Abasic site
Definition
A position in the DNA backbone where the nitrogenous base has been lost, leaving only the deoxyribose-phosphate scaffold. Also called an AP (apurinic/apyrimidinic) site. Abasic sites block most DNA polymerases and are chemically labile, breaking the backbone under alkaline conditions.
Related terms
- 8-Oxoguanine
- An oxidised form of guanine produced by reactive oxygen species attacking the C8 position of the guanine ring. 8-Oxoguanine mispairs with adenine...
- Depurination
- Hydrolytic cleavage of the N-glycosidic bond between deoxyribose and a purine base (adenine or guanine), generating an abasic (apurinic) site. Abasic sites...
- Internal positive control (IPC)
- An exogenous DNA template of known sequence and concentration added to the PCR reaction alongside the forensic sample. If the IPC fails...
- Ministr (reduced-size) STR
- A short tandem repeat assay redesigned so that the amplicon spans a shorter distance from primer to primer, typically less than 200...
- PCR inhibitor
- A co-extracted substance that interferes with Taq polymerase activity or primer annealing. Common inhibitors in forensic samples include haemoglobin (from blood on...
Explained in
- DNA Degradation: Mechanisms, Inhibitors and Environmental EffectsA position in the DNA backbone where the nitrogenous base has been lost, leaving only the deoxyribose-phosphate scaffold. Also called an AP (apurinic/apyrimidi...