XPC (DNA repair protein complementing XP-C cells) protein is a pivotal DNA damage recognition factor that plays an indispensable role in the global-genome nucleotide excision repair (GG-NER) pathway. As the primary initiator of GG-NER, it acts as a universal sensor for a wide array of helix-distorting DNA lesions, including those induced by ultraviolet (UV) radiation and chemical carcinogens. Upon binding to damaged DNA, the XPC complex orchestrates the recruitment of the entire repair machinery, serving as a critical guardian of genomic integrity. The calculated molecular weight of XPC is about 106 kDa, but due to post-translational modifications, about 120 kDa will be observed.