ERCC4 and neoplasm: The ERCC family contains 4 core tumor-associated genes (ERCC2, ERCC3, ERCC4, ERCC5) and the XPD protein encoded by ERCC2 serves as the helicase subunit of the transcription factor IIH (TFIIH) complex, which is required for DNA damage verification.[7,8] ERCC2 functions as a regulator of the nucleotide excision repair (NER) pathway, which is responsible for repairing bulky DNA lesions induced by environmental mutagens, UV irradiation, and certain chemotherapeutic agents.