ABSTRACT
OBJECTIVES: Catechol-O-methyltransferase(COMT) is involved in the degradation of catecholamine neurotransmitters and has been investigated as a candidate gene in schizophrenia. Recently, possible relationship between functional COMT gene polymorphism and schizophrenia has been suggested. To address the possible role of functional COMT gene polymorphism in the predisposition to schizophrenia, we carried out an association study in Korean schizophrenic patients and controls. METHODS: One hundred and three Korean inpatients diagnosed as schizophrenia and 103 age and sex matched controls were selected as study subjects. Patients were subgrouped into two groups on the basis of history of aggressive behavior, family history of schizophrenia and related disorders, and age at onset. We determined COMT genotypes using PCR of the relevant region followed by digestion with NlaIII and electrophoresis. RESULTS: No significant differences of allele and genotype frequencies were noted between patients and controls. However, when patients were categorized by the presence of family history of schizophrenia and related disorders, patients with family history showed almost 4-fold higher frequency of having COMT L allele containing genotype compared to controls(p=0.02, OR=3.9, 95% CI=1.10-14.33). CONCLUSION: Although our results do not support an association between functional polymorphism of COMT gene and schizophrenia overall, the findings suggest an association between functional COMT gene polymorphism and familial schizophrenia. Further studies with large samples are needed to confirm this association.