- Environmental conditions
Is our gut flora determined randomly?
With our growing understanding of the gut-brain axis, the relationship of intestinal flora and of our control center has been slowly revealing itself to be complex.
We now know that gut bacteria can influence our behavior and even determine what our disease risk. But despite these understandings, we are still learning what factors account for the individual differences humans have in terms of behavior and medical conditions.
Fortunately, the mystery of heterogeneity, the difference between individuals, can now be explained with a study done by the Massachusetts Institute of Technology. In their study, researchers set out to answer the question on why despite having the same diet and environmental exposure, humans still experience drastic differences within the species in terms of gut flora.
As it turns out, the answer is as random as the word random itself; the reason behind it is simply put, chance. In the study, the researchers used genetically identical worms fed the same diet and kept in the same environmental condition. However, despite strict controls, the worms developed distinct and different populations of bacteria in their gut. As it turns out, the population growth is determined by which bacteria is able to colonize the gut first and that the type of gut flora that grows depends on chance.
The researchers on the study were able to confirm this by ingeniously giving the worms marked with two fluorescent proteins of different colors. One red and the other green. Those who had been colonized first by the green marked bacteria developed a green gut population and those with red also developed that specific red population.
This confirms the theory that despite having generally similar diets and environmental exposure, the factor of chance plays a bigger role than we first thought.
Stochastic assembly produces heterogeneous communities in the Caenorhabditis elegans intestine