Table 1.

The role of DNA methylation in the pathogenesis of diabetic retinopathy

Refs	Study type	DNA methylation
Diabetes Metab [9]	Clinical study (serum)	Global DNA methylation↑
BMC Med [10]	Clinical study (blood)	DNA methylation↓ in PDR, differential DNA methylation of 28 CpG sites in 17 genes (AHRR, GIPR, GLRA1, and BCOR)
Invest Ophthalmol Vis Sci [11]	Invitro/animal (STZ diabetic mice) Retina	DNA methylation of polymerase gamma (POLG1) gene ↑
Lab Invest [13] Diabetes [12]	Invitro/animal (STZ diabetic mice) Retina	Dnmt1 binding to Matrix metalloproteinase -9 promoter→MMP↑→5mC↓
Invest Ophthalmol Vis Sci [14]	Invitro/animal study (Bovine retinal endothelial)	mtDNA methylation↑