The clinical function of ERCC3 is clearly known to be associated with inherited disease including UV-hypersensitive NER syndromes xeroderma pigmentosum (XP), Cockayne Syndrome (CS), combined XP and CS (XP/CS), and trichothiodystrophy (TTD) [39–42]. This evidence concerns the gene ERCC3 and xeroderma pigmentosum.