2165,Dance,715,Defense,836,Diplomatic Relations,2496,Economy,1394,Editorial,260,Education,1514,Elections,308,Energy & Environment,3190,Entertainment,23696,Environment,3970,Europe,4557,Faith & Religion,235,Family & Life,817,Fashion & Style,3670,Finance,21880,Food & Drink,4144,Football,1311,Games,97,Gossip,10289,Health & Fitness,4495,Health Care,967,Hockey,271,Home & Garden,920,Humour,994,Latin America,49,Lifestyle,18576,Media,527,Middle East,1758,Movies,2053,Music,2979,Opinion,4079,Other,13209,Other Sports,5484,Political News,11324,Political Protests,2324,Politics,18863,Real Estate,2305,Relationship,106,Retail,3116,Science,2975,Science & Tech,11192,Soccer,382,Space & Cosmos,450,Sports,13588,Technology,3797,Tennis,729,Theater,1970,Transportation,313,Travel,2853,TV,4023,US,1565,US Sports,1481,Video News,3531,War & Conflict,1069,Weird News,998,World,18218,
Newsrust - US Top News: Body Odor May Smell Much Worse For Your Ancient Ancestors
Body Odor May Smell Much Worse For Your Ancient Ancestors
Newsrust - US Top News
Loaded All Posts Not found any posts VIEW ALL Readmore Reply Cancel reply Delete By Home PAGES POSTS View All RECOMMENDED FOR YOU LABEL ARCHIVE SEARCH ALL POSTS Not found any post match with your request Back Home Sunday Monday Tuesday Wednesday Thursday Friday Saturday Sun Mon Tue Wed Thu Fri Sat January February March April May June July August September October November December Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec just now 1 minute ago $$1$$ minutes ago 1 hour ago $$1$$ hours ago Yesterday $$1$$ days ago $$1$$ weeks ago more than 5 weeks ago Followers Follow THIS PREMIUM CONTENT IS LOCKED STEP 1: Share to a social network STEP 2: Click the link on your social network Copy All Code Select All Code All codes were copied to your clipboard Can not copy the codes / texts, please press [CTRL]+[C] (or CMD+C with Mac) to copy Table of Content