Final answer:
Mutations in germline cells can be passed on to offspring, affecting every cell, while somatic mutations can lead to cancers such as pancreatic, colon, and colorectal when repair mechanisms fail.
Step-by-step explanation:
The types of cells most damaged by mutations are germline and somatic cells. Whereas germline mutations occur in gametes and can be passed to offspring, affecting every cell of the offspring, somatic mutations occur in other cells of the body and may lead to cancer if many mutations accumulate.
Mutations in repair genes have been associated with several forms of cancer, including pancreatic, colon, and colorectal cancers. The damage is particularly severe when the mutation impedes the cell's ability to repair DNA, leading to uncontrolled cell division, or when a mutation is passed on to the next generation, as seen in diseases like hemophilia and xeroderma pigmentosa.
Cells have multiple mechanisms to repair DNA and correct mutations before they can exert harmful effects. However, if the DNA damage is permanent and irreparable, the affected cell is often prevented from dividing, stopping the propagation of the mutation.