Several of the commonly downregulated genes in the HNF1A+/H126D endocrine progenitors and HNF1A+/T260M islets are involved in insulin secretion, glucose metabolism and MODY (Figs. S5a–d), suggesting that the downregulation of genes may be involved in the pathogenesis of MODY3 caused by HNF1A mutations located in the DNA-binding domain. This evidence concerns the gene HNF1A and maturity-onset diabetes of the young type 3.