Gene-Specific and Mitochondrial Repair of Oxidative DNA Damage

DNA repair is a heterogeneous process. The efficiency of repair differs not only with lesion type, but also with genomic location. Protein coding regions of the genome are repaired more efficiently than noncoding regions in a process termed preferential repair. Furthermore, for many lesions, there is a hierarchy even within the coding regions. A process termed transcription-coupled repair allows active genes to be repaired more rapidly than inactive genes, and the transcribed strand to be repaired with greater efficiency than the nontranscribed strand (1 ).