Answer:
Mutations on DNA that can lead to skin cancer and other skin problems
Explanation:
A Pyrimidine dimer is a molecular lesion that causes mutations that can lead to melanomas and skin sensitivity. It is caused by a photochemical reaction after the exposition of DNA to ultraviolet light.
These mutations happen on thymines or cytosines and can be repaired by a photolyase, an enzyme that adhere the dimers.
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