Table 1.

SYNJ1 in human Alzheimer’s disease: genetic association, neuropathology and expression in human brains.

Populations	Genetic Association of SYNJ1	Human Brains
	-	Neuropathology	SYNJ1 RNA	SYNJ1 Protein
Late Onset AD (LOAD)	Not detected [42–46]	Accumulation in plaque-associated dystrophic neurites, in Hirano bodies and in some neurofibrillary tangles [60] Co-precipitation with (PHF)-tau [60]	Transcriptomics: decreased in LOAD (AD Knowledge Portal) [55–57] Increased in LOAD, correlate with levels of phosphorylated tau [60]	Proteomics: increased [58] or decreased (AD Knowledge Portal) [59] in LOAD Increased in detergent-insoluble fraction in LOAD, correlate with levels of phosphorylated tau [60] Decreased in total homogenate and detergent-soluble fraction in LOAD [60, 62]. Within the LOAD cohort, APOE4 carriers have higher SYNJ1 levels than non-carriers [60]
			Increased [64] or unchanged [60] in APOE4 carriers in a control cohort	Increased in APOE4 carriers in a control cohort [64]
			Increased in APOE4 carriers with early LOAD (CDR 0.5–1) [64] and late-stage LOAD (Braak V-VI) [60] miR-195 levels reduced in APOE4 carriers with MCI and early LOAD (CDR 0.5–1), but unchanged in normal aging (CDR 0) or at advanced stages (CDR 3) [69]	Increased in cases with early LOAD (CDR 0.5–1), unchanged at advanced stages (CDR 3) [64]
High Risk Down Syndrome (DS)	Unexplored	Inverse correlation with synaptophysin levels among older individuals with DS-AD [52]	Increased in DS vs. disomic controls [68]	Increased in DS vs. disomic controls [60, 62, 66, 67]
High Risk Autosomal Dominant AD (ADAD)	Yes, early- and late-onset [52]	Co-precipitation with (PHF)-tau [60]	Similar to LOAD (small sample size) [60]	Similar to LOAD (small sample size) [60]

Abbreviations: PHF, paired helical filaments, CDR, clinical dementia rating, miR, microRNA, MCI, mild cognitive impairment.

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