NER-associated diseases are characterized by sun (UV) hypersensitivity and include xeroderma pigmentosum (XP), UV-sensitivity syndrome (UVSS), Cockayne syndrome (CS), cerebro-oculo-facio-skeletal (COFS) syndrome, XPF-ERCC1 (XFE) progeroid syndrome, trichothiodystrophy (TTD) and disorders that combine the symptoms of these syndromes, including XP/CS [35]–[39]. Here, ERCC1 is linked to Cowden syndrome 1.