A Reddit post made a big splash on the internet this week when it was claimed that the infamous $ 30 "GamerGirl bathwater" sold by the social media star Belle Delphine did not contain any human DNA – and therefore cannot be her bathing water at all . This was immediately challenged by other Reddit users and debunked: the shipments of said bathing water had not even been sent out yet. When the news of the non-scandal broke about The Verge offices, the reporters began paving the science table with questions, including; "Wait, you can test the bathing water for DNA?"
"Yes, you can," says forensic biologist Helen Page. Page is a senior lecturer at Teesside University in the UK and has actually studied how to restore highly specific samples of DNA from a bath.
That's serious work. Recycling DNA from a shower or bath can be useful in the investigation of sexual abuse, especially if a victim does not want to undergo a complete forensic examination or is slowed down after the assault. The site has studied how sperm can be recovered from specially designed mesh objects that are designed to fit into the shower drain, and "bath tips" (also known as sponges, loofahs or puffs). She found that you can recover DNA from nets, from scrunchies, and also by simply wiping around the walls, bottom and drain of a bathtub.
The page has shown that it is possible to recover DNA from sperm in bathing water, but the semen is very different from other cells. "The structure of the sperm is quite resistant, even for degradation in the same way that other cells would be," Sid says. In the case of Delphine, the most likely source of DNA would be skin that may become slug in the tub. The site survey was also conducted under controlled conditions in the laboratory. When it comes to "GamerGirl Bathwater", without seeing the manufacturing process, it's really no way to know how much of Delphine's DNA is in the water.
"It's hard to know how many cells would have been lost in the washing process," Sid says. She points out that if Delphine was washed easily, fewer skin cells would come out than if she washed more carefully. "I doubt very much that there will be a large amount of DNA in a small bottle of bathing water," says the page.
It is not clear how long DNA would also be in bathing water. The greatest threats to DNA's integrity are heat, humidity and bacteria, which the tubes have in abundance. Soap and other cleaning products can also play a role in breaking down DNA, but there is not enough scientific research available to know for sure.
Although there is enough DNA in the water to test and you had the right laboratory equipment and it has not "broken down, all the analyzes can say that a person is whether the DNA is human, not which person bathed in it. "You wouldn't be able to say that it was her DNA if you didn't have her DNA profile to compare against." The page says.
Of course, this is only about the question of whether people could – not whether they should – test a small jar of $ 30 bathing water for DNA in the first place. Why it is sold is crystal clear: As Patricia Hernandez points out at Polygon, Delphine is known for performance stunts.
While Sid emphasizes she would not spend her money on bath water, she understands why people might want to verify their purchase. "If I paid so much money for a little water that had been bathed by Person X," says the side, "then I want the bath water to be bathed by P erson X ".