Science & Tech · Science & Environment · 18 hrs ago
Gut bacteria in industrialized communities carry more recently acquired genes
Researchers examined 5,981 gut bacterial genomes collected from people in nine countries.
In all ten closely studied bacterial species, strains from industrialized communities carried more protein-coding genes than strains from non-industrialized communities.
The extra genes were optional genes, which some strains have and others do not.
The team found that most gene gains happened recently, rather than being passed down from parent bacteria.
An estimated 80% to 90% of these gains came through gene transfers from other microbes.
The findings suggest that modern living is changing bacterial genomes, as well as which bacteria live in people’s guts.
The study measured bacterial genes, not people’s health, so it does not show whether the changes are beneficial or harmful.
A study of 5,981 gut bacterial genomes found that strains from industrialized communities carried more genes than strains from non-industrialized communities.
Most of the additional genes appeared to have been acquired recently from other microbes.
The difference involved optional genes, while core genes showed no difference.
The researchers found the pattern across ten species and saw it again in a comparison of 34 species.
The findings describe bacterial genomes and do not show whether larger genomes affect people’s health.
- Who
- Researchers at Kiel University’s Institute of Clinical Molecular Biology and MIT’s Department of Biological Engineering conducted the study, with evolutionary modeling done in Japan.
- What
- The study found that gut bacterial strains from industrialized communities carried more genes, most acquired recently from other microbes.
- When
- Not stated.
- Where
- The study used samples from Cameroon, Ghana, Malaysia, Nigeria and Rwanda, and genomes from donors in nine countries.
- Why
- The researchers examined whether gut bacteria themselves had evolved in response to differences in how people live.
This story does not have two clearly opposing sides.
Twenty volunteers in Cameroon, Ghana, Malaysia, Nigeria and Rwanda provided stool samples.
Scientists processed the samples on site and then froze them in liquid nitrogen.
Bacterial colonies grew in an oxygen-free chamber before individual colonies were sequenced.
The researchers compared bacterial genomes from industrialized and non-industrialized communities.
- Total genomes
- 5,981
- New genomes
- 1,841
- Existing banked strains
- 4,140
- Species in initial comparison
- 10
- Species in wider comparison
- 34
- Gene gains from transfers
- 80% to 90% of gains among industrialized-host branches