Ultraviolet-B and Ultraviolet-A II photons (UVB/UVA II photons)

UVB/UVA II photons" refer to *types of ultraviolet (UV) radiation* rather than to a molecule, receptor, or protein. **UVB photons** cover wavelengths 290–320 nm and are strongly absorbed by the epidermal DNA, causing direct DNA damage, sunburn, and genetic mutations that increase cancer risk and also stimulate vitamin D production. **UVA II photons** (320–340 nm) penetrate deeper into the skin, reaching the dermis, causing indirect DNA and structural damage through the generation of reactive oxygen species—leading to photoaging, collagen breakdown, and contributing to skin cancer via indirect mechanisms including oxidative stress and immunosuppression. Neither UVB nor UVA II functions as a receptor, enzyme, or typical drug target; rather, they are forms of electromagnetic radiation that interact with molecular chromophores in cells and tissues. "UVB/UVA II photons" is thus not a *therapeutic target* in the conventional sense, and is not typically represented in drug discovery databases as a modifiable target or molecule. The target name is technically incorrect for purposes of molecular target annotation.

Other names

Ultraviolet B photonsUVBUltraviolet A II photonsUVA II