Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic disorder that results in an inadequate amount of G6PD enzyme, a biological catalyst that is important to produce the reduced form of nicotinamide adenine dinucleotide phosphate that protects red blood cells against oxidative stress (Luzzatto et al., 2020). Here, G6PD is linked to hyperinsulinemic hypoglycemia, familial, 4.