You have roughly 69,000,000,000,000 (69 trillion) cells in your body, but only about half of those are human cells. The rest are bacterial cells and this does not even include the many viruses living within you. Our body is filled with tiny bacteria and other microorganisms (microbes), collectively called our microbiome.
This small ecosystem features the collection of bacteria, viruses, and other microscopic organisms that live in the human body. They perform crucial tasks that help keep us alive. Bacteria in your intestines are the reason you can digest complex carbohydrates like starch. Scientists accidentally discovered that almost all of the microbes are unknown to science.
What was the Research?
The researchers were trying to find for an easy way to know when a patient’s body is about to reject a transplant. They took blood samples from transplant recipients, analyzed their microbiome and found that if the blood contained a lot of DNA from the organ donor, the organ was probably about to be rejected.
The team collected samples from 156 people undergoing organ transplants. They could identify DNA from the patient, from the organ donor, and from the bacteria living inside the patient’s body. They found that 99% of the DNA they collected failed to match anything in their database. It means this was completely unknown to science.
The majority of this non-human DNA belonged to a type of bacteria called proteobacteria, to which E. coli and Salmonella belongs. Scientists also found a group of viruses that belong to Torque Teno family, which are not generally associated with the disease.
Why were so many microbes unknown?
Most studies are usually very focused on one particular part of the microbiome or body and dismiss anything not directly related to their main experiments. They look at only the skin, or only the gut, or only one kind of microbe. Because the team used a wider lens in their transplant study, they found a lot of microbes that scientists had never thought to analyze before.
Knowing more about the grand diversity of the human microbiome can spot future infectious diseases before they happen or help doctors identify the bacteria or virus responsible. This can help experts prevent the next global pandemic. This research also opens up a brand new avenue of research for scientists looking to understand the microbiome.