Finally, we also observed that canonical pathways (CPs), which were specific to brain functionality such as synaptic long term potentiation and neurotransmitter signalling pathways, or described as altered in PD such as mitochondrial dysfunction, oxidative phosphorylation and axonal guidance associated pathways were significantly represented (p-value < 0.05) in both types of BTIs (Fig. 4b). Here, CAD is linked to Parkinson disease.