DNA repair nucleotide-excision repair Note that although intrastrand cross-link repair is not exactly synonymous with nucleotide excision repair, nucleotide excision repair includes the repair of intrastrand cross-links. The synonym field is being used to reflect the broad substrate specificity of nucleotide excision repair. pyrimidine-dimer repair, DNA damage excision intrastrand cross-link repair biological_process GO:0045001 Reactome:R-HSA-5696400 Reactome:R-HSA-5696398 GO:0006289 A DNA repair process in which a small region of the strand surrounding the damage is removed from the DNA helix as an oligonucleotide. The small gap left in the DNA helix is filled in by the sequential action of DNA polymerase and DNA ligase. Nucleotide excision repair recognizes a wide range of substrates, including damage caused by UV irradiation (pyrimidine dimers and 6-4 photoproducts) and chemicals (intrastrand cross-links and bulky adducts). NER