Association between catechol-O-methyltransferase gene polymorphism and attention-deficit hyperactivity disorder in Korean population.

Recently, the relationship between allele frequency distribution and attention-deficit hyperactivity disorder (ADHD) has been actively studied. In Korea, the relationship between the genetic type and alleles for catechol-O-methyltransferase (COMT) gene has been studied in ADHD patients. ADHD was diagnosed in 60 patients according to the Diagnostic and Statistical Manual of Mental Disorders Version IV (DSM-IV) diagnostic criteria and Schedule for Affective Disorders and Schizophrenia for School-Age Children--Present and Lifetime Version (K-SADS-PL), and they were selected for the study. For the control group, normal volunteers were chosen. Blood samples were taken from the 160 subjects. DNA was extracted from blood lymphocytes, and PCR was performed for COMT NlaIII VNTR polymorphism. For the case-control analyses, allele and genotype frequencies were compared using the chi(2) method. When the ADHD group and the normal control group were compared, significant difference was seen on the COMT genetic type, but was not seen on the allele distribution. As a result, it is viewed that there is no relationship between ADHD and the COMT gene, but final decision is indefinite.