by The viruses that we know best are those who make us sick – the flu viruses that send us to bed and the smallpox viruses that can send us to the grave.
But healthy people are full of viruses that don’t make us sick. Scientists estimate that dozens of trillions of viruses in our lives, although they have only identified a fraction of them. A vast majority is benign and some can even be useful. We don’t know for sure, because most so -called human virome remains a mystery.
This year, five universities are working together for an unprecedented yacht to identify these viruses. They will collect saliva, stools, blood, milk and other samples of thousands of volunteers. The five-year effort, called the human virome program and supported by $ 171 million in federal financing, will inspect the samples with artificial intelligence systems, hoping to learn how human virome influences our health.
“I think it will flood the data that we have had so far,” said Frederic Bushman, a microbiologist at the University of Pennsylvania and one of the leaders of the program.
The first hints of the human virome rose more than a century ago. Scientists analyzed relief samples and discovered viruses that are known as fagers who could infect bacteria in the intestine. Fagen also stood up in the mouth, lungs and skin.
Scientists later found viruses that infected our own cells without causing important symptoms. A large majority of the world’s population, for example, is infected with cytomegaloviruses, which can, for example, colonize just about every organ.
In the early 2000s, new genetic sequence methods led scientists to find even more viruses in saliva, blood and stools. The technology also enabled them to estimate the number of viruses in our body by counting copies of viral genes. Every gram of stools, pale, contains billions of phages.
The intestine of each person can accommodate hundreds or even a thousand types of phaags. But when biologists go from person to person, they will find many viral species in one that is lacking in another – even when those people are married. The more people study scientists, the more phagees they discover.
“I expect tens of millions of species,” said Evelien Adriaenssens, a paagbiologist at the Quadram Institute in Norwich, England.
The viruses that infect human cells have proven unexpectedly diverse. In 1997, researchers in Japan discovered a completely new virus family that became known as anelloviruses. Last month, a study unveiled more than 800 new types of anelloviruses, which brought the total number of known species more than 6,800.
Some recent studies on the human virome call questions about the definition of a virus. A standard virus consists of a protein scale that holds genes that are encrypted in double -stranded DNA or single -strand RNA. But scientists believe that our body is also home to beautiful small rings of fairly floating RNA.
Scientists are still blind to many of the human virome. Viruses are so small that they can lurk in cells. Some can even sneak their genes in the DNA of their host cell, where they can hide for years before they replicate.
“Totally new tools will have to come in,” says Dr. Pardis Sabeti, a computational biologist at the Harvard Th Chan School of Public Health.
Dr. Sabeti and her colleagues are developing an artificial intelligence system that will implement the Human Virome program to discover subtle characteristics of viral genes.
The researchers will then try to find out what all those viruses do in our body. Scientists have traditionally treated phages, such as predators of bacteria, ruthless killing to make more copies of themselves. But recent experiments indicate a much more complicated relationship.
“They are not contrary to death,” says Colin Hill, a microbiologist at APC Microbiome Ireland, a research center in Cork. “They are in a partnership.”
In the human body, for example, rats usually do not rather their host bacteria. And bacteria can take advantage of their friendly relationships with phages, which can move genes from one hostheermicrobe to another, which may stimulate their survival.
This collaboration can also be good for our health. Recent studies suggest that Fagen Defensive Genes distribute that their hosts can use to stop the incoming pathogens. And cytomegaloviruses can help us defend against skin cancer.
Dr. Shadmehr Demehri, an immunologist from Harvard Cancer, and his colleagues have found evidence that cytomegaloviruses become active in skin cells damaged by the sun. The infected cells make viral proteins, which attract the attention of nearby immune cells. They attack the damaged cells – and can therefore prevent them from continuing to cancer.
Dr. Demehri’s studies have shown that human papillomaviruses can also help destroy skin cells that run the risk of producing a tumor.
“It is a paradigm shift in how we think of viruses in general,” said Dr. Demehri.
