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Abstract Horizontal gene transfer (HGT) is a fundamental ecological and evolutionary process involving the movement of genetic material across taxa within a single generation. While traditionally studied at the level of individual genes with encoded adaptive functions, recent advances in genomics and metagenomics highlight the need for a broader, integrative framework. Here, we expand the concept of the “ecology of DNA transfer,” which conceptualizes HGT as a multi-layered process spanning the genome, cell, and ecological context. We further explore how the fate and expression of transferred DNA vary over evolutionary timescales, from recently acquired, transcriptionally silenced sequences to ancient, fully integrated genes. Together, this framework underscores HGT as a dynamic, context-dependent process shaped by interactions across biological scales.
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This content will become publicly available on June 1, 2027
The ecology of horizontal gene transfer
Horizontal gene transfer (HGT) generates genetic variation in populations across all domains of life; however, most studies focus on individual transfers and functional information derived therefrom. This is useful but does not consider DNA transfer more broadly, that is, nongene transfers, donor–recipient dynamics, or trends and background levels that may help infer ecological information. Here, we review the mechanistic underpinnings of DNA transfer, literature from diverse fields that addresses HGT on a community basis and the associated methodological challenges, and propose a framework for conceptualizing the process of DNA transfer, highlighting DNA mobility as a feature of community ecology and DNA itself as a public good. These ideas coalesce to support DNA transfer as a fundamental ecological phenomenon that remains largely unmeasured.
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- Award ID(s):
- 2410358
- PAR ID:
- 10703728
- Publisher / Repository:
- Trends in Genetics
- Date Published:
- Journal Name:
- Trends in Genetics
- Volume:
- 42
- Issue:
- 6
- ISSN:
- 0168-9525
- Page Range / eLocation ID:
- 539 to 554
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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