The p.Gly436Val variant (87% residual activity) was detected in a patient with succinic semialdehyde dehydrogenase (SSADH) deficiency (Struys et al., 2006), and the novel variant, p.Leu453Phe (68% residual activity), was found in a patient diagnosed with D‐2‐HGA Type II. The gene discussed is ALDH5A1; the disease is hyperinsulinemic hypoglycemia, familial, 4.