Thousands of people who are frequently exposed Corona virus Have never been infected. Scientists hope DNA They can provide clues to new types of treatment. «Angelica Kaukaki»The flight attendant after this during the epidemic Virus He is not infected, he thinks about whether he has a specific DNA or not. He is probably one of those people who may be genetically resistant to the coronavirus.
Scientists are now trying to figure out how the virus works. Can this feature be used to produce new drugs against this infectious disease?
Kaukaki previously worked with people who tested positive for the Corona virus. However, he was never infected. Then in July 2021, His wife had severe coronary heart disease. Again, Kaukaki had no symptoms while taking care of his wife in an apartment for about two weeks.
His tests were still negative and it was found that no antibodies were produced in his body during this time. “Every day I heard from doctors that I might get coronary myself, but every time my test was negative,” he says.
Although both had been vaccinated, his wife was re-infected with the Amicron coronavirus. Kaukaki was isolated with him for five days and again had no symptoms. His tests were still negative. This made him suspicious of his particular genetic type.
One Online article To him «Evangelos AndriakosAn immunologist at the Biomedical Research Foundation of the Athens Academy in Greece. He is part of a research team called “COVID Human Genetic EffortIs looking for genetic changes that may indicate why some people never get the Corona virus.
Although Andriakos and his colleagues did not expect to find such people in large numbers, they came across emails from at least 5,000 people around the world with stories similar to Kaukaki. Andriakos and his team used saliva samples from 20% of those who met their study criteria to examine the volunteers’ DNA to determine their genetic sequence. “We expected a small population to have this feature,” says Andriakos. “But the story seems to be more complex than we thought.”
Resistance to other viral infections
«Johann Nordgern“Molecular virologist from the university”Linkshopping“Before, we only focused on pathogens,” says Sweden. “But now we have to look at the genes as hosts and whether the genes have the ability to fight the virus.”
However, in the last two decades or so, scientists have been studying the relationship between relationships. They do this by comparing the genetic sequences of people infected with the virus with those of healthy people, looking for the link between mutations and resistance.
In 1996, this method enabled molecular biologist Stephen O’Brien and colleagues to discover a rare genetic mutation that protects against the human immunodeficiency virus that causes AIDS.
Most humans have a protein receptor in their body that is mainly on the surface of certain immune cells calledChemokine receptor 5” Or “CCR5” There is. This receptor allows HIV to attach to and enter the cell. But O’Brien’s team discovered that some people have mutations in the body that produce a defective receptor.
For resistance, a person is given two copies of this mutation that mutation «Delta -32Is called, needs – in other words, each mutation must have been inherited from each parent. A single copy in the body can allow the virus to infect cells.
“Delta-32 was a good example of convincing people why genetics are important and that there is a possibility of genetic resistance in the body,” says O’Brien.
Scientists have also tracked a mutation in a different gene that resists specific types of neuroviruses that are a major cause of acute gastroenteritis worldwide. This mutation prevents the neurovirus from entering the epithelial cells of the human gastrointestinal tract.
«Lisa Lindsmith“Neurovirus researcher at the university”North Carolina” At “Chapel Hill“In other words, the body creates a port through which the virus can enter the body or not,” he says. If this input port does not exist, it does not matter how much virus enters your body. “Eventually you will not get sick.”
While genetic resistance to viral infections such as coronavirus is not widespread, the fact that it exists even slightly increases the interest in studying genetic mutations, especially against coronavirus.
Coronavirus-resistant genetic support
Following the corona epidemic, researchers sought to establish a link between resistant genetic underpinnings and the virus. In these studies, they not only relied on medical staff, but also collected information from people like Kaukaki.
Scientists have hypothesized that if these people are repeatedly exposed to danger and continue to survive, they are more likely to have a mutation that is resistant to the virus.
One of the important points in this study is the study of the gene that the recipient «ACE2The human and the receptor define cell level regulators as code. Virus « SARS-CoV-2 It must bind to ACE2 to enter cells and infect the body. In people with a mutated genetic structure, the virus is prevented from binding and causing infection.
«Jean Laurent Casanova“University geneticist”Rockefeller“ACE2 seems to be the best option to study until we get the answer,” he said. “Genetic alterations that allow ACE2 to function normally in the body but reduce its interaction with the virus are good candidates for our studies.”
However, there may be other biological factors besides the ACE2 receptor that may explain why some people do not have coronavirus infection.
Some people may have a very strong immune system that produces antiviral proteins called interferon I, which restrict the virus from multiplying in human cells. They are the body’s first line of defense and show up even before antibodies are formed against the virus.
Another hypothesis is that immune cells calledT cellsDuring human infection, coronavirus-like viruses – such as colds and flu – are produced in the body that increase resistance to the corona.
In 2020, before the vaccine was introduced, a study showed that the number of T cells in the body of doctors and nurses who were exposed to the virus but were not.
T cells may be the cure for several types of infections, but there is no guarantee that these people will be safe from other types of infections or severe coronary infections. «Mala Maini“Viral immunologist from the university”College of London“In fact, we know that some of them have contracted the disease at a higher dose of the virus,” said one study author.
If the studies provide clues to genetic resistance, Casanova hopes the information could be used to develop treatment for coronavirus, as it was for HIV. The decision to develop these therapies depends on the nature of the mutated genes discovered, Casanova said.