In PiD hippocampal sections with dense 3R-tau positive Pick bodies and no 4R-tau staining, GT-38 was negative and in CBD and PSP hippocampal regions with 4R-tau predominant astrocytic and neuronal pathology without 3R-tau inclusions, GT-38 staining was negative (Fig. 2c). Here, MAPT is linked to red-green color blindness.