A major international study has identified 11 genetic variants that actively shape the human gut microbiome. By regulating the intestinal molecular environment, these genes influence bacterial composition and impact risks for cardiovascular disease and gluten intolerance.
Image Credit: Scientific Frontline
Scientific Frontline: Extended "At a Glance" Summary
The Core Concept: A comprehensive international study has identified 11 specific regions in the human genome that directly influence the composition and function of the gut microbiome. This research demonstrates that host genetics play a significant, specific role in determining which bacteria inhabit the intestines and how they operate.
Key Distinction/Mechanism: Unlike previous research, which had only confirmed two genetic regions linked to the microbiome, this study expands the known associations to 11 loci. The underlying mechanisms involve specific biological processes, such as determining which molecules appear on the surface of gut cells to serve as food for bacteria and regulating how the gut reacts to bacterial byproducts.
Origin/History: The findings were announced on February 16, 2026, following the publication of two coordinated studies in Nature Genetics led by researchers from Uppsala University, the University of Gothenburg, and the Norwegian University of Science and Technology (NTNU).
Major Frameworks/Components:
- Genome-Wide Association Analysis: Utilized data from over 28,000 individuals to map genetic variants to microbiome composition.
- Biobank Integration: Leveraged massive datasets from Swedish (SCAPIS, MOS, SIMPLER) and Norwegian (HUNT) population studies.
- Host-Microbe Interaction: Focused on genes affecting nutrient absorption and the intestinal molecular environment.
Branch of Science: Molecular Epidemiology, Human Genetics, Microbiology.
Future Application: These insights may facilitate the development of personalized therapeutic strategies that consider an individual's genetic predisposition to specific microbiome profiles. This could enhance prevention and treatment protocols for conditions deeply intertwined with gut health.
Why It Matters: The study establishes a clear biological link between specific genetic variants and an increased risk for diseases such as gluten intolerance, hemorrhoids, and cardiovascular disease. It provides a crucial piece of the puzzle in understanding how our DNA dictates our internal microbial ecosystem and, consequently, our overall health.
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| Tove Fall, Professor of Molecular Epidemiology. Photo Credit: Mikael Wallerstedt, Uppsala University |
In two new studies on 28,000 individuals, researchers can show that genetic variants in 11 regions of the human genome have a clear influence on which bacteria are in the gut and what they do there. Only two genetic regions were previously known. Some of the new genetic variants can be linked to an increased risk of gluten intolerance, haemorrhoids and cardiovascular diseases.
The community of bacteria living in our gut, or gut microbiome, has become a hot research area in recent years because of its great significance for health and disease. However, the extent to which our genes determine which bacteria are present in our intestines has been unclear. Until now, it has only been possible to link a few genetic variants to the composition of the gut microbiome with certainty.
Now, in two coordinated international studies, researchers have conducted the most comprehensive investigation so far of the link between the genome and the gut microbiome. The researchers have analyzed genetic data and gut bacteria from over 28,000 individuals. They have also carefully surveyed the bacteria the participants have in their intestines. Each individual carries hundreds of different bacteria species.
11 genetic regions play a role
The analysis identified 11 genetic regions that affect both the bacteria present in the gut and the roles they play. Several of the genes are associated with fundamental processes in the gastrointestinal tract, for example, how nutrients are absorbed and how the body reacts to the bacteria.
“We have learnt a lot about the role played by genetics in the gut microbiome. Several of the genetic connections that we found have to do with very specific biological mechanisms. These concerns, for instance, which molecules are present on the surface of gut cells and are thereby available as food for bacteria. They also relate to the way in which the gut reacts to molecules produced by bacteria,” says Tove Fall, Professor of Molecular Epidemiology at Uppsala University, who is responsible for one of the studies.
Clear associations to several diseases
The researchers also saw clear connections between some of the genetic variants and several diseases. The diseases investigated had been previously linked with the gut microbiome.
“We saw that some of these genetic variants were linked to the risk of gluten intolerance, haemorrhoids and cardiovascular diseases. This suggests that changes in the composition of intestinal bacteria could provide a way to better understand how genetic risks affect health,” says Claes Ohlsson, Professor at the University of Gothenburg, who led the other study together with Kristian Hveem, Professor at the Norwegian University of Science and Technology (NTNU).
One of the largest gut microbiome biobanks
The biobanks that the researchers have built up are among the largest in the world for gut microbiome.
“Given that many aspects of our health are linked to the gut microbiome, we naturally want our research to contribute to better ways of preventing and treating diseases by paying attention to the interaction between genes, gut biology and the microbiome,” says Fall.
Reference material: What Is: Human Microbiome
Additional information: The study involved a total of 28,669 individuals, 16,017 of whom were from Swedish population studies at Lund University (SCAPIS-Malmö, MOS) and Uppsala University (SCAPIS-Uppsala, SIMPLER) and 12,652 from the Trøndelag Health Study (HUNT).
Published in journal: Nature Genetics
Title:
- Genome-wide association analyses highlight the role of the intestinal molecular environment in human gut microbiota variation
- The HUNT study identifies host genetic factors reproducibly associated with human gut microbiota composition
Authors:
- Koen F. Dekkers, Kamalita Pertiwi, Gabriel Baldanzi, Per Lundmark, Ulf Hammar, Marta Riise Moksnes, Eivind Coward, Maria Nethander, Ghassan Ali Salih, Mariam Miari, Diem Nguyen, Sergi Sayols-Baixeras, Aron C. Eklund, Jacob Bak Holm, H. Bjørn Nielsen, Camila Gazolla Volpiano, Guillaume Méric, Manonanthini Thangam, Liisa Hakaste, Tiinamaija Tuomi, Emma Ahlqvist, Christopher A. Smith, Marie Allen, Frank Reimann, Fiona M. Gribble, Claes Ohlsson, Kristian Hveem, Olle Melander, Peter M. Nilsson, Gunnar Engström, J. Gustav Smith, Karl Michaëlsson, Johan Ärnlöv, Marju Orho-Melander, and Tove Fall
- Marta Riise Moksnes, Eivind Coward, Maria Nethander, Koen Dekkers, Louise Grahnemo, Anna E. Törnqvist, Lei Li, Per Lundmark, Kamalita Pertiwi, Gabriel Baldanzi, Robin Mjelle, Janne Marie Moll, Aron Charles Eklund, Henrik Bjørn Nielsen, Johan Svensson, Arnulf Langhammer, Guro F. Giskeødegård, Ben Brumpton, Rebecka Hjort, Eivind Ness-Jensen, Gunnar Engström, Thaher Pelaseyed, Karl Michaëlsson, Marju Orho-Melander, Tove Fall, Kristian Hveem, and Claes Ohlsson
Source/Credit: Uppsala universitet
Reference Number: mcb021726_02
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