Quantifying the Extent of Lateral Gene Transfer Required to Avert a `Genome of Eden'

Leo van Iersel; Charles Semple; Mike Steel

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arXiv · 0911.1146

Quantifying the Extent of Lateral Gene Transfer Required to Avert a `Genome of Eden'

Leo van Iersel·Charles Semple·Mike Steel

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Abstract

The complex pattern of presence and absence of many genes across different species provides tantalising clues as to how genes evolved through the processes of gene genesis, gene loss and lateral gene transfer (LGT). The extent of LGT, particularly in prokaryotes, and its implications for creating a `network of life' rather than a `tree of life' is controversial. In this paper, we formally model the problem of quantifying LGT, and provide exact mathematical bounds, and new computational results. In particular, we investigate the computational complexity of quantifying the extent of LGT under the simple models of gene genesis, loss and transfer on which a recent heuristic analysis of biological data relied. Our approach takes advantage of a relationship between LGT optimization and graph-theoretical concepts such as tree width and network flow.

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Leo van Iersel, Charles Semple, Mike Steel. 2009-11-05. Quantifying the Extent of Lateral Gene Transfer Required to Avert a `Genome of Eden'. https://arxiv.org/abs/0911.1146

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