Sequencing the mouse genome for the oxidatively modified base 8-oxo-7,8-dihydroguanine by OG-Seq

Oxidative damage to the genome can yield the base 8-oxo-7,8-dihydroguanine (OG). A method was developed to sequence OG on the genome scale at a resolution of 150 base pairs that we call OG-Seq. This approach applied to genomic DNA derived from mouse embryonic fibroblasts (MEFs) to obtain ~10,000 regions of OG enrichment. Additionally, MEF cells with the OG specific repair glycosylase Ogg1 knocked out were sequenced by OG-Seq to identify ~18,000 regions enriched in OG. Inspection of the genomic regions in which the OG enriched peaks were located found gene promoters and UTRs to harbor more OG than expected if OG was randomly distributed. Furthermore, OG-enriched regions were found to correlate with reactive 5`-GG-3` sequences, a result supporting decades of in vitro studies.