The catechol-O-methyltransferase gene (COMT) plays a crucial role in the metabolism of catecholamines in the frontal cortex. A single nucleotide polymorphism (Val(158)Met SNP, rs4680) leads to either methionine (Met) or valine (Val) at codon 158, resulting in a three- to fourfold reduction in COMT activity. The aim of the present study was to assess the COMT Val(158)Met SNP as a risk factor for attention-deficit/hyperactivity disorder (ADHD), ADHD symptom severity and co-morbid conduct disorder (CD) in 166 children with ADHD.
View Article and Find Full Text PDFA functional polymorphism (His452Tyr) in the gene encoding the serotonin 2A receptor (HTR2A) has been previously associated with human episodic memory performance and with differences in brain volume in memory-related brain regions. Here we present data obtained through imputation and fine-mapping showing that multiple loci within HTR2A are significantly associated with human memory performance independently of the His452Tyr polymorphism. Our data support the existence of multiple memory-related loci within HTR2A.
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