Evolutionary Causes and Consequences of Stress-Induced Hypermutation

2012-11-22T18:35:12Z (GMT) by Yoav Ram Lilach Hadany
<p>This presentation was given at the 1st Graduate Students' Conference in Genetics, Genomics and Evolution at the Ben-Gurion University of the Negev, Be'er-Sheva, Israel, September 23, 2012.</p> <p>Abstract:</p> <p>Numerous empirical studies show that stress of various kinds induces a state of hypermutation in bacteria via multiple mechanisms, but theoretical treatment of this intriguing phenomenon is lacking. </p> <p>We used deterministic and stochastic models to study the evolution of stress-induced hypermutation in finite and infinite size populations of bacteria undergoing selection, mutation, recombination, and random genetic drift in constant environments and in changing ones. </p> <p>Our results suggest that stress-induced mutagenesis is advantageous for bacteria at both the individual and the population levels and that it is likely to evolve in natural populations in a wide range of conditions because it is favored by selection. </p> <p>These results imply that mutations are not, as the current view holds, uniformly distributed in populations, but rather that mutations are more common in stressed individuals and populations. This has a significant impact on a various aspects of evolution, genetics, and biology. </p>