The ability of cells to fully and faithfully replicate DNA is essential for preventing genomic instability and cancer. DNA is susceptible to damage both in resting and in actively replicating cells. Thus, genome duplication necessarily involves replication of damaged DNA. The many mechanism cells use to avoid or overcome the problems of replicating an imperfect DNA template are discussed.

We report on modulational instability (MI) on a DNA charge transfer model known as the Peyrard-Bishop-Holstein (PBH) model. In the continuum approximation, the system reduces to a modified Klein-Gordon-Schrödinger (mKGS) system through which linear stability analysis is performed. This model shows some possibilities for the MI region and the study is carried out for some values of the nearest-n...

In the September 26 issue of Science, McMurray and Gottschling (2003) report that aged yeast cells display high rates of loss of heterozygosity. Furthermore, they show that this reflects an impaired ability to correctly detect and repair DNA double-strand breaks. These results provide insights into how aging can engender genomic instability in eukaryotic cells.