Question

What is the "tumor suppressor gene" responsible for shutting down the cell cycle in G1 if too much DNA damage is present?

Answer 1

The answer is the p53 gene. The p53 gene is a tumor suppressor gene that plays an important role in regulating the cell cycle. If DNA damage is detected in the cell, the p53 gene is activated and triggers the cell cycle to stop in the G1 phase. This gives the cell time to repair the damage or, if the damage is too severe, the p53 gene can trigger apoptosis or programmed cell death. Essentially, the p53 gene acts as a quality control mechanism for the cell, ensuring that damaged cells don't divide and potentially cause cancer.