Figure 1.

Transition Mutations, and Especially Transversion Mutations, Are Enriched in Late S Phase

(A) The replication time of chromosome 5 along with the density of cell line mutations. The density of mutations is shown in reverse scale (i.e., higher mutation rates are shown lower on the plot), as mutation rate per 100 Kb windows (smoothed over 40 windows) in all cell lines combined.

(B) Distribution of DNA replication timing for the entire genome (gray; mean set to 0) and for cell line mutation locations (green: transitions; red: transversions): transitions, and especially transversions, show a strong bias toward late S phase.

(C) The average replication timing structure in the region extending to 3 megabases of both sides of all mutation locations. In dashed lines are the same plots for 20 sets each of random genomic locations matching in number to the mutation events of the different types.