PDX1 and type 2 diabetes mellitus: For both T1D and T2D, there was a decrease in β-cell function pathways (e.g., “regulation of gene expression in β-cells”, “insulin secretion and processing”) and in “maturity-onset diabetes of the young”, which includes many transcription factors (TFs) involved in the maintenance of the β-cell phenotype and function (e.g., PDX1 and PAX6) (Figures 1B, 1C, S1A, and B).