title: Genetic polymorphisms in dopamine- and serotonin-related genes and treatment responses to risperidone and perospirone.
abstract: We investigated the possible association between genetic polymorphisms in the dopamine receptor and serotonin transporter genes and the responses of schizophrenic patients treated with either risperidone or perospirone. The subjects comprised 27 patients with schizophrenia who were clinically evaluated both before and after treatment. The genotyping of the polymorphisms of the dopamine D2 receptor gene (DRD2) (rs1801028 and rs6277), the dopamine D4 receptor gene (DRD4) (120-bp tandem repeats and rs1800955), and serotonin transporter gene (5HTT)(variable number of tandem repeats; VNTR) were performed using the real-time polymerase chain reaction and sequencing. In DRD2 and 5HTT-VNTR, there were no significant correlations between clinical response and polymorphism in the case of risperidone, and for perospirone treatment it was impossible to analyze the clinical evaluation due to the absence of genotype information. On the other hand, in DRD4 there were significant correlations in the two-factor interaction effect on the Positive and Negative Syndrome Scale (PANSS) between the two drugs [120-bp tandem repeat, p=0.003; rs1800955, p=0.043]. Although the small sample represents a serious limitation, these results suggest that variants in DRD4 are a predictor of whether treatment will be more effective with risperidone or with perospirone in individual patients.
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tsutsumi
authors.forename: Tetsufumi
authors.initials: T
authors.lastname: Kanazawa
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kikuyama
authors.forename: Gaku
authors.initials: G
authors.lastname: Okugawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Uenishi
authors.forename: Toshio
authors.initials: T
authors.lastname: Miyamoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Matsumoto
authors.forename: Jun
authors.initials: J
authors.lastname: Koh
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Shinosaki
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Kishimoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoneda
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Kinoshita