One of the issues that scientists have been working on for many years is what causes bladder cancer. Although it is still difficult to make a firm claim, smoking is considered to be the main risk factor for the disease. Scientists from the University of York, Canada, developed bladder tissues in a laboratory setting, subjecting it to non-toxic toxic particles. With the obtained result, it is thought that an important threshold may have been exceeded in bladder cancer research. Dr. In the study conducted by Simon Baker and colleagues, the genetic code (DNA) consisting of 3 billion letters was examined after the tissues exposed to cigarette poisons were damaged. This investigation was carried out to find patterns of change called ‘mutation signature’. Dr. Baker likens mutation signatures to fingerprints at a crime scene. When you look at the DNA in a cancer, you can see the fingerprints of all the criminals causing cancer. Smoking may not be the main risk factor for bladder cancer: Dr. Baker said DNA damage could be caused by toxins in cigarettes or ultraviolet rays from the sun, as well as even a completely unknown source. According to the research, cigarette poisons leave their distinctive fingerprint on the DNA of the bladder tissues produced in the laboratory. However, when examining the DNA in the bladder of a patient with bladder cancer, it appears that the cigarette venom causes only a small amount of damage. Dr. Although Baker’s conclusion is that smoking is one of the main risk factors for bladder cancer, direct damage to cigarette poisons DNA is not the main reason for the development of this cancer. Perhaps cigarette poisons are speeding up other DNA damage. Scientists will now focus on a family of enzymes called ‘APOBEC’. APOBEC enzymes mutate the DNA of the virus, destroying that virus, and this is one of the main responses of our immune system to infections, but based on recent research, this family of enzymes may accidentally target our own DNA in some types of cancer. In the next step of the research, it will be aimed to understand how and why APOBEC enzymes are activated in bladder cells.