Do genes affect spice tolerance?

    Have you ever wondered why some people seem to relish the burn of spicy foods while others shy away from anything hotter than a bell pepper? The answer may lie in our genes, according to recent research articles. Let's delve into the fascinating world of taste preferences and the genetic factors that influence them.

    In a study titled "Why do some like it hot? Genetic and environmental contributions to the pleasantness of oral pungency," by the National Library of Medicine researchers explored the pleasantness of oral pungency, particularly in response to spicy foods. This study, involving young adult Finnish twins, revealed intriguing insights into how genetics and environmental factors shape individuals' responses to spicy sensations. It indicated that genetic factors accounted for a significant portion of the variation in the pleasantness of oral pungency and spicy foods. Individuals were categorized into non-likers, medium-likers, and likers based on their responses, highlighting the diverse nature of taste preferences influenced by genetic predispositions.

    Additionally, according to a study titled "The Health Risks of Eating Extremely Spicy Foods," conducted by urgent care provider Allan Capin, MD, the allure of spicy foods is not merely a matter of personal preference; it's deeply rooted in genetics. Capsaicin, the fiery compound responsible for the heat in peppers, triggers heat receptors in the skin and tricks the nervous system into reacting as if the body is overheating. This sensation, akin to putting your hand over a flame, varies in intensity depending on individual tolerance levels and genetic predispositions.

    

    These findings offer valuable insights into the diverse nature of individual food preferences and the underlying genetic components of oral pungency. Understanding the genetic basis of taste preferences can pave the way for personalized dietary recommendations and the development of tailored food products that cater to varying taste preferences.

    For consumers, this research sheds light on why some people are drawn to spicy foods while others find them intolerable. It underscores the importance of considering genetic factors in understanding and accommodating individual taste preferences. Moreover, for food manufacturers, this knowledge can inform product development strategies, allowing them to cater to a broader range of consumer palates.

    The study on the genetics of taste preferences adds another layer to our understanding of human food behavior. By unraveling the spicy mystery, researchers offer insights that could revolutionize how we approach food consumption and product development in the future. Whether you're a spice aficionado or prefer milder flavors, there's no denying the role that genetics play in shaping our culinary experiences.

Sources:

https://health.clevelandclinic.org/health-risks-of-spicy-food

https://pubmed.ncbi.nlm.nih.gov/23010089/

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. 

How octopuses ‘taste’ things by touching

 

In this article from Science news, researchers have identified unique nerve cells in octopuses that allow them to taste with their arms. The cells detect the chemicals that are produced by many aquatic creatures and help the octopus distinguish rocks, food and even poisonous prey. All this research was done by a molecular biologist named Nicholas Bellono and hiss colleagues at Harvard University. 

The researchers also speculated that these new findings help look at the bigger picture regarding the evolutionary path of octopuses. The found that tow thirds of nerve cells are scattered throughout the octopuses arms which allows them to operate semi-independently. To learn more, Bellono and his colleagues looked at the arms of a California two-spot octopus and saw what appeared to be sensory cells with fine branched endings. These cells were then isolated to test how they respond and they turned out to be very similar to those that detect touch. The researched did another study to see how the receptors worked and inserted them into human and frog cells. They also confirmed that octopuses do use receptors to sense chemicals by touch and the researchers are already working on trying to identify other compounds that could be detected by these sensors.

I think that this is a great evolutionary find. Who knows what else octopuses can do that we are not aware of. Its crazy to think they these creatures use their arms for touch and for taste. I hope more studies are done to find out more information. I have attached another article that looks into the mind of an octopus. 

Links:

https://www.sciencenews.org/article/octopus-taste-touch-arm-suckers

https://www.scientificamerican.com/article/the-mind-of-an-octopus/

How Do Genetics Affect Taste?

Scientists have identified a gene, TAS2R38, which plays a role in how we taste food. The presence of the PAV variation of this gene causes certain foods to taste bitter. in a study of 175 people, those with the PAV variant were 2.5X as likely to report that they do not eat many vegetables. In the future, this could be used to identify the flavor preferences of individuals and help create a more nutritious diet. This gene was already utilized to predict sweet food preferences in young children.



I do not believe that your sense of taste is determined by a single gene. I am not convinced that it is fully genetic either. While you may have a genetic predisposition to a flavor, your taste is shaped by what you are exposed to. For example, many people think that their mother's cooking is better than any other that they've had. Scientists are currently unable to explain how tastes change with age when there is no genetic differences within your tastebuds. While this is an interesting discovery, it is only a piece of a bigger story.

Links:
http://www.sci-news.com/genetics/genetic-food-choices-07813.html
https://www.smithsonianmag.com/arts-culture/the-genetics-of-taste-88797110/

Coffee or tea? Your preference may be written in your DNA

Complete articles are here: Link 1 & Link 2

Individuals with a form of a quality that builds affectability to the harsh kind of caffeine will in general be espresso consumers, analysts report online November 15 in Scientific Reports. Tea consumers would in general be less delicate to caffeine's harsh taste, however have variants of qualities that expansion affectability to the harshness of different synthetic substances, the scientists found.

It's for quite some time been believed that individuals abstain from eating harsh sustenances since harshness is a pointer of toxic substance, says John Hayes, a taste scientist at Penn State who was not engaged with the investigation. The espresso and tea discoveries help test that "excessively oversimplified 'severe is in every case terrible, how about we keep away from it'" see, he says.



In the new examination, specialists analyzed DNA variations of qualities engaged with identifying the unpleasant taste of the synthetic concoctions, caffeine, quinine — that severe preference for tonic water — and propylthiouracil (PROP), an engineered compound not normally found in sustenance or drink. Other severe segments normally in espresso and tea may trigger a similar taste reactions as quinine and PROP do, Hayes says.

Specialists in Australia, the United States and England analyzed DNA from in excess of 400,000 members in the UK Biobank, an archive of hereditary information for restorative research. Members additionally announced other data about their wellbeing and way of life, including how much tea or espresso they drink every day.

The group included every individual's variations in the taste qualities, making a hereditary score for how seriously the individual tastes every one of the severe synthetics. The scientists at that point contrasted those scores with the general population's accounted for drink decisions.

Sweet Tooth? Now it's Salt Tooth?

Everyone knows about the sweet tooth, but do you have a salt tooth?

Studies have found a gene, TAS2R48, that codes for a taste for salt, but no need to be salty about it (sorry for the pun, saw an opportunity and I took it), it's just that you would prefer saltier foods than any other, which is useful information for the American Heart Association.

We all know that the AHA recommends a limited amount of sodium in our diet, but people that express a preference for salt, are going to have a much more difficult time cutting down on the salt.  These people, because of TAS2R48 are at much higher risk of high blood pressure. Those in the study that had the gene were found to exceed the daily limit of sodium recommended by the AHA, 2,300mg. In previous study, researches suggested that the people that had the variation of gene for salt preference also enhanced their bitter tastes. "There is some research suggesting that individuals who taste bitter more intensely may also taste salt more intensely and enjoy it more, leading to increased sodium intake," Jennifer Smith, a Phd nursing student at the University of Kentucky College of Nursing, said in a statement.

So if you have the salt gene, TAS2R48, be mindful of sprinkling more salt on your vegetables and cut down on the ramen!

Androstenone Levels and the Taste of Pork

Several months ago, Science Codex published an article that highlighted a study relating the taste of pork to genes associated with scent.  The study was a collaboration between Hiroaki Matsunami of Duke University and scientists in Norway.  The Norwegians were interested in working with Matsunami because in a previous study he discovered the OR7D4 gene which codes for an odor receptor for androstenone.  Androstenone is a compound commonly found in the urine of swine (pigs).  Currently, the pork that is sold in Europe comes from female or castrated male swine.



The Norwegians wanted to see if consumers would be able to detect androstenone from noncastrated swine.  The scientists were interested in studying this because the European Union will be banning piglet castration by the year 2018 in all European countries.  It was found that noncastrated pigs contained a 6.4 ppm level of androstenone while castrated pigs contained only a 0.1 to 0.2 ppm level of androstenone.  The study used 23 participants, 13 who were consumers and 10 who were professionals.  Each participant was divided into a group based on whether they could or could not detect androstenone.  According to an article in Time, each person detects androstenone in different ways.  It can be perceived as having a scent ranging from urine to the sweetness of vanilla.  The participants who detected androstenone had two functioning copies of the OR7D4 gene.  Those who could not detect androstenone contained only one functioning copy of OR7D4 or none at all.  The important finding was that 70% of the participants had two functioning copies of the OR7D4 gene and thus were sensitive to androstenone.

This study shows that the upcoming ban in 2018 may negatively impact many people living in Norway.  More studies should be completed to see if the proportion of people impacted in Norway correlates with the rest of the population in Europe.  If 70% of all Europeans have two of the OR7D4 genes, meat producers may have to alter some of their practices.  Pork from females or imported pork from castrated swine may become prevalent in European grocery stores.  The study as a whole illustrates the importance of genetics and how a single gene can alter one’s perception of the world.  Further studies should be completed to see if other genes affect taste or scent.