Ultraviolet (UV) radiation is mutagenic.

How do UV-induced DNA lesions lead to mutation?

Key Concepts

UV Radiation and DNA Damage

Ultraviolet (UV) radiation can cause direct damage to DNA by inducing the formation of pyrimidine dimers, primarily thymine dimers. These dimers distort the DNA helix, leading to replication errors if not repaired. Understanding this mechanism is crucial for grasping how UV exposure can lead to mutations.

DNA Repair Mechanisms

Cells have evolved several DNA repair mechanisms, such as nucleotide excision repair (NER), to correct UV-induced lesions. NER recognizes and removes damaged sections of DNA, allowing for accurate repair. If these repair processes fail or are overwhelmed, the unrepaired lesions can result in permanent mutations.

Mutation and Its Consequences

A mutation is a change in the DNA sequence that can alter gene function and potentially lead to various outcomes, including cancer. UV-induced mutations often occur in critical genes that regulate cell growth and division, making it essential to understand how these mutations can contribute to tumorigenesis and other genetic disorders.