In a recent study, researchers linked the genetic makeup of bacteria in the human gut to several human diseases, proposing what they called microbiome disease architectures.
Microbiome disease architectures
Humans are host to trillions of bacteria, fungi, viruses and other microorganisms that make up the human microbiome. Several studies in recent years have linked the presence of specific microorganisms with a range of conditions, including obesity and multiple sclerosis.
In this study, published in Nature Communications, researchers expanded on this work by going beyond the microbial species and analysing the genetic material of bacteria in the gut. The team introduced microbiome architectures, which are analogous to human genetic architectures. They are the characteristics of the microbiome, which in combination correlate with human phenotype.
Genetic signatures
The team began by collecting microbiome data from 13 groups of patients (more than 2,500 samples). They then analysed the data to identify links between 7 host phenotypes and 1 million microbial features (species, pathways and genes). By using a variety of modelling approaches, they were able to observe what microbiome features emerged as the strongest disease-associated candidates. This allowed them to identify groups of bacterial genes (genetic signatures) that were linked closely to a given condition, rather than merely the presence of certain bacterial families.
From this, they found that coronary artery disease, inflammatory bowl disease and liver cirrhosis share gene-level signatures ascribed to the Streptococcus genus. In contrast, the metagenomic signature for type 2 diabetes was distinct and did not link to any one specific species or genus.
In addition, unlike previous reports, the analysis did not find a consistent link between the presence of bacterial species Solobacterium moorei and colon cancer. However, the researchers did find specific genes from a S. moorei subspecies associated with colorectal cancer. This suggests that a gene-level analysis may yield biomarkers of disease with greater precision and more specificity than current approaches.
Overall, the new findings represent a major step forward in understanding the complexity between human diseases and the gut microbiome.
Co-senior author of the study, Chirag Patel, stated:
“Our study underscores the value of data science to tease out complex interplay between microbes and humans.”
Image credit: By Science Photo Library – canva
