DNA adducts

DNA adducts are chemical modifications of DNA. A chemical modification on the DNA strand may hinder DNA replication (like when you get something caught in your jacket zipper), resulting in abnormal replication and mutation.

The formation of the adduct in cells does not mean an individual will develop cancer. The DNA is constantly being damaged. The body has systems in place which can repair damaged DNA or induce the death of cells with high levels of DNA damage. Continuous exposure to the environments and substances that lead to the formation of adducts (e.g. through poor diet and lifestyle) can in the long-term lead to a greater chance of proliferation of cells with damage in genes that make it susceptible to becoming cancers. This is a process that can take decades.

DNA adducts can be detected using a method called, immunohistochemistry. In this method, a tissue of interest is embedded into media on microscope slides. Then, an antibody specific for the DNA adduct is applied. Next, a specific stain is added to the slides. In places where the antibody has bound to tissue containing DNA adducts, the stain will show a red colour. Parts of the tissue that have no DNA adducts will be coloured blue by the stain.

Diet modulates levels of DNA adducts in our body.

References:

• Le Leu, R.K., Winter, J.M., Christophersen, C.T., Young , G.P., Humphreys, K.J., Hu, Y., Gratz, S.W., Miller, R.B., Topping, D.L., Bird, A.R., Conlon, M.A. “Butyrylated Starch Intake Can Prevent Red Meat-Induced O6-Methyl-2-Deoxyguanosine Adducts in Human Rectal Tissue: a Randomised Clinical Trial.” British Journal of Nutrition, vol. 114, no. 02, 2015, pp. 220–230., doi:10.1017/s0007114515001750.