Per Pathoma: early inherited cases of Alzheimer's dementia are associated with mutations in presenilin-1/presenilin-2, as well as Down's syndrome. Down's would be due to an extra chromosome 21, which carries the gene for amyloid precursor protein (APP). Extra APP is converted to A-beta amyloid and this forms extracellular neuritic plaques, a prominent feature of Alzehimer's.

Important to not confuse Amyloid A protein (one of the answer choices) with Amyloid precursor protein. Deposition of AA amyloid is more associated with chronic inflammatory states, malignancy, and Familial Mediterranean Fever. Beta-2 microglobulin is another amyloid association: dialysis-associated (deposits in joints)

Amyloid A : seen in chronic inflammatory conditions, deposition of amyloid in tissues

B2 microglobulin: associated with ESRD and long term dialysis

Neurofilament protein: Form the cytoskeleton of neurons (in healthy individuals)

Presenilin: associated with familial alzheimers disease

Presenilin... think "PREmature SENILE" for early-onset Alzheimer’s