Mitochondrial ND1 mutations and HSP60 and HSP70 mRNA expressions in patients with schizophrenia

Mitochondrial dysfunction originating from genetic alterations may play a role in mental illnesses. This study was designed to investigate mitochondrial ND1 mutations associated with schizophrenia and reveal the mRNA expression levels of HSP60 and HSP70. ND1 mutations in 40 patients with schizophrenia were detected by Sanger sequencing. HSP60 and HSP70 mRNA expression levels of patients and healthy controls were evaluated by real-time PCR. Gene expression analysis was conducted using the 2^−∆∆Ct method. The ND1 mutation frequency was 19/40 among the patients. Frequencies of T4216C (n = 8) and A3480G (n = 4) were higher than other mutations. HSP60 expression was higher (p = 0.0145), while HSP70 expression was lower (p = 0.0254) in patients than healthy controls. Carriers of ND1 mutations had lower levels of HSP60 and HSP70 expression than patients who did not carry those mutations (p = 0.1270 and p = 0.6451, respectively). Patients with schizophrenia carrying divergent ND1 mutations showed different expression patterns of HSP60 and HSP70 (p = 0.0434 and p = 0.0969, respectively). In conclusion, patients with schizophrenia had a high frequency of ND1 mutations. Identifying ND1 mutations and analyzing expression levels of HSP60 and HSP70 may contribute to discovering potential molecular markers for diagnosing schizophrenia.