HPGDS and Alzheimer disease: While Omega class GSTs have been found to be highly expressed in some tumours, and have been proposed as an anti-cancer drug target, other studies have implicated Omega GSTs as determinants of the age at onset of Alzheimer’s disease and have suggested a pro- inflammatory role for GSTO1-1 in Toll-like receptor 4 (TLR4) linked inflammation2–6.