Metagenomic sequencing of brain tissue from Alzheimer's disease patients and controls

The goal of this study was to investigate the potential presence and influence on pathology of microbial DNA in post-mortem human brain tissue from Alzheimer's disease (AD) patients, patients with mild cognitive impairment (MCI), high pathology non-demented controls (HPC), and normal non-demented controls. DNA was extracted from frozen brain tissue from two brain regions, the superior frontal gyrus (SFG) and the inferior temporal gyrus (ITG). After DNA extraction, the majority of methylated human DNA was removed with a kit. The remaining human mitochondrial DNA and microbial DNA were sequenced using 16S rRNA gene sequencing technologies.