Once the GATA4 gene mutation was diagnosed, we realised that no other treatment options were possible in this case, such as switching to sulfonylureas, which has shown benefits in forms of neonatal diabetes characterised by mutations in the transport protein, especially in the most prevalent NDM-causing mutations (KCNJ11 and ABCC8) [21,22,23]. The gene discussed is KCNJ11; the disease is neonatal diabetes mellitus.