Consistently, hybridization chain reaction fluorescence in situ hybridization (HCR-FISH) detects CASP8-GGGAGAEXP transcript staining in the hippocampus from CASP8-GGGAGAEXP (+) and polyGR+ AD autopsy brains but not AD brains that are positive for polyGR+ aggregates and negative for the CASP8-GGGAGAEXP (Fig. S27). Here, CASP8 is linked to Alzheimer disease.