Indeed, epidemiological data show that patients receiving olanzapine incur an approximately 10-times higher risk of diabetic ketoacidosis than the general population (Polcwiartek et al., 2016), suggesting the possibility that olanzapine directly impairs the function of pancreatic β cells, the exclusive source of insulin, in a speculated few percent of medicated patients (Nagamine, 2014; Nagamine, 2018). The gene discussed is INS; the disease is diabetic ketoacidosis.