Gutierrez, J. C.; Chen, Y.; Babaian, A.; Dhindsa, R. S.; Lareau, C. A.

Mounting evidence implicates herpesvirus reactivation in the etiology of Alzheimer's disease, yet we lack a refined molecular characterization of pathogenesis in neurodegeneration. Here, we mine over 10 petabytes of human sequencing data for viral transcripts, identifying recurrent herpes simplex virus 1 (HSV-1) reactivation in healthy but not pathological post-mortem human brain tissue. Integrative single-nucleus analyses resolve direct evidence of HSV-1 expression in RORB+ glutamatergic neurons, implicating viral reactivation in a neuronal population progressively lost during dementia.