Six patients of Group 2 carried a pathogenic or likely pathogenic variant in KCNJ11 (3 variants), ABCC8 (1 variant) and PDX1 (biallelic variants); a patient with transient neonatal diabetes mellitus had 6q24 methylation defects (Table 1; Online resource 1, left panel). This evidence concerns the gene PDX1 and neonatal diabetes mellitus.