The Flemish Gut Flora Project Is Flourishing

26 August 2016
​Did you know that one of the world’s largest gut microbiome research efforts is run by a VIB lab? Jeroen Raes and his team started a bottom-up initiative in 2012 that would soon turn out to be a huge research project involving the collection of thousands of Flemish stool samples. The goal of the Flemish Gut Flora Project? To investigate the links between the billions of gut bacteria, health and lifestyle. The project’s first extensive paper was released in April and was immediately a massive hit in scientific circles – and beyond.

Published in Science, the study identified 69 factors associated with the volume and diversity of gut flora, most of which are related to stool transit time, diseases, food intake, the use of medicine, and age. However, despite the incredible efforts of the Gut Flora team and the 5,000 Flemish volunteers who participated in the project, only 7% of gut flora variation has currently been mapped out. In other words: we are only seeing the tip of the iceberg. This is why Jeroen and his team (VIB/KU Leuven) are now pushing full steam ahead to recruit new volunteers.
But who can describe the ins and outs of this great feat better than our researchers themselves?

Where did your fascination with gut flora come from?
Gwen Falony (staff scientist and co-first author): “When I was six, I fell in the septic tank of my grandparents’ farm – luckily it was empty. The family legend states that in the end they found me in the tank, playing with disgusting bugs and repulsive insects. I don’t remember much of the incident, but one could say my future as a gut microbiota researcher was just meant to be.”

What were the biggest hurdles in this project?
Jun Wang (postdoc and co-first author): “For me, collecting all the data (online and on paper) and organizing them into forms that a statistician can work with was the real challenge. At the time, every step was new. But when the first results started to show up, we knew we’d been successful.”

What is it like to do science together with and thanks to thousands of volunteers?
Sara Viera-Silva (postdoc and co-first author): “Although setting up such a large-scale project was definitely a logistic challenge, we feel very grateful for their participation and their support on social media. Moreover, our volunteers were an extra motivation to finalize this first publication and communicate our results. We hope that these will answer some of their questions, and reinforce their curiosity about gut flora.”

How does it feel to publish these first results?
Marie Joossens (postdoc and co-first author): “We’re very proud! Because we knew that we were competing with international groups with bigger resources, we focused on high quality data. When we could confirm our results with those of an independent Dutch cohort, we knew that all of our efforts had been worthwhile!”

Can you briefly describe the samples’ journey from volunteer to the lab?
Chloë Verspecht (Lab Technician): “The initial plan was to invite participants to deposit their sample in a VIB bus that would be parked on a central square in their hometown. But that wouldn’t be very practical. Based on a suggestion of a pharmacist, we set up several collection points in pharmacies. There, the fecal material was frozen, after which we collected the samples and transported them to our lab on a regular basis. Blood samples came through the primary care physicians of the participants, together with the medical questionnaires.”

Leen Rymenans (Lab Technician): “So you can see the logistics of this study was very challenging – but we managed thanks to the help of all these doctors and pharmacists! After that, our hard work started: dealing with all the incoming packages, manually aliquoting thousands of samples, DNA extraction, quality control, PCRs, library prep and sequencing – and not switching a simple sample thanks to the barcoding system we put in place!”

What will the future bring?
Jeroen Raes: “There is still so much we want to do! First of all, we still have a few thousand samples to analyze that were not part of this first paper. Secondly, we realized that we probably need to include ten thousands of additional people to get the full picture. Third, we are already following up some clues from this paper in target studies. But the thing I’m really interested in is the dynamics – what will these peoples’ microbiota look like in a year, two years from now? How stable is the microbiota and what is the time scale? Can we predict future health of these individuals from current samples? And a million other questions – this is really just the start!”


Marie Joossens, Jeroen Raes, Jun Wang, Leen Rymenans, Sara Vieira-Silva, Gwen Falony and Chloë Verspecht