Keywords: CS, Cockayne syndrome; ERCC5; ERCC5, Excision Repair Cross-complementing Rodent Repair Deficiency Complementation Group 5 gene; Excision Repair Cross-complementing Rodent Repair Deficiency Complementation Group 5 gene; NER, Nucleotide excision repair; UV, Ultraviolet; WES, Whole exome sequencing; XP, Xeroderma pigmentosum; XP-G, Xeroderma pigmentosum complementation group G; nucleotide excision repair; whole exome sequencing; xeroderma pigmentosum complementation group G.