The Met allele of BDNF Val66Met polymorphism is associated with increased BDNF levels in generalized anxiety disorder.

Background: Generalized anxiety disorder (GAD) is a common psychiatric disorder characterized by long-term worry, tension, nervousness, fidgeting, and symptoms of autonomic system hyperactivity. The neurobiology of this disorder is still unclear, although it has been shown consistently that the environment and the genetic profile could increase its risk. We examined whether a polymorphism in the brain-derived neurotrophic factor (BDNF) gene, which plays a role in neuroplasticity and memory, could increase the vulnerability to this disorder.