Abstract：
DNA methylation plays an important role in the occurrence and development of age-related cataracts (ARC). This study aims to reveal potential epigenetic biomarkers of ARC by detecting modifications to the DNA methylation patterns of genes shown to be related to ARC by transcriptomics. The MethylationEPIC BeadChip (850 K) was used to analyze the DNA methylation levels in ARC patients and unaffected controls, and the Pearson correlation test was used to perform genome-wide integration analysis of DNA methylation and transcriptome data. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were used to perform functional analysis of the whole genome, promoter regions (TSS1500/TSS200), and the associated differentially methylated genes (DMG). Pyrosequencing was used to verify the methylation levels of the selected genes. The results showed that, compared with the control group, a total of 52,705 differentially methylated sites were detected in the ARC group, of which 13,858 were hypermethylated and 38,847 were hypomethylated. GO and KEGG analyses identified functions related to the cell membrane, the calcium signaling pathway, and their possible molecular mechanisms. Then, 57 DMGs with negative promoter methylation correlations were screened by association analysis. Pyrosequencing verified that the ARC group had higher methylation levels of C3 and CCKAR and lower methylation levels of NLRP3, LEFTY1, and GPR35 compared with the control group. In summary, our study reveals the whole-genome DNA methylation patterns and gene expression profiles in ARC, and the molecular markers of methylation identified herein may aid in the prevention, diagnosis, treatment, and prognosis of ARC.
摘要：
DNA甲基化在年龄相关性白内障（ARC）的发生和发展中起重要作用。这项研究旨在通过检测转录组学显示与ARC相关的基因的DNA甲基化模式的修饰来揭示ARC的潜在表观遗传生物标志物。MethylationEPICBeadChip（850K）用于分析ARC患者和未受影响的对照组的DNA甲基化水平，采用Pearson相关性检验对DNA甲基化和转录组数据进行全基因组整合分析。基因本体论（GO）和京都基因和基因组百科全书（KEGG）数据库用于执行全基因组的功能分析，启动子区（TSS1500/TSS200），和相关的差异甲基化基因（DMG）。焦磷酸测序用于验证所选基因的甲基化水平。结果表明,与对照组相比，在ARC组中共检测到52,705个差异甲基化位点，其中13,858例高甲基化，38,847例低甲基化。GO和KEGG分析确定了与细胞膜相关的功能，钙信号通路，以及它们可能的分子机制。然后，通过关联分析筛选出57个启动子甲基化负相关的DMGs。焦磷酸测序证实，与对照组相比，ARC组C3和CCKAR甲基化水平较高，NLRP3、LEFTY1和GPR35甲基化水平较低。总之,我们的研究揭示了ARC的全基因组DNA甲基化模式和基因表达谱，本文鉴定的甲基化分子标志物可能有助于预防，诊断,治疗,和ARC的预后。
