Pre-clinical studies examining sex differences in murine models of Alzheimer’s disease: ↓ means decreased, ↑ means increased, NOR: novel object recognition, BACE1: beta-site amyloid precursor protein cleaving enzyme, MWM: morris water maze, WT: wild-type, PnMS: pre-natal maternal stress, TTR: transthyretin, eIF2α: eukarytoic inititation factor 2 alpha, and NFT: neurofibrillary tangles. The gene discussed is TTR; the disease is Alzheimer disease.