Wednesday 21 April 2021
Genetic implications in East Asia
Corona epidemic 25,000 years ago?
The uniqueness of a corona pandemic is mentioned repeatedly. But research now indicates that this is not the first time that humanity has been afflicted with the Coronavirus to a large extent.
There could be a prolonged coronavirus epidemic in East Asia 25,000 years ago. This is the conclusion scientists from the Australian National University reached. Them as early as January Published a preprint study Yasin Soilmi and colleagues analyzed the genetic makeup of 2,500 fine individuals from 26 different populations around the world. Several groups of East Asians about 900 generations ago were prominent.
When comparing the data, scientists specifically looked for genes that provide evidence that people have actually encountered the Coronavirus. “In the context of the evolutionary history of our species,” the researchers write, “natural selection has often favored proteins that interact with viruses – for example because they improve immune protection or that viruses need to fit into a cell mechanism.” 420 of these VIP-interacting proteins are known as coronaviruses alone.
In the case of epidemics, it is preferable to be transmitted because it brings survival benefits. Therefore, the occurrence of these genes illustrates whether and when a group of people has been subjected to selection pressure from coronaviruses. In East Asian populations, the researchers found a “strong fertilization signal” from the virus-interacting proteins. In contrast, this genetic signal was absent in populations from other regions.
A sudden and sustained increase
According to scientists, the genetic variants that are increasingly occurring in East Asia are specific to proteins associated with the Coronavirus. On the other hand, the proteins that interact with other viruses were not significantly altered. This speaks of a more severe and longer-lasting coronavirus epidemic in the past.
To more accurately determine the history of this epidemic, 42 senior figures were examined in more detail. Scientists found that the number of mutations in the genome of former East Asian residents suddenly increased significantly. “The pattern matches an epidemic that led to a strong increase in the selection of such virus-interacting proteins 25,000 years ago,” the researchers explain. In their opinion, the Coronavirus epidemic may have persisted into the Stone Age for several generations because that was the only way to explain the apparent and persistent rash. After that, the epidemic has calmed down again – perhaps because the population has largely become immune. For about 200 generations, no genetic variants associated with the Coronavirus have been added in East Asia.
The researchers concluded from their results that corona viruses spread to humans for thousands of years and caused larger epidemics. They do not consider it a coincidence that the Stone Age epidemic hit East Asia in particular. Because to this day, this region of the world is the main distribution area for potentially zoonotic coronaviruses.