NEIL1 and Parkinson disease: For example, an altered expression and activity of OGG1 has been observed in head and neck cancers [34,35], of NTH1 in gastric cancer [36], and of NEIL3 in various human cancers [37,38], whereas a loss of NEIL1 causes memory and brain defects indicative of early-onset neurodegenerative disease, similar to those observed in Alzheimer’s and Parkinson’s diseases [39,40].