Demirbilek H, Cayir A, Flanagan SE, et al. - Among patients with PTF1A enhancer mutations, phenotype and genotype features were examined and findings of long-term follow-up were analyzed in this study, given biallelic mutations in the PTF1A enhancer represent the most common reason for isolated pancreatic agenesis. Participants were 30 patients with diabetes due to PTF1A enhancer mutations. These were observed for a median span of 4 years. Experts discovered five different homozygous mutations impacting conserved nucleotides in the PTF1A distal enhancer. The Chr10:g.23508437A>G mutation (n = 18) was reported to be the most common one. Most of the patients presented with diabetes soon following birth. In this cohort, the reported transiently raised ferritin concentration, anemia, and cholestasis were the previously undescribed common characteristics. In this largest report of patients with diabetes caused by PTF1A enhancer mutations, the observations expand the disease phenotype, recognizing recurrent extrapancreatic characteristics which possibly reflect long-term intestinal malabsorption.