Korean Children With

The authors examined the association between the MspI C/G and DraI C/T genotypes of the a2A-adrenergic receptor gene and white-matter connectivity and attentional performance before and after medication in 53 children with attention-deficit hyperactivity disorder. Subjects who carried the T allele at the DraI polymorphism showed fewer changes in the mean commission error scores after 8 weeks of medication and decreased fractional anisotropy (FA) values in the right middle frontal cortex than subjects without the T allele. Subjects with the C allele at the MspI polymorphism showed decreased FA values in the right postcentral gyrus than subjects without. (The Journal of Neuropsychiatry and Clinical Neurosciences 2013; 25:222–228) A ttention-deficit hyperactivity disorder (ADHD) isa disorder primarily characterized by inatten-tion, impulsivity, and hyperactivity, with a prevalence of 5.3%.1 It has an estimated heritability of approxi-mately 76 % and is thought to be a complex, polygenic disorder.