A novel GATA6 mutation leading to congenital heart defects and permanent neonatal diabetes: a case report

Permanent neonatal diabetes mellitus is a rare condition mostly due to heterozygous mutations in the KCNJ11, ABCC8 and INS genes. Neonatal diabetes due to pancreatic agenesis is extremely rare. Mutations in PDX1, PTF1A, HNF1B, EIF2AK3, RFX6 and GATA6 genes have been shown to result in pancreatic agenesis or hypoplasia. This report describes a 40-day-old male infant diagnosed with permanent neonatal diabetes associated with atrial septal defect, pulmonary stenosis, patent ductus arteriosus and a novel de novo heterozygous missense mutation (p.N466S) in the GATA6 gene with no evidence of exocrine pancreas insufficiency. In addition to permanent neonatal diabetes, the patient had transient idiopathic neonatal cholestasis and hypoglycaemic episodes unrelated to insulin treatment, features that are rarely described in children with permanent neonatal diabetes.