Manganese superoxide dismutase gene Ala-9Val polymorphism might be related to the severity of abnormal involuntary movements in Korean schizophrenic patients

Objective: This study examined whether the manganese superoxide dismutase (MnSOD) gene Ala-9Val single-nucleotide polymorphism (SNP) is associated with neuroleptic-induced tardive dyskinesia (TD) and the severity of the abnormal involuntary movements in Korean schizophrenic patients. Method: We investigated whether the MnSOD gene Ala-9Val SNP is associated with TD in Korean schizophrenic patients with (n = 83) and without (n = 126) TD who were matched for exposure to antipsychotics and other relevant variables. Results: Logistic regression analysis revealed that being older (p = 0.026) was a risk factor for TD, but that there was no significant association between MnSOD gene and TD. Abnormal involuntary movements were more severe in carriers of the Ala allele than in noncarriers (p = 0.044). Conclusion: These findings do not support that the MnSOD gene Ala-9Val SNP is associated with TD in Korean schizophrenic patients. However, this polymorphism might be related to the severity of abnormal involuntary movements in this population.