High-resolution whole-genome DNA methylation revealed unique signatures of painful diabetic neuropathy

This work describes the DNA methylation signature and identifies genes associated with neuropathic pain in type 2 diabetes mellitus. Genome-wide methylation data for 315 DNA (WB) samples were generated using Illumina Infinium Methylation EPIC v1.0 BeadChip. Four different selection criteria were used to identify promising pain-related genes. The findings revealed significant differences in methylation patterns between painful and painless diabetic neuropathy and identified a set of individual CpG sites of unique candidate genes associated with the painful phenotype. Several of these genes, including GCH1, MYT1L and MED16, have been previously linked to pain-related phenotypes or diabetes. Through pathway enrichment analysis, we demonstrated that specific epigenetic signatures could contribute to the complex phenotype of diabetic neuropathy and cluster analyses highlighted significant epigenetic dissimilarities between painful and painless phenotypes. Our results uncovered epigenetic differences between painful and painless diabetic neuropathy patients and identified targeted genes linked to neuropathic pain through DNA methylation mechanisms. This approach holds promise for investigating other chronic pain conditions, such as secondary chronic pain from cancer treatment, thoracic surgery, and various transplant settings. Bisulphite converted DNA isolated from 315 whole blood samples were hybridised to the Illumina Infiniun MethylationEPIC BeadChip following manufacture's protocols.