HDC and Cognitive impairment: Pathways affected and major proteins present in such pathways include neuroinflammation (HDC, NOTCH, VWF), synapses and synaptic transmission (BSN, EPHB2), cognitive impairment (SLIT2, RYE2, NF1), behavior (PCM1, EPHB2), seizure/epilepsy (KCNQ2, CACNA2D2), blood–brain barrier (HDC and VWF), brain damage (EPHB2, VWF, CACNA2D2), brain cell death (ADNP and CACNA2D2), traumatic brain injury (TBI, RECK and MEGF8), and ion-channels (KCNQ2, CACNA2D2), and autoimmunity (VWF, RECK, SCARF1).