Importantly, DNA methylation changes were observed in genes associated with type 1 diabetes, including IL32, TRAF3 and DGKQ, and in novel candidate genes, which have not been linked to the disease, such as ARRDC2 and PCBP3. Using pyrosequencing we validated the direction of methylation difference identified by RRBS for eight out of ten selected targets. This evidence concerns the gene ARRDC2 and type 1 diabetes mellitus.