The TGF-β2/ATX ratio could be used to differentiate between control and glaucoma groups (P = 0.0036), POAG and SOAG groups (P = 0.0284), POAG and XFG groups (P = 0.0027), and SOAG and XFG groups (P = 0.039). The gene discussed is ENPP2; the disease is glaucoma.