Table 1. Retrotransposons reported as dysregulated in brain, cerebrospinal fluid (CSF) or plasma from patients with neurodegenerative disorders.

A comprehensive summary of the retrotransposons identified in human neurodegenerative diseases, including retrotransposon subtype. Font in blue: transposable element-derived transcripts and protein detected in human brain tissue, grey: transposable element-derived transcripts detected in human cerebral spinal fluid, and red: transposable element activity detected in human serum. Refer to references for full details of each study indicated.

Disease	Increased		Decreased
	Transposable Element	Subfamily	Transposable Element	Subfamily
Alzheimer’s Disease (AD)	ERV	ERV17, ERV9, ERVH48I, ERVK22I, ERVKC4, ERVL [11] ERVFc_1 [46]
	LINE1	L1PA7_5 [11] L1MB4_5 [46]
	LTR	LTR12C, LTR14 [11] LTR77, PRIMA4_LTR [46]
	SINE	AluYh9, AluYc5, AluSp [46]	SINE	AluYa5, AluYb8, AluYc1, AluYi6 [10]
	Other	SVA_B, SVA_C, TIGGER2 [11] THER2, PB1D11 [46]
Progressive Supranuclear Palsy (PSP)	ERV	ERV17, ERV9, ERVH48I, ERVK22I, ERVKC4, ERVL, ERVH, ERVP71A_I [11]
	LINE1	L1PB2c [11]
	LTR	LTR12C, LTR14 [11]		LTR14A [10]
			SINE	AluYa5, AluYb8, AluYc1, AluYi6, AluSp, AluY, AluYd8, AluYe5, AluYg6, AluYk11, AluYk12 [10]
Amyotrophic Lateral Sclerosis (ALS)	ERV	ERVK pol and RT protein [30] ERV-K gag, pol, env transcripts and env protein [18]
	LINE1	L1MA9 [40]
	LTR	LTR2, LTR70, MER21B, MER51C [40]
	SINE	AluYk12, AluYa5, FRAM [40]
	Other	Reverse transcriptase activity [27–29]
Frontotemporal lobar degeneration (FTD)	LINE1	L1MA9 [40]
	LTR	LTR2, LTR70, MER21B, MER51C [40]
	SINE	AluYk12, AluYa5, FRAM [40]
Sporadic Creutzfeldt-Jakob Disease (sCJD)	ERV	ERV-W, ERV-T, ERV-FRD, ERV- L, ERV-9 [56]