BDNF and COMT polymorphisms

Recent investigations in several species have suggested a role for brain-derived neurotrophic factor (BDNF) in memory, which may be mediated by the influence of BDNF on neuronal plasticity in the hippocampus. BDNF polymorphisms have also been associated with mood disorders. Catechol-O-methyltransferase (COMT) metabolizes dopamine and has been implicated in prefrontal function, another area of the brain relevant for memory. In a sample of 63 young adults with a history of childhood-onset mood disorder, we typed three BDNF polymorphisms, including the BDNF Val66Met single nucleotide polymorphism (SNP), and the COMT Val108/158Met SNP. Multivariate analysis of variance was used to test the association between BDNF and COMT markers and measures of declarative memory. Variants at the three BDNF markers and one COMT marker were not associated with declarative memory function—p-values ranged from 0.25 to 0.98. Higher IQ (F=6.18, df=4, 58, p=0.0003) and female gender (F=4.41, df=4, 58, p=0.0035) were associated with more optimal performance on the memory tasks. This study did not provide evidence supporting an association between BDNF and COMT genes and declarative memory phenotypes.