CLOZAPINE RESPONSE AND THE 5HT(2C)CYS(23)SER POLYMORPHISM

THE, presence of the 5HT(2C) receptor allele, Ser(23), has recently be en reported to predict favorable response to the antipsychotic drug, c lozapine. This finding is of interest as Ser(23), compared with the mo re abundant Cys(23), alters pharmacological characteristics of the rec eptor and therefore may provide insights into the mechanism of action of antipsychotic drugs. We determined 5HT(2C) receptor genotype at the Cys(23)Ser locus in 66 subjects participating in double-blind studies of clozapine. There was no relationship between Ser(23) and clozapine response (p = 0.30, Fisher's exact) nor was there any effect of Ser(2 3) upon absolute levels of psychiatric symptoms after 10 weeks of cloz apine treatment (t = -0.57, p = 0.57). These data suggest that this 5H T(2C) receptor polymorphism is not associated with clozapine response.