“The viruses we know best are the ones that make us sick — the influenza viruses that send us to bed and the smallpox viruses that may send us to the grave,” reports the New York Times:
But healthy people are rife with viruses that don’t make us ill. Scientists estimate that tens of trillions of viruses live inside of us, though they’ve identified just a fraction of them. A vast majority are benign, and some may even be beneficial. We don’t know for sure, because most of the so-called human virome remains a mystery.
Five universities are teaming up for an unprecedented hunt to identify these viruses. They will gather saliva, stool, blood, milk and other samples from thousands of volunteers. The five-year effort, called the Human Virome Program, will inspect the samples with artificial intelligence systems, hoping to learn about how the human virome influences our health…
The first hints of the human virome emerged over a century ago. Analyzing stool samples, scientists discovered viruses known as phages that could infect bacteria inside the gut. Phages also turned up in the mouth, lungs and skin.
Scientists later found viruses that infected our own cells without causing any major symptoms. A vast majority of the world’s population gets infected with cytomegaloviruses, for example, which can colonize just about every organ.
In the early 2000s, new genetic sequencing methods led scientists to find yet more viruses in saliva, blood and stool…Each gram of stool, it turned out, contains billions of phages.
Each person’s gut may harbor hundreds or even a thousand species of phages. But when biologists go from person to person, they will find many viral species in one that are missing from another — even when those people are married.
Viruses can be useful. Scientists have engineered a virus to steal proteins from the HIV virus, potentially eliminating AIDS.
A virus is being used to cure deafness in new gene therapy. Researchers also discovered that a plant virus could be used to save crops from root-eating pests.
Genetically-engineered skin bacteria keep some mosquitoes away. Scientists have genetically engineered a fly species to eat more waste. A genetically-modified chicken lays eggs that people allergic to eggs can eat.
Scientists have genetically engineered a cow that produces human insulin in its milk.
Genetic engineering recently produced bacon and pork that people who are allergic to red meat can eat.
A genetically-engineered apple doesn’t turn brown when you slice it, the way most apples do.
