Objectives: Catechol-O-methyltransferase (COMT) plays an important role in metabolizing catecholamines,
including dopamine. Also, several single-nucleotide polymorphisms (SNPs) of the
COMT gene are associated with schizophrenia. Therefore, this study aimed to find the association
between COMT gene SNPs and schizophrenia in Koreans.
Methods: Participants were 366 schizophrenia patients and 359 normal controls. To identify the
SNPs, we performed genetic analyses in 4 SNP regions, via SNP-ITTM assays. We compared allele,
genotype, and haplotype frequencies between the two groups. Moreover, we built subgroups,
based on onset age, and compared individual allele and genotype frequencies among these subgroups.
Results: In female patients, genotype frequencies showed a significant difference in rs2020917
among the 4 SNPs (p=0.0224), but haplotype frequencies showed no such difference among the
4 SNPs between patients and controls. We noted a significant difference in rs1544325 allele frequencies
according to onset age. Also, in female patients, rs1544325 allele and genotype frequencies
varied significantly according to onset age.
Conclusion: This study found no genetic association between the COMT gene’ s 4 SNPs and
schizophrenia in Koreans. However, our findings suggest genetic components for sex-specificity
and onset age in Korean schizophrenics.