In addition, several significantly changed genes at this timepoint play roles in the maintenance of critical brain barriers including the blood–brain barrier (CYP7B1, MERTK, CD44) and synapse maintenance in neuronal networks (MERTK, RELN), and associate with neurodegenerative disease pathogenesis in early stages prior to protein accumulation. Here, CYP7B1 is linked to neurodegenerative disease.