Mapping the DNA damage caused by smoking cigarettes

A research team headed by Nobel laureate Aziz Sancar, MD, PhD, the Sarah Graham Kenan Professor of Biochemistry and Biophysics at UNC's School of Medicine has created a method that maps DNA damage due to cigarette smoking across the genome. Researchers have been aware of the DNA damage that smoking causes. Sancar’s technique pinpoints the exact locations on the genome that are undergoing repair due to the DNA damage. Smoking delivers benzo[α]pyrene (BaP) into the human tissue, and the blood’s enzymes try to break it down into less harmless molecules. This renders a compound called benzo[α]pyrene diol epoxide (BPDE) in the blood, which is more harmful than BaP. BPDE can cause cancerous growth as it reacts chemically with DNA and prevents it from duplicating properly during cell division. When this happens, the cell attempts nucleotide excision repair, which refers to the special proteins attempting to rid the affected DNA strand. With the new technique, these affected DNA strands can be collected and studied to know the sites where the DNA damage was caused. This would aid the development of targeted therapies to combat DNA damage, understanding the origination of cancer due to smoking, and the reasons for the predisposition of some people to cancer.  

Read more in Science Daily.