Provided by Perimental Dermatology
In June 2023, the cover of “Experimental Dermatology”, an international academic journal in the field of dermatology, featured an image that looked like layers of colored clay. The identity of the image is the “cuticle”, the outer covering of the hair. The cuticle image was actually taken and colored layer by layer using a design tool. After finding out which part of the cuticle it was, I had no choice but to contact the research team. It was a conspiracy.
The topic of the article, which also appeared on the cover of an international academic journal, is “Why is pubic hair curlier than hair?” (doi: 10.1111/exd.14855) When we looked at who was responsible for the research that is likely to receive the “Ig Nobel Prize” in the near future, it was a team of domestic researchers, Professor Shin Kwan-woo from the Department of Chemistry of Sogang University.
On November 3, I visited science communicator Lee Min-hwan, who runs the science YouTube channel “Intellectual Minani,” and his lab to ask him how he started his research.
“It’s out of curiosity.” Professor Shin replied with an embarrassed smile.
Professor Shin first published a paper studying the protein structure of hair in 2016. At that time, through research, he discovered that hair does not dissolve in strong acids. In fact, in the case of patients suffering from trichotillomania who habitually eat their own body hair, the tufts of hair accumulate in the stomach and often require surgery. This is because the cuticles surrounding the fur are resistant to acids.
Professor Shin proposed a new research topic: whether it would be possible to develop an acid-resistant coating technology by exploiting these characteristics of the cuticle. The study also hypothesized that thicker, stiffer pubic hair would be more resistant to acidic solutions. This is how the somewhat awkward search began.
A scene from the video “Introduction to Fur Research”. Capture the intellectual Minani from YouTube
● Conspiracy science with great interest but little research
Many people are already wondering why pubic hair is curlier than other hair. Places on the Internet and foreign magazines suggest various reasons why pubic hair may be frizzy. Some claim that curly hair acts as a cushion to reduce friction during sexual intercourse, while others say that curly hair is beneficial in spreading pheromones secreted around the genitals.
There is also a hypothesis that curly pubic hair proves that humans diverged from ancestors like gorillas. Comparing the fur of a gorilla and that of a chimpanzee, the fur of the gorilla is coarser and curlier than that of the chimpanzee. This is similar to human conspiracy.
On the other hand, chimpanzee fur is similar to human hair. In other words, in terms of fur, chimpanzees evolved further from gorillas and humans evolved from chimpanzees until they lost their fur.
In fact, among the parasites that live in human hair and pubic hair, “pubic lice”, a parasite that lives in pubic hair, exist only in gorillas. Furthermore, “lice” parasites in hair only exist in chimpanzees. Therefore, only in terms of DNA similarity, humans are more similar to chimpanzees, but based on the shape of pubic hair and parasitic pubic lice, it can be assumed that they may also be closely related to gorillas.
Professor Shin said: “This is the only way to scientifically address conspiracies,” and added: “I realized that there was no study that scientifically verified this information, which everyone is curious about, so I decided to conduct the research myself.”
Hair (left) and pubic hair (right) used in a comparative experiment by Professor Shin Kwan-woo of the Department of Chemistry at Sogang University. Provided by Shin Gwan-woo
● Which texture was used in the experiment?
Professor Shin led the reporter to the Bio-Imaging Center on the second floor of Building K of Sogang University. This was a place to create image materials needed for research. Among the cutting-edge imaging equipment, the first thing that caught my attention was the “conspiracy” used in the experiment. I asked hesitantly. “Whose hair is this? (Could it be the research team’s hair?)”
Professor Shin, who was asked a question, smiled broadly and explained the process of obtaining the materials, saying, “Surprisingly, many people are curious about it.” In general, for human experiments used in research, ethical guidelines must be followed. Therefore, most schools have a bioethics committee, and materials for human testing can be obtained with the committee’s approval.
In particular, it was underlined(?) that the human hair of the research group was never used in the research because it was contrary to the guidelines. After receiving the committee’s approval to compare hair and pubic hair, Professor Shin asked acquaintances in their 20s, 30s and 40s for help. “There were more people curious about their hair than I thought, so it was easy to get it,” he recalled.
Transverse hair analysis. Provided by Scienza Donga
● After comparison under the microscope and immersion in acidic and basic solutions,
The method of comparative study of hair and pubic hair was quite intuitive. First, take a close look at each hair. The equipment used at this time is a low-voltage scanning electron microscope (SEM). The low-voltage SEM magnifies thin areas of materials that are difficult to observe with a general optical microscope at high resolution and magnification, minimizing damage. The research team used low-voltage SEM to check the cuticle layer and cross-section of hair and pubic hair.
The cuticle is formed by hardening the keratinocytes cells that produce keratin, the protein that makes up hair, and continues to grow, covering the side where new hair grows. It’s easy to understand if you think about the “bamboo shoot”, which is the new bamboo shoot. The skin of the bamboo shoots grows with the skin of the last growth layered on top of each other. The cuticles also become thicker, like bamboo shoots, with new cuticles covering the old ones.
The results of the study showed that pubic hair had much more numerous and thicker cuticles than hair. The cross-sectional view also showed that the hairs were thin and almost circular, while the pubic hair was thick and almost oval in shape. Professor Shin explained: “In the case of pubic hair, the more cuticles accumulate, and the more they accumulate, the thicker a specific part can become.” a shape closer to an oval than a circle. If the cuticle on one side is thicker and the cuticle on the other side is thin, the hair will naturally bend and look curlier.
The difference in shape between pubic hair and hair depends on differences in the hair follicles that produce the hair. Professor Shin said: “The presence of multiple cuticle layers means that hair follicles produce more cells and protect them from the outside,” adding: “Compared to hair, pubic hair is more easily exposed to environments such as urine , so the cuticle layer might have been thicker.” He reasoned.
Professor Shin developed the hypothesis that “pubic hair cuticles would grow to protect the hair from environments such as urine” and conducted a real test experiment. To compare the extent to which hair and pubic hair are damaged in a urine-like environment, hair and pubic hair were placed in extreme acidic and basic solutions and observed using an infrared spectroscopic microscope (FT-IR).
FT-IR is a device that can visually monitor chemical changes in hair. Using this equipment it is possible to observe which chemical reactions occur when hair and pubic hair are immersed in various solutions with different concentrations of hydrogen ions (pH).
The results of the observations showed that pubic hair had greater resistance than hair when exposed to acidic solutions such as urine. Ultimately, Professor Shin argues that pubic hair has become thicker and stronger to withstand the extreme (?) environment around it.
Is curly hair more resistant to the cold? Provided by Getty Image Bank and Science Donga
The curlier the animal’s fur, the warmer it is. Provided by Getty Image Bank and Science Donga
● Pure curiosity rather than grandiose goals
The study of conspiracies was simply a study to satisfy curiosity. However, that doesn’t mean it has no real-life use. This is because coating materials can be developed using the characteristics of the cuticle. Professor Shin said: “Cuticles may be the strongest acidic coating material provided by the natural world. If we use cuticles to create an ‘edible coating’ on meat or artificial food, we will be able to better preserve the food without spoiling it “. I expected that. Professor Shin, in fact, is analyzing different animal furs, including not only pubic hair but also wool, to develop this coating technology.
At the end of the interesting talk, Professor Shin revealed the story behind the publication of the article. In fact, it took a long time for this conspiracy document to be released to the world. Even though I researched diligently for 1 year and 6 months and submitted the article to a journal, I received several requests for revision as it was deemed “without academic significance.” Professor Shin said: “If I had highlighted the usefulness and research methods of this study in the article’s abstract, I would not have received so many requests for review,” adding: “But I didn’t want to do that.”
Hair soaked in an acidic or basic solution composed of HCl and NaOH. From the left, the hydrogen ion concentration (pH) is 1.10, 3.00, 5.06, 7.09, 9.06, and 12.03. The hair maintained its original appearance without melting even after 45 days at all concentrations. This means it is resistant to both acids and bases. Provided by Shin Gwan-woo
“I don’t think every experiment has to have some grand purpose. If simple curiosity can be solved scientifically, it becomes a purpose in itself. “It’s important to have big, lofty goals like developing new drugs, designing semiconductors, and developing space propellants, but I didn’t want to change the fact that the purpose of this research was pure curiosity.”
Professor Shin, who emphasized the pure curiosity of a scientist, said he had something he wanted to convey to Science Donga readers who dream of becoming scientists.
“It’s easy to see that even scientists who have done great research say it was out of simple curiosity when asked, ‘Why did you become a scientist?’ “It may seem small and insignificant, but I think the true meaning of basic science is to allow people to conduct research simply out of genuine curiosity.”
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2023-12-30 23:00:00
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