The wolves are exposed to cancer-causing radiation as they roam the wastelands of the abandoned city - with researchers finding part of their genetic information seems resilient to increased risk of the disease.
And that trait does exist in nature already, it’s just rare and mostly useless until environmental pressures only allow those individuals to reproduce.
Only if you have some individuals with [cancer or whatever] resistance though.
Everyone has “cancer or whatever” resistance. That’s why DNA works, it has repair mechanisms.
Getting cancer is when that mechanism either fails or isn’t good enough to repair the damage.
Radiation can cause an excess of damage or different type of damage than what your natural mechanism is capable of fixing.
And that trait does exist in nature already, it’s just rare and mostly useless until environmental pressures only allow those individuals to reproduce.