The molecular mechanisms that underlie islet dysfunction in Type 1 (autoimmune) and Type 2 diabetes are not fully understood, and genetic risk factors are of limited clinical and predictive value. Epigenetic modifications to histones or DNA provide a potential readout of environmental influence from sources such as diet and the microbiome. DNA methylation is an epigenetic modification of cytosine residues that alters DNA accessibility and downstream gene expression patterns. Whole genome bisulphite sequencing (WGBS) is a technique that interrogates such genome-wide DNA methylation patterns. Treatment with sodium bisulfite converts unmethylated cytosine residues to uracil, which then appear as thymine bases after sequencing; thus, this technique allows for identification of methylated and unmethylated DNA with single base pair resolution. WGBS can be used to identify differentially methylated regions between samples from non-diabetic and diabetic pancreatic tissue.