Table 1.

Subtypes of lncRNA introduced according to the recent studies.

Name	Length (nt)	Function	Example	References
Intergenic	828	Control the expression of both near and remote genes	LINC00152, H19, IPW, MEG3	[35–37]
Intragenic	—	Attach to promoters and enhancers	RUNXOR	[35, 39]
Enhancer	—	Specific enhancer–promoter looping, gene expression	IG-DMR eRNAs	[35, 56]
Antisense	—	Gene regulation, X-inactivation, imprinting, and epigenetic regulation	KCNQ1OT1, AIRN, NESPAS, Ube3a-ATS, ANRIL	[42–44]
sno-lncRNAs	—	Contribute in the pathogenesis of PWS	—	[42–44]
circRNAs	Under 100 nt to over 4 kb	Related with disease phenotype	cANRIL	[42–45]
ciRNAs	—	Gene transcription	—	[42–45]

lncRNAs: long noncoding RNAs; LINC00152: long intergenic non-protein-coding RNA152; IPW: imprinted gene in the Prader-Willi syndrome region; MEG3: maternally expressed gene 3; RUNXOR: RUNX1 overlapping RNA; IG-DMR: intergenic differentially methylated region; KCNQ1OT1: KCNQ1 opposite strand/antisense transcript 1; AIRN: antisense of insulin-like growth factor-2 receptor RNA noncoding; UBE3A-ATS: UBE3A antisense transcript; ANRIL: antisense noncoding RNA in the INK4 locus.