As more research was done, they discovered that viruses do not cause all types of cancer but they can cause some, such as HPV that causes cervical cancer. When it came to the chemicals, they also discovered that chemicals do, in fact, cause cancer. One of the biggest discoveries about chemicals was that smoking cigarettes can actually cause lung cancer. That idea/theory was proven because many doctors asked their patients that had lung cancer about their habits and discovered the the only thing that all the patients had in common was that they smoked or were very heavy smokers. But it wasn’t only cigarettes that caused lung cancer, factory chemicals such as formaldehyde could also trigger cancer to take place. Finally, in late 1970s someone thought about chromosomal defects and how genes might be another cause of cancer. Bishop and Varmus discovered that there was an extra gene that caused cancer, an oncogene. The oncogene prior to becoming one, it was a proto-oncogene, a normal gene that is already in the human body. This discovery allowed researchers and doctors to know that the possible genes that caused cancer are already residing in the human body, and are not coming from external factors, but they are just mutated. A young cancer researcher, Weinberg discovered the first human oncogene,
As more research was done, they discovered that viruses do not cause all types of cancer but they can cause some, such as HPV that causes cervical cancer. When it came to the chemicals, they also discovered that chemicals do, in fact, cause cancer. One of the biggest discoveries about chemicals was that smoking cigarettes can actually cause lung cancer. That idea/theory was proven because many doctors asked their patients that had lung cancer about their habits and discovered the the only thing that all the patients had in common was that they smoked or were very heavy smokers. But it wasn’t only cigarettes that caused lung cancer, factory chemicals such as formaldehyde could also trigger cancer to take place. Finally, in late 1970s someone thought about chromosomal defects and how genes might be another cause of cancer. Bishop and Varmus discovered that there was an extra gene that caused cancer, an oncogene. The oncogene prior to becoming one, it was a proto-oncogene, a normal gene that is already in the human body. This discovery allowed researchers and doctors to know that the possible genes that caused cancer are already residing in the human body, and are not coming from external factors, but they are just mutated. A young cancer researcher, Weinberg discovered the first human oncogene,