Transcriptome study of Alzheimer's disease on post-mortem human brain

INTRODUCTION: Neuropsychiatric symptoms are common in people with Alzheimer’s disease (AD) across all severity stages. Their heterogeneous presentation and variable temporal association with cognitive decline suggest shared and distinct biological mechanisms. We hypothesized that specific patterns of gene expression associate with distinct NIMH Research Domain Criteria (RDoC) domains in AD. METHODS: Post-mortem bulk RNAseq on the insula and anterior cingulate cortex from 60 brain donors representing the spectrum of canonical AD neuropathology combined with natural language processing approaches based on the RDoC Clinical Domains. RESULTS: Distinct sets of >100 genes (pFDR<0.05) were specifically associated with at least one clinical domain (Cognitive, Social, Negative, Positive, Arousal). In addition, dysregulation of immune response pathways was shared across domains and brain regions. DISCUSSION: Our findings provide evidence for distinct transcriptional profiles associated with RDoC domains suggesting that each dimension is characterized by specific sets of genes providing insight into the underlying mechanisms. We performed RNA sequencing of two brain regions (BA16 and BA32) from both AD patients and controls, and performed dimensional regression analysis of gene expression profiles over different RDoC scores.