This observation was further corroborated by the observed association between P-181 tau and hippocampal atrophy and a near significant correlation between T-tau and hippocampal atrophy in A.H.T. users, and agrees with results of earlier studies reporting a correlation between T-tau and P-181 tau; and hippocampal atrophy (46, 47). The gene discussed is MAPT; the disease is hippocampal atrophy.