What role do our genes play in intestinal health?

A new study published today in Nature Genetics sheds light on the impact of our genes on our gut health and their involvement in determining the composition of our gut flora.

We’ve long known that what we consume has a significant impact on the composition of our gut microbiota, but the role of our own genes is still unknown.

This new study finds a substantial link between the prevalence of specific microorganisms in our gut and the presence of certain genes that vary by population, including genes that are closely linked to disorders like lactose intolerance and blood type.

The authors used high-performance computing to analyze large genomic and microbiome datasets, led by the Cambridge-Baker Systems Genomics Initiative, which included researchers from the Baker Heart and Diabetes Institute in Melbourne and the University of Cambridge in the United Kingdom, as well as researchers from the Universities of Helsinki, Turku (Finland), and the University of California San Diego (USA).

Previous research on how human genetic variation affects gut microbiota has shown an ambiguous and complex interaction between environment and genetics, which the authors attempted to elucidate with a large sample size dataset.

Researchers analyzed the microorganisms in the gut, dietary information, and health records of nearly 6000 people from various geographical areas of Finland over a 16-year period using a large-scale population cohort dataset from the internationally renowned FINRISK Study (a large Finnish population survey).

Dr. Guillaume Meric, a Baker Institute researcher and microbiologist who co-led the study, said it was one of the largest of its kind and provided statistically robust findings from a large representative population survey, allowing for a better understanding of the role of genes on our gut microbiota.

Huge computer capabilities paired with more affordable sequencing for a large number of samples, according to Dr. Meric, have made this a hot area of study, with several comparable high-impact studies being published, or about to be published.

He explained that the researchers were able to characterize human genetic variations associated with varying concentrations and diversity of microbes in the gut, as well as predict possible causative or protective links between specific gut microbes and various diseases, thanks to the deep data dive.

According to Dr. Meric, the study found a number of extremely significant links between genes, gut microbes, and a variety of diseases and disorders, with intriguing candidates associated with lactose intolerance, colorectal cancer, and major depressive disorder.

The researchers discovered 567 different genetic variations linked to levels of more than 200 bacteria species in the gut, and the publication opens up new avenues for research into how we might diagnose and treat diseases using these potent genetic and microbial insights.

“For hundreds of thousands of years, humans have co-evolved with the bacteria that live within and on us. This has resulted in a finely tuned equilibrium between our bacteria, genes, food, and health that is still difficult to untangle and research to this day.

Investigating very big datasets of several thousand people to robustly uncover common relationships is one viable technique to shed additional insight on this remarkable association. Several other recent research involving people from different parts of the world have already confirmed our findings.

This collection of studies, taken together, exemplifies the complex link that exists between humans and their gut microbial ecosystems, as well as highlighting crucial health consequences “Dr. Meric came to a conclusion.