Past research has suggested that weight may be influenced by genes. A new study builds on this concept, revealing that our genetic makeup shapes what type of bacteria live in the gut, which may affect how heavy we are.
The findings come from a twin study conducted by researchers from Cornell University in Ithaca, NY, and King's College London in the UK.
The research team, including Prof. Tim Spector, head of the Department of Twin Research and Genetic Epidemiology at King's College London, says the results may open the door to personalized probiotic treatments that could reduce the risk of obesity and its related diseases.
Results of the analysis revealed that identical twins had a similar abundance of specific types of gut bacteria, compared with non-identical twins. The team says this indicates that genes influence the type of bacteria present in the gut.
What is more, the researchers found that the presence of a class of bacteria called Christensenellaceae was most influenced by genes. A certain strain of this bacteria - Christensenellaceae minuta - was found to be more common among individuals of a low body weight.
On introducing this bacteria to the guts of mice, the team found the animals gained less weight than those that did not receive the bacteria. This suggests that increasing the amount of Christensenellaceae minuta bacteria in the gut could help to reduce or prevent obesity, the researchers say.
Commenting on their results, Prof. Spector says:
"Our findings show that specific groups of microbes living in our gut could be protective against obesity - and that their abundance is influenced by our genes. The human microbiome represents an exciting new target for dietary changes and treatments aimed at combating obesity."
Senior author Ruth Ley, an associate professor of microbiology at Cornell University, notes that this study is the first to determine that specific gut microbes are heritable and that the variation of these microbes is not solely influenced by diet, environment, lifestyle and health.