NDUFA5, as a hydrophobic fraction of the mitochondrial complex I multisubunit enzyme, is believed to be not involved in catalysis, but participated in transferring electrons from NADH to the respiratory chain.22, 23 The expression of NDUFA5 was reduced in brains of autism patients, which might be attributed to mitochondrial dysfunction and impaired ATP synthesis.24 Present study provided evidence that abnormal NDUFA5 expression was involved in the process of fatty liver disease. The gene discussed is NDUFA5; the disease is autism.