Mice lacking Ndufs4, encoding NADH: ubiquinone oxidoreductase iron-sulfur protein 4 (NDUFS4) recapitulates the main findings of complex I (cI)-related LS, including severe multisystemic cI deficiency and progressive neurodegeneration. The gene discussed is NDUFS4; the disease is hyperinsulinemic hypoglycemia, familial, 4.