Scientists at the University of Colorado in Boulder (UCB) have recently developed a new model to explain how bacteria are distributed across the human body, which may bring forth a new wave of understanding of how the microorganisms either live with us in symbiosis, or cause us significant damage. The team has also managed to determine which of the bacteria populations aid us in fulfilling certain physiological functions, and which just hike along for the ride.

“This is the most complete view we have yet of the microbial side of ourselves, one that our group and others will be adding to over the coming years. The goal is to find out what is normal for a healthy person, which will provide a baseline for further studies to look at people with diseased states. One of the biggest surprises was how much variation there was from person to person in a healthy group of subjects,” Rob Knight says.

The expert is a UCB Chemistry and Biochemistry Department assistant professor, and also the senior author of a new scientific paper detailing the finds that appears in the November 6 issue of the famous journal Science Express. The work shows that the human body does not carry the same bacterial cultures on all of its regions. The species we have on our head are fairly different from the ones on our feet, and those on the outside of the body differ greatly from the ones in the mouth, nose and stomach.

“We have an immense number of questions to answer. Why do healthy people have such different microbial communities? Do we each have distinct microbial signatures at birth, or do they evolve as we age? And how much do they matter? We just don't know yet,” UCB Ecology and Evolutionary Biology Department Assistant Professor Noah Fierer, also a coauthor of the new Science Express paper, shares.

The new study is very important because, as soon as this distribution is better understood, experts will be able to start looking for various biomarkers associated with individual diseases. The conditions will be identified faster in the future, giving the patients more time to seek appropriate treatments, and increasing their chances of survival.