DNA adduct

In molecular genetics, a DNA adduct is a piece of DNA covalently bonded to a (cancer-causing) chemical. This process could be the start of a cancerous cell, or carcinogenesis. DNA adducts in scientific experiments are used as biomarkers of exposure and as such are themselves measured to reflect quantitatively, for comparison, the amount of carcinogen exposure to the subject organism, i.e. rats or other living animals. Under experimental conditions for study, such DNA adducts are induced by known carcinogens, of which commonly used is DMBA (7,12-dimethylbenzanthracene). For example, the term "DMBA-DNA adduct" in a scientific journal refers to a piece of DNA that has DMBA attached to it. The presence of such an adduct indicates prior exposure to a potential carcinogen, but does not by itself indicate the presence of cancer in the subject animal .

Examples

Chemicals which form DNA adducts include:

• acetaldehyde, is a significant constituent of tobacco smoke
• cisplatin binds to DNA and causes crosslinking, leading to death of the cell
• DMBA (7,12-dimethylbenzanthracene)
• malondialdehyde, a naturally occurring product of lipid peroxidation

DNA adducts include:

• etheno-DNA adducts: 1,N(6)-etheno-2'-deoxyadenosine (epsilondA) and 3,N(4)-etheno-2'-deoxycytidine (epsilondC)

By-products include:

• M₁G, a by-product of base excision repair (BER) of a specific type of......
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