Next, we looked at the relevant distance in gene expression between (i) the scRNA-seq dataset from all human β-cells (healthy and T1D, 8,349) and (ii) the expression of UPR signature genes (GO:0030968)29 and β-cell-specific gene markers (INS, PAX6, NKX2.2, NKX6.1, MAFA, and PDX1). This evidence concerns the gene NKX2-2 and type 1 diabetes mellitus.