Genome-wide DNA methylation analysis related to ALS patient progression and survival.

Abstract

Epigenetics contributes to the pathogenesis of amyotrophic lateral sclerosis (ALS). We aimed to characterize the DNA methylation profiles associated with clinical heterogeneity in disease progression and survival among patients. We included a cohort of 41 patients with sporadic ALS, with a median follow-up of 86.9months, and 27 rigorously matched healthy controls. Blood-based genome-wide DNA methylation analysis was conducted. A total of 948 progression rate-associated differentially methylated positions, 298 progression rate-associated differentially methylated regions (R-DMRs), 590 survival time-associated DMPs, and 197 survival time-associated DMRs (S-DMRs) were identified, using complementary grouping strategies. Enrichment analysis of differentially methylated genes highlighted the involvement of synapses and axons in ALS progression and survival. Clinical analysis revealed a positive correlation between the average methylation levels of the R-DMR in PRDM8 and disease progression rate (r = 0.479, p = 0.002). Conversely, there was an inverse correlation between the average methylation levels of the R-DMR in ANKRD33 and disease progression rate (r = -0.476, p = 0.002). In addition, patients with higher methylation levels within the S-DMR of ZNF696 experienced longer survival (p = 0.016), while those with elevated methylation levels in the S-DMR of RAI1 had shorter survival (p = 0.006). DNA methylation holds promise as a potential biomarker for tracking disease progression and predicting survival outcome and also offers targets for precision medicine.