MPG (N-methylpurine DNA glycosylase) is a base excision repair enzyme that catalyzes hydrolysis of deoxyribose N-glycosidic bonds to excise alkylation-induced DNA lesions, specifically 3-methyladenine and 7-methylguanine from damaged DNA. The enzyme functions in both mitochondrial and nuclear compartments through its alkylbase DNA N-glycosylase activity, initiating the repair of DNA alkylation damage and depurination lesions. MPG expression is regulated by a TATA-less, GC-rich promoter containing alternative first exons that generate multiple mRNA isoforms 1. The gene shows dynamic regulation in pathological contexts: MPG gene amplification and expression are significantly increased in high-risk HPV-infected cervical neoplasias, with altered intracellular localization patterns in invasive carcinomas, suggesting involvement in viral carcinogenesis 2. Additionally, MPG polymorphism (rs2858056) and elevated serum MPG protein levels are associated with rheumatoid arthritis susceptibility in Han Chinese populations 3, indicating a broader role in disease pathogenesis beyond DNA repair. These findings suggest MPG functions not only as a housekeeping DNA repair enzyme but also as a regulated component in inflammatory and neoplastic disease processes.