“…BDNF is widely expressed in the hippocampus and cerebral cortex (Hofer, Pagliusi, Hohn, Leibrock, & Barde, 1990; Huang & Reichardt, 2001) and enhances hippocampal long-term potentiation (Figurov, Pozzo-Miller, Olafsson, Wang, & Lu, 1996) associated with both memory and learning efficiency (Hariri et al, 2003; Yamada, Mizuno, & Nabeshima, 2002). The gene encoding BDNF contains a functional single-nucleotide polymorphism (SNP) resulting in a valine (val) to methionine (met) substitution at amino acid 66 ( Val66Met , rs6265) in the 5ʹ pro-BDNF domain (Egan et al, 2003).…”