O. Ohmori et al., Genetic association analysis between CYP2D6*2 allele and tardive dyskinesia in schizophrenic patients, PSYCHIAT R, 87(2-3), 1999, pp. 239-244
Previous studies have shown a possible association between tardive dyskines
ia (TD) and debrisoquine 4-hydroxylase (CYP2D6) polymorphisms, which result
in absent enzyme activity. We have recently found a positive association b
etween TD and the CYP2D6*10 allele, which codes for the intermediate metabo
lizer (IM) phenotype and is characterized by decreased but not absent CYP2D
6 activity in Japanese schizophrenic patients. In addition, the CYP2D6*2 al
lele with the HhaI site mutation in exon 6 has also been reported to be an
IM allele and a risk factor for Parkinson's disease (PD) in the Japanese po
pulation. In the present study, we investigated potential contributions of
the CYP2D6*2 allele to TD using case-control and regression analysis in 99
schizophrenic patients. No significant differences in genotypic and allelic
frequencies were found between patients with and without TD. Even after us
ing regression analysis to adjust for the confounding variables, there was
no significant association of the CYP2D6*2 genotype with either outcome var
iable, the occurrence of TD or the total AIMS score. These results suggest
that the CYP2D6*2 allele may not contribute to the pathogenesis of TD. (C)
1999 Elsevier Science Ireland Ltd. All rights reserved.