Edinburgh Research Explorer

Lagging strand replication shapes the mutational landscape of the genome 


Related Edinburgh Organisations

PublisherEdinburgh DataShare
Date made available26 Jan 2015


The origin of mutations is central to understanding evolution and of key relevance to health. Variation occurs non-randomly across the genome, and mechanisms for this remain to be defined. Here we report that the 5' ends of Okazaki fragments have significantly increased levels of nucleotide substitution, indicating a replicative origin for such mutations. Using a novel method, emRiboSeq, we map the genome-wide contribution of polymerases, and show that despite Okazaki fragment processing, DNA synthesized by error-prone polymerase-alpha (Pol-alpha) is retained in vivo, comprising ~1.5% of the mature genome. We propose that DNA-binding proteins that rapidly re-associate post-replication act as partial barriers to Pol-delta-mediated displacement of Pol-alpha-synthesized DNA, resulting in incorporation of such Pol-alpha tracts and increased mutation rates at specific sites. We observe a mutational cost to chromatin and regulatory protein binding, resulting in mutation hotspots at regulatory elements, with signatures of this process detectable in both yeast and humans.

Data Citation

Taylor, Martin; Kemp, Harriet; Marion de Procé, Sophie; Reijns, Martin; Ding, James; Jackson, Andrew. (2015). Lagging strand replication shapes the mutational landscape of the genome, [dataset]. University of Edinburgh. MRC Institute of Genetics and Molecular Medicine. MRC Human Genetics Unit. http://dx.doi.org/10.7488/ds/204.

ID: 26341533