GSTT1 encodes a glutathione S-transferase enzyme that catalyzes conjugation of reduced glutathione to exogenous and endogenous hydrophobic electrophiles, including 1,2-epoxy-3-(4-nitrophenoxy)propane and phenethylisothiocyanate, while displaying glutathione peroxidase activity with cumene hydroperoxide. The enzyme functions primarily in cellular oxidant detoxification within the cytosol 1. GSTT1 operates through glutathione-dependent biotransformation of carcinogens, xenobiotics, and oxygen free radicals 2, with significant inter-individual variability due to common null polymorphisms (gene deletions). Disease relevance is substantial: GSTT1 null genotype carriers show increased esophageal cancer susceptibility, particularly in Asian populations (OR=1.233) 1, and hepatocellular carcinoma risk in Chinese populations (OR=1.53) 3. Conversely, GSTT1 null alleles demonstrated protective effects against human papillomavirus infection 4. In multiple sclerosis, GSTT1 null genotypes combined with GSTM1 deletions increased disease risk 6.8-fold, suggesting compromised antioxidant defense in neuroinflammatory conditions 5. Recent evidence indicates GSTT1 enhances osteogenic differentiation of adipose-derived stem cells through modulation of antioxidant capacity and metabolic pathways relevant to bone regeneration 6. Clinically, GSTT1 polymorphism status may predict cancer susceptibility and stem cell therapeutic potential, while GSTT1 null genotype frequencies vary significantly across ethnic populations 7.