What tangled web: barriers to rampant horizontal gene transfer
✍ Scribed by Charles G. Kurland
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 85 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0265-9247
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Dawkins in his The Selfish Gene^(1)^ quite aptly applies the term “selfish” to parasitic repetitive DNA sequences endemic to eukaryotic genomes, especially vertebrates. Doolittle and Sapienza^(2)^ as well as Orgel and Crick^(3)^ enlivened this notion of selfish DNA with the identification of such repetitive sequences as remnants of mobile elements such as transposons. In addition, Orgel and Crick^(3)^ associated parasitic DNA with a potential to outgrow their host genomes by propagating both vertically via conventional genome replication as well as infectiously by horizontal gene transfer (HGT) to other genomes. Still later, Doolittle^(4)^ speculated that unchecked HGT between unrelated genomes so complicates phylogeny that the conventional representation of a tree of life would have to be replaced by a thicket or a web of life.^(4)^ In contrast, considerable data now show that reconstructions based on whole genome sequences are consistent with the conventional “tree of life”.^(5–10)^ Here, we identify natural barriers that protect modern genome populations from the inroads of rampant HGT. BioEssays 27:741–747, 2005. © 2005 Wiley Periodicals, Inc.