DOPAMINE D4 RECEPTOR VARIANTS IN CHINESE SPORADIC AND FAMILIAL SCHIZOPHRENICS

Variation in the number of tandem repeats of a 48 base pair (bp) unit was found in the gene of the dopamine D4 receptor (DRD4), The number o f repetitions of the 48bp unit was shown to influence the binding of c lozapine, which suggests that different alleles may function different ly in vivo and affect the pathogenesis of schizophrenia, Genotypes of DRD4 polymorphism were analyzed for 47 schizophrenic probands who had at least one living sibling with a diagnosis of schizophrenia, 35 unaf fected siblings of the schizophrenic proband, 42 sporadic schizophreni c patients, and 43 healthy controls without a family history of psycho sis, There was no significant difference in genotypic or allelic distr ibutions among the four groups, Significant differences in the frequen cies of two- and seven-repeats alleles between the Chinese and Caucasi ans controls were noted. The present study did not support that a part icular allele or genotype of the 48bp-repeat of DRD4 was associated wi th schizophrenia. (C) 1997 Wiley-Liss, Inc.