TCERG1L hypermethylation is a risk factor of diabetic retinopathy in Chinese children with type 1 diabetes
Authors:   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China; Shanghai Eye Diseases Prevention &amp; Treatment Center, Shanghai Eye Hospital, Shanghai 200040, China; National Clinical Research Center for Eye Diseases, Shanghai 200080, China, Qian Yu , Lin Qiu-Rong ,   Shanghai Eye Diseases Prevention &amp; Treatment Center, Shanghai Eye Hospital, Shanghai 200040, China, Xiang Zhao-Yu ,   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China, Cui Li-Pu ,   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China, Sun Jia-Qi ,   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China, Li Si-Cong ,   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China, Qin Xin-Ran ,   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China, Zou Hai-Dong ,   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China; Shanghai Eye Diseases Prevention &amp; Treatment Center, Shanghai 200080, China, Yang Chen-Hao ,   Department of Ophthalmology, Children&#x2019;s Hospital of Fudan University, Shanghai 201102, China, Jin Pei-Yao ,   Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai First People&#x2019;s Hospital, Shanghai 200080, China; Shanghai 200040, China; National Clinical Research Center for Eye Diseases, Shanghai 200080, China
Published: February 2024

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.P<0.05), and 328 of these were identified with a significance of Adj.P<0.01. Among these, 319 CpG sites were hypermethylated and 432 were hypometh­ylated in the case group relative to the controls. Pyrosequencing revealed that the transcription elongation regulator 1 like (TCERG1L, cg07684215) gene was hypermethylated in the four T1DM children with DR (P=0.018), which was consistent with the result from the first survey. The methylation status of the other three DMS (cg26389052, cg25192647, and cg05413694) showed no difference (all P>0.05) 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.