COVID-19 and Loss of Smell

Many individuals diagnosed with COVID-19 typically also suffer from the loss of taste or smell. According to an article, researchers have now pinpointed the genetic variants in humans suffering from losing different senses. A study was conducted with nearly 70,000 adults with COVID-19 and found that individuals with specific genetic mishaps on chromosome 4 were eleven percent more likely to lose the ability of their senses, whether taste or smell, than those individuals without the changes on their chromosome. The two genes, UGT2A1, and UGT2A2, help humans smell and happen to reside in the region of chromosome 4 that is linked to sensory loss during infection, found by Janie Shelton of 23andMe. Both of these genes make enzymes that metabolize substances called odorants, producing distinctive smells. 

For me, when I had covid, I lost my sense of smell, and I know a few other individuals and family members who have as well. I also do remember that news reports did suggest that one of the symptoms of COVID-19 is losing the sense of smell but I never heard of anyone loosing their sense of taste. When being sick many people loose their sense of taste especially if one has a sore throat. I believe more research may have to go into this study to se exactly how we loose our smell or taste for some individuals. 

Can you smell ants too?

 Scrolling on TikTok until five a.m. might not be great, but at least it can teach you some things.

Like the fact that some people can smell ants??

After a video sparked a debate on TikTok, people started wondering whether it was actually possible to smell tiny little ants. And yes, it is. According to Clint Penick, an ant researcher and assistant professor at Kennesaw State University, ants release a pungent smell when in danger or dead. One of these specific smells is formic acid sprayed by carpenter ants which are a very common house ant. It is believed by some that the ability to smell ants is genetic, leading people to conclude that as the reason some people smell this scent on ants more than others. I've never really thought of smelling an ant to pinpoint a smell's location, but next time I see one, I might have to...

So can you smell ants?

Can you smell fishy odors?

 According to an article posted by the NY Times, some people have a mutation that makes them not smell the common fish smell. Dr. Stefansson, founder of deCODE genetics, conducted a study where people were they asked participates to smell six pens with synthetic odors. A small group thought the fish smell, was actually caramel scented. This mutation effects the TAAR5 gene. This mutation actually appears more common in Icelanders, which they have not figured out why yet. In my opinion this discovery is very unique. Normally when people think of mutation, they think of something being physical or mental wrong with someone, when in relative the severity ranges. Not being able to smell fishy scent may be better, at least I wish I didn’t smell them.

Addition article with information: https://www.nature.com/articles/d41586-020-02832-1#:~:text=When%20exposed%20to%20the%20reek,fish%20can%20smell%20like%20caramel

There's a Gene For Detecting That Fishy Smell, Olfactory GWAS Shows

 

Science researchers have discovered that there are genes for specific smells that not everyone have. The most popular tests they have done would be fish, licorice, and cinnamon. The gene trace amine-associated receptor 5 (TAAR5) is an olfactory receptor responsible for the fishy smell. Personally, I could go without this receptor and some are lucky enough not to smell fish, unfortunately most of us can. researchers say that people who have this gene do not have a strong sensitivity to the smell of fish, while others who don't have this gene do have a strong sensitivity to the smell. Likewise, carriers of the gene were able to accurately name and describe the intensity of the smell much more accurately than those who are not carriers. This all ties in with human perception as well as behavior. With this study, researchers and scientists are looking for ways to use these receptors to smell COVID-19 on people. This way dogs are able to sniff out people who have contracted COVID-19. This would be very interesting for the future and I am excited to see what comes of it.

https://medicalxpress.com/news/2020-10-gene-fishy-olfactory-gwas.html

https://www.sciencedaily.com/releases/2019/04/190430164208.htm#:~:text=Small%20differences%20in%20olfactory%20receptor,another%20smells%20nothing%20at%20all.

Why Do Bearcats Smell Like Popcorn?

Many of us don't know what a bearcat is let along have seen one, but these unique animals are neither bear nor cat. They are native to Southeast Asia and the bearcat has a very amusing fact about them, and that is they apparently smell like buttered popcorn. A team of scientist from the Carolina Tiger Rescue believe they have cracked the mystery as to why the bearcat smells like popcorn and where the smell comes from. The compound that they found that is responsible for the smell is also found it real popcorn itself surprisingly enough. Scientists originally believed the compound/smell came from a sent gland at the base of the bearcat's tail but when they tried to locate the compound they came up with nothing.



It wasn't until they were checking the urine samples of bearcats at a American nature reserve, that the team of scientists found what they where looking for. The team used a technique called gas chromatography mass spectrometry on the urine samples and found the chemical compound 2-AP which is the same compound found in popcorn that gives it its smell. The urine which is sprayed on the ground as well as on their own feet is used as a territory marker designed to ward off other bearcats competing for resources, and to attract potential mates.

Since the bearcat doesn't eat popcorn in the wild the team of scientist wanted to know how they made the 2-AP compound. They believe that there is certain bacteria in the bearcat that uses the urine as a source of nutrients. When the bacteria begin to break down the urine, they inadvertently produce 2-AP which in turn gives of the popcorn smell

Original source: http://phys.org/news/2016-04-chemical-compound-rare-animal-popcorn-like.html

Altering Mosquito's Sense of Smell

On a hot summer day, hiking through a wet area, you find yourself being a plate of food for mosquitoes. By the end of the trip, you are covered in bug bites and the all you can think about it is cursing those damn mosquitoes. In a ScienceDaily article, it was reported that researchers have developed a way to alter an insect's sense of smell. Ocro was identified to be a gene that contributed to odor sensing in mosquitoes. When this gene was silenced, mosquitoes had difficulty sensing odors. Furthermore, the study showed that mosquitoes did not hold a preference toward a certain species (including humans). However, mosquitoes were shown to land on DEET (main component in bug repellent) covered subjects, but quickly fly away. Therefore, this indicates that there are multiple mechanism involved with sensing odors. All in all, orco was shown to interfere with an insect's receptors on sensing smells. As a result, future studies will dive deeper into understanding the other mechanisms involved with certain repellents and why mosquitoes prefer humans.

The Genetically Engineered Mosquito

The sense of smell is such an important way to retrieve information from our surroundings. It only took one gene to confuse a mosquito from its normal behavior. I believe that even though there is a genetically modified version of the mosquitoes that has no preference to humans, it would not survive in the wild due to the fact that humans are the most accessible type of nutrient for mosquitoes. Mosquitoes continue to favor Human for a reason. That is why the genes for this specific affinity were passed down. It was favorable to them, and those that could better sense Human odor better, survived more easily.