Using engineered short fragments of tau (K19 or K12) or a mixture of tau fragments (K19 + τ306, K18 + K19) as substrates, specific detection of the prion-like tau seeding activities by RT-QuIC assays had been reported with autopsy brain tissues of AD, Pick’s disease, and chronic traumatic encephalopathy (Saijo et al., 2017; Kraus et al., 2019; Metrick et al., 2020). Here, KRT19 is linked to Alzheimer disease.