Genetics plays an enormous role in our lives, even if we don’t always realize it. Have you ever wondered why some people love cilantro, but it tastes like soap to others? While it might all be in your head, chances are it’s actually in your genes.
A study was posted to arxiv.org in 2012 that surveyed the genetics of more than 30,000 individuals and was one of the first that suggested that the dislike of cilantro could be genetic. This study indicated that there are two genetic variants that could cause cilantro to smell like soap instead of taco toppings.
Cilantro isn’t the only thing that might smell a little weird to some people — genes also affect how people perceive the tastes of things like PTC, powdered phenylthiocarbamide, an inherently bitter substance — as well as milk and sweet or sugary foods. However, because of the sheer number of subjects that it takes to find just one specific gene related to taste, it can be hard to consolidate enough genetic candidates for individual labs. That’s where citizen science comes in.
The Genetics of Taste
Crowdsourcing isn’t just limited to fundraising. Rather than restricting their pool of genetic candidates to one lab or one demographic area, researchers are able to source information volunteered by thousands of individuals from around the globe. This data is then analyzed by citizen scientists, giving the researchers a broader spectrum of genetic data to work with.
Researchers at The Genetics of Taste Lab, part of the Denver Museum of Nature & Science, have taken it upon themselves to figure out how our genes affect our sense of taste. Dr. Nicole Garneau, Curator and Department Chair of the Denver Museum of Nature & Science, said this lab builds on the museum’s mission to “ignite our community’s passion for nature and science” and to “co-create experiences for and with our communities.”
The lab itself is part-research lab, part-interactive exhibit. The Genetics of Taste Lab is open from November to August every year, only closing on December 25th for Christmas. Visitors can participate in taste studies as part of the lab’s research, enabling the lab to gather data from volunteers who are visiting the museum.
The exhibit opened in 2009 with the goal of collecting taste and DNA data from thousands of visitors to the museum. One thing that the exhibit teaches is that the traditional ‘taste map’ that shows the different parts of the tongue and what flavors they taste is, well, wrong. You’ve probably seen the one — it says you only taste sweet with the tip of your tongue and bitter flavors with the back. Turns out: it doesn’t work that way. All of your taste buds can absorb and process any number of flavors. Each taste bud is capable of discerning the five primary flavors — sweet, salty, sour, bitter, and savory.
The first project, which ran from 2009 to 2013, challenged volunteers to identify how well they could identify bitter flavors. Researchers confirmed that a person’s ability to discern bitter flavors was dependent on the presence of one gene, dubbed TAS2R38, which was discovered in 2003. Due to variations in that gene, the bitter flavors might taste different to someone without the gene than to someone with the gene — or a person might not taste anything at all.
In another study, the team explored whether people taste fat the same way they taste bitter, savory, salty, or sweet flavors. The researchers originally postulated that overweight or obese individuals would grow less sensitive to the flavor of fat, enabling them to eat more of it and further contributing to their obesity. They found that is not the case: in their Fatty Acid Taste Study, they determined that while humans are capable of tasting fat, or oleic acid, taste sensitivity does not, in fact, decrease in those who are overweight or have obesity.
Most recently, researchers opened a “Sweet Tasting” study that invites participation from anyone ages eight and up. The newest project, which is still collecting data, studies how intensely people taste sweet flavors. In addition to the flavor profiles, the researchers plan on profiling the kinds of bacteria present in volunteers’ mouths while they taste these sweet things.
The Importance of Citizen Scientists
The community can also participate through the project’s community science program, which allows visitors to contribute to the scientific process and learn more about how genetics works.
This is the essence of citizen scientists. Volunteers, even those under the age of 18 who can’t yet participate, spend their time assisting until they reach their 18th birthday.
How is this museum able to create such engaging studies? Dr. Garneau further explained that the National Institute of Health awarded them a $1M Science Education Partnership. She said, “[it] is allowing us to not only do more in bringing genetics research to the community, but also [allows us] to understand who participates in community science and why.”
There are still many, many things we don’t know about genetics and how our genes affect us in the real world. As Garneau explains, “[G]enetics to most people is a big black box, and one that is associated with quick news clips dealing with diseases. It’s an incomplete story that generates fear rather than celebrating that genetics is part of everything that makes us who we are every day, not just when we’re sick.”
Just one sequenced genome takes up more than 200 gigabytes of storage space. Citizen scientists are a great solution to help researchers make a breakthrough. These are the armchair scientists — people who love science and are happy to help but might not have received formal training or a science degree. By learning why certain people in the community participate, these scientists can continue to create engaging studies that help us learn more about the world around us.
“For centuries, museums have inadvertently shown modern humans as separate from nature. The Denver Museum of Nature & Science teaches that people are not just in nature, but part of nature. By studying modern humans alongside other mammals, insects and dinosaurs, we are showing our communities that we are all part of and therefore responsible for the health of ourselves, the earth, and all its inhabitants,” said Garneau.
Museum visitors who would like to donate their time, data, and DNA to study taste simply complete an enrollment form at the museum, then answer a few questions about their ability to taste, complete a guided taste test, and complete a cheek swab for DNA analysis.