Association of Genetic Variants in the Neurotrophic Receptor-Encoding Gene NTRK2 and a Lifetime History of Suicide Attempts in Depressed Patients

This study determined whether the brain-derived neurotrophic factor (BDNF) gene or its high-affinity receptor gene, receptor tyrosine kinase 2 (NTRK2), confer risk for suicide attempts & major depressive disorder by investigating common genetic variants in these loci. The discovery sample was 394 depressed patients, of whom 113 had attempted suicide, & 366 matched healthy controls. The replication studies comprised 744 German patients with major depressive disorder & 921 African American nonpsychiatric clinic patients, of whom 152 & 119 had attempted suicide, respectively. Results suggest a combination of several independent risk alleles within the NTRK2 locus is associated with suicide attempts in depressed patients, further supporting a role of neurotrophins in the pathophysiology of suicide. (78 refs.) JA