ABSTRACT
OBJECTIVE: Attention-deficit hyperactivity disorder is a highly heritable psychiatric condition of early childhood onset characterized by marked inattention, hyperactivity and impulsiveness. Genes involved in catecholamine pathways, including catechol-O-methyltransferase (COMT), represent potential candidates, given that around 70% of children with ADHD show a symptomatic improvement when treated with methylphenidate, a psychostimulant. This study was designed to investigate the association of COMT polymorphism with ADHD in Korean population. METHOD: In this study, we used both family-based (the haplotype relative risk & the haplotype-based haplotype relative risk design) and case-control approaches to examine COMT polymorphism. The sample included 31 Korean children (25 males, 6 females) diagnosed as ADHD by DSM-IV, their 31 families with 31 mothers and 27 fathers and 106 normal controls. RESULTS: There were no differences of COMT genotype and allele frequencies between ADHD patients and control subjects. Also, there was no difference of COMT genotype between ADHD patients and HRR controls. The COMT1 allele frequencies of normal control group in Korean population (75%) was significantly different with that frequency of Caucasian population (50%). CONCLUSION: These results suggest that COMT polymorphism is not associated with ADHD in Korean population. However, the possibility of interacting effects of COMT with other genes or environment should be investigated.
Subject(s)
Child , Humans , Male , Attention Deficit Disorder with Hyperactivity , Case-Control Studies , Catechol O-Methyltransferase , Diagnostic and Statistical Manual of Mental Disorders , Fathers , Gene Frequency , Genotype , Haplotypes , Methylphenidate , MothersABSTRACT
OBJECTIVES: This study was carried out to investigate the clinical availability of topographic auditory event related potential P300 as a biological marker in children with attention deficit hyperactivity disorder(ADHD). METHODS: The subjects were composed of children with ADHD(n=22:16 boys, 6 girl s:mean age=89.8+/-17.1months) and normal controls(n=20:12 boys, 8 girls:mean age=90.6+/-16.8months). Topographic auditory event related potential was measured by "oddball paradigm", and the latencies and amplitudes of P300 of both groups were determined by Global Field Power Measurement. After 8 weeks treatment with methylphenidate, P300 of ADHD children were also measured. RESULTS: Both P300 latency and amplitude were not different between ADHD children after treatment and normal controls, but significantly different between ADHD children before treatment and normal controls, and between before and after treatment of ADHD children. CONCLUSIONS: The results implicate that the latency and amplitude of P300 may be considered as state markers of ADHD.