An Association Study of Schizophrenics and Their Clinical Variables with Tryptophan Hydroxylase Gene Polymorphism / 신경정신의학

OBJECTIVES: The genetic polymorphism of tryptophan hydroxylase (TPH) the rate-limiting enzyme in the biosynthesis of serotonin, has been to be related with various psychiatric disorders such as bipolar disorders. However, the role of TPH gene polymorphism in schizophrenia is totally unknown. Author examined the association of the TPH gene polymorphism with the development and the clinical variables of schizophrnia. METHODS: Genomic DNAs from 217 schizophrenic patients and 236 healthy controls were isolated, and TPH gene was amplified using PCR. Amplified TPH DNA was digested with NheI and the polymorphism was examined by electrophoresis on agarose gel. RESULTS: The allele frequencies and the genotypes of TPH gene were not significantly different between the schizophrenics and the control groups. They were also not associated with most of the clinical variables of schizophrenia such as subtypes, suicidal ideation, age at onset, and family histories. Among the clinical variables, only suicidal rate was highly correlated with genotype 218C/C. CONCLUSION: We found possible association of the suicical behavior with 218C/C polymorphism. However, it seems that A218C polymorphism of TPH gene does not associated with the development and other clinical variables of schizophrenia.

Cognitive Function and Its Clinical Significance in Schizophrenic Patients / 신경정신의학

OBJECTIVES: This study was designed to evaluate the cognitive function in schizophrenic pathents. We also examined the correlation of cognitive imparirment with other clinical variables. METHODS: A total of 25 partients and 19 normal controls completed Vienna Test System, a computerized neuropsychological test. These included Cognitrons test, continuous attention test, standard progressive matrices. We separately assessed the patient group on the positive and Negative Syndrome Scale(PANSS) and Extrapyramidal Symptom Rating Scale(EPS scale). The other clinical variables included in this study were age, sex, education level, disease duration, clinical subtype, medication state and genetic factor. RESULTS: Schizophrenic patients had poorer performance than normal controls on the tests of cognitrone, continous attention, and stand progressive matirces, independent of sex, genetic factors, EPS scale scores, PANSS scores, disease duration. The cognitive impairment in schizophrenics was mainly associated with their education levels and clinical subtypes. CONCLUSION: Inlight of our results, it seemd that some schizophrenics perform poorly on cognitive tsasks, and this poor performance may be associated with education levels and clinical subtypes. The more careful evaluation of cognitive function in schizophrenic patients would be needed for their proper management.