Manganese superoxide dismutase gene polymorphism and schizophrenia: Relation to tardive dyskinesia

There has been increasing evidence that deranged superoxide dismutase (SOD) activities might be a risk factor for schizophrenia and/or tardive dyskine sia (TD). In the present study, we investiogated the genetic association be tween a functional polymorphism (Ala-9Val) in the human manganese (Mn) SOD gene and schizophrenia or TD (192 schizophrenics : 39 with TD and 153 witho ut TD; 141 controls). No significant differences in the allelic or genotypi c distribution between schizophrenics and controls were observed. However, we did find a significant difference in genotypic distribution between schi zophrenics with and those without TD (p = .03). Moreover, decreased -9Ala ( mutant) allele was found among patients with TD (p = .02; odds ratio = 0.29 ; 95% confidence interval = 0.10-0.83). In conjunction with previous findin gs of increased free radicals and decreased SOD activities in TD subjects, these results suggest that the -9Ala (high activity) MnSOD allele may play a role in protecting against susceptibility to TD in schizophrenics. (C) 20 00 American College of Neuropsychopharmacology. Published by Elsevier Scien ce Inc. All rights reserved.