Many DNA repair genes and their polymorphisms including the Xeroderma pigmentosum complementation group D (XPD, also known as Excision Repair Cross-complementation group 2 [ERCC2]), and the X-ray cross-complementing group 1 (XRCC1) have been reported to be associated with several different diseases including glaucoma, which have been shown to be dependent upon the genetics and ethnicity of the individuals or environmental factors [5]. The gene discussed is ERCC2; the disease is glaucoma.