Scientists Have Discovered "Clocks" Inside Your Cells That Could Determine When You Get Cancer

External factors like the Sun and smoking can harm your DNA by causing mutations, a process that occurs in spurts and bursts. But this process isn't limited to environmental triggers: As cells grow and divide, internal factors also cause the cell to continuously generate mutations at a constant rate. These steady mutations, which occur in a “clock-like” way, correlate to a person’s age: The older you are, the more mutations you acquire.