Ultraviolet Light DNA Damage

Synonyms

Sunlight damage to DNA; UV damage to DNA

Synopsis

Sunlight is healthy and necessary in vitamin D activation, but it is also a major cause of skin cancer. UV light causes the formation of several DNA adducts, of which the most serious ones are cyclobutane dimers and pyrimidine-pyrimidone (6–4) photoproducts. Skin cancer can be understood in the context of these adducts, and a deficiency in DNA polymerase η, the translesion DNA polymerase that copies past the major adduct, gives rise to a form of the disease xeroderma pigmentosum.

Introduction

Ultraviolet (UV) light is a major issue in human cancer because of skin cancer, which is a very significant problem. Aside from some chemicals that cause skin cancer (e.g., arsenic, which affects the skin in areas not exposed to light), skin cancer can be understood primarily in the context of DNA damage. Further, individuals deficient in certain DNA repair genes – or DNA polymerases required for efficient bypass of DNA damage, e.g., DNA...