A large fraction of germinal center B-cells acquire somatic mutations that prohibit antigen binding and these undergo apoptosis.

Evidently, these evolving populations, by acquiring mutations that were beneficial under several environmental conditions, expanded the niche they could potentially realize.

And then there are old cells that acquire dangerous mutations and give rise to cancer.

When an individual family member acquires enough random mutations, it breaks away to form a new family.

As some randomly acquire additional mutations, they grow even more.

If both copies acquire mutations, it is possible that a subfunctional event occurs.

The process of DNA replication inherently places cells at risk of acquiring mutations.

Dispersed repetitive elements, on the other hand, are more challenging to identify, due to the fact that they are longer and have often acquired mutations.

Do tumors start off lethal or do they grow into lethality, acquiring mutations over time that enable them to kill?

The idea was that as tumors grow, they acquire mutations that enable them to spread throughout the body.