Table 1.

Function characterization of epigenetic alterations in IDD in text.

Name	Type	Target	Expression	Functional role	Reference
/	Histone phosphorylation	Chk2	Up	Cell cycle arrest	[92, 93]
H3K27me3	Histone trimethylation	NOX4	Up	Oxidative stress	[94]
PARK2	DNA methylation	Parkin	Up	Mitophagy	[95, 96]
WNT5A	DNA methylation	Wnt-β	Up	Proinflammation	[98]
CARD14	DNA methylation	NF-κB	Up	Proinflammation	[98]
EFHD2	DNA methylation	NF-κB	Up	Proinflammation	[98]
RTKN2	DNA methylation	NF-κB	Up	Proinflammation	[98]
MAPKAPK5	DNA methylation	MAPK	Up	Proinflammation	[98]
PRKCZ	DNA methylation	MAPK	Up	Proinflammation	[98]
miR-21	Noncoding RNA	PDCD4	Down	Proliferation	[100]
miR-146a	Noncoding RNA	TRAF6	Down	ECM degradation	[101]
miR-98	Noncoding RNA	IL-6/STAT3	Down	Inhibition of ECM degeneration and apoptosis	[102]
miR-494	Noncoding RNA	SOX9	Down	ECM degeneration and apoptosis	[103]
miR-132	Noncoding RNA	GDF5	Down	ECM degradation	[104]
SPARC	DNA methylation	SPARC	Down	ECM degradation	[106]