TCERG1L hypermethylation is a risk factor of diabetic retinopathy in Chinese children with type 1 diabetes

AIM: To identify the differential methylation sites (DMS) and their according genes associated with diabetic retinopathy (DR) development in type 1 diabetes (T1DM) children. METHODS: This study consists of two surveys. A total of 40 T1DM children was included in the first survey. Because no participant has DR, retina thinning was used as a surrogate indicator for DR. The lowest 25% participants with the thinnest macular retinal thickness were included into the case group, and the others were controls. The DNA methylation status was assessed by the Illumina methylation 850K array BeadChip assay, and compared between the case and control groups. Four DMS with a potential role in diabetes were identified. The second survey included 27 T1DM children, among which four had DR. The methylation patterns of the four DMS identified by 850K were compared between participants with and without DR by pyrosequencing. RESULTS: In the first survey, the 850K array revealed 751 sites significantly and differentially methylated in the case group comparing with the controls (|Δβ|>0.1 and Adj.P0.05) between participants with and without DR. CONCLUSION: The hypermethylation of the TCERG1L gene is a risk factor for DR development in Chinese children with T1DM.