Pattern of variation in DNA methylation during pregnancy among mothers who delivered preterm in the GARBH-Ini cohort

Background: DNA methylation (DNAm) may play an important role in birth outcomes. Material and Methods: Genome wide DNAm was analysed in peripheral blood DNA of women at multiple time points during gestation. A novel empirical method was used to identify CpG sites with high temporal variance in methylation associating with preterm birth. Results: High variability at 1296 CpG sites from the promoter regions of 1197 genes significantly associated with PTB. These genes belonged to pathways involved in signalling by platelet derived growth factor, platelet homeostasis, collagen degradation, extracellular matrix and circadian clock. Conclusions: The findings provide novel information which might help in development of predictive biomarkers of preterm birth outcome.