What can lead to deleterious mutations?

High mutation rates can lead to deleterious mutations because the likelihood of generating errors in DNA replication increases with the frequency of mutations. While some mutations may be neutral or beneficial, others can disrupt gene function, leading to negative consequences for the organism.

When mutation rates are high, the chance of acquiring mutations that negatively impact essential biological processes—such as protein folding, enzyme function, or regulatory mechanisms—goes up significantly. These deleterious mutations can decrease an organism's fitness or survivability in its environment.

Consequently, while mutations are a fundamental source of genetic variation and evolutionary change, an elevated mutation rate can overwhelm the beneficial or neutral effects of genetic variation, leading to a higher incidence of harmful effects overall.