Researchers have made a groundbreaking discovery in Siberia. They found a piece of woolly mammoth skin with well-preserved fossil chromosomes. This find is truly unique and the first of its kind.
In 2018, researchers unearthed the 52,000-year-old mammoth remains near the village of Belaya Gora in northeastern Siberia. The cold weather helped keep the chromosomes, which carry genetic material, intact.
Unlike past discoveries of ancient DNA, which often have tiny, fragmented pieces of genetic code, these chromosomes are practically whole. They provide a much clearer picture of the woolly mammoth’s genetic information, as reported by CNN.
Erez Lieberman Aiden, a professor at Baylor College of Medicine, highlighted the significance of the find, stating, “Fossil chromosomes have never been found before.”
The researchers call these chromosomes “non-mineralized fossils, or subfossils.” They are well-preserved enough to allow scientists to piece together the entire genetic material of the extinct mammoth.
Olga Dudchenko, an assistant professor at Baylor College of Medicine and co-first author of the study, confirmed this level of preservation.
Freezing temperatures slow down DNA structure degradation
Kevin Campbell, a professor at the University of Manitoba, explained that DNA in different cell types forms unique 3D structures. These structures provide insights into the traits of that cell type. Campbell, who was not involved in the study, noted that, after death, cells degrade quickly, causing this 3D structure to disappear within days.
DISCLOSING THE 3D GENOME OF A WOOLLY MAMMOTH THAT IS 52,000 YEARS OLD
Using cutting-edge methods, researchers examined a 52,000-year-old woolly mammoth skin sample in 2018 to determine its three-dimensional genomic structure.
The finding, which was published in Cell,… pic.twitter.com/ZDfoMi8pVn
— DailyNoah.com (@DailyNoahNews) July 12, 2024
In Arctic animals like the woolly mammoth, freezing temperatures slow down this degradation. However, over long periods, the DNA still gets damaged and loses the structure and characteristics that define the species’ biology.
Kevin Campbell highlighted that this study is the first to show that DNA degradation after death doesn’t always lead to a loss of structure.
He also mentioned that DNA typically breaks into shorter pieces and loses its organization after an animal dies. However, in this study, the DNA maintained its structure, which is unusual.
DNA diffusion process is similar to making beef jerky
The loss of DNA structure after death, known as diffusion, is a process familiar to food scientists. Preventing this loss is similar to the techniques used in making beef jerky, according to Dudchenko.
“Arresting diffusion is key to preserving foods, so if you want to have something that is shelf stable for a long time, you basically need a combination of dehydration and cooling,” she said. “Any shelf stable food that’s not canned is probably in a state of arrest of diffusion.”
Dudchenko suggested that when the mammoth died, the conditions might have naturally begun the preservation process.
She also said that the carcass could have spontaneously undergone a similar process to modern commercial preservation methods, which involve removing water and halting diffusion. Consequently, this process locked the chromosomes in place, allowing researchers to study them 52,000 years later.
