Combination of Risk Alleles in NTRK2 Tied to Suicide Attempt
Depressed patients carrying three most significant risk markers at much higher suicide risk
WEDNESDAY, April 7 (HealthDay News) -- A combination of several independent risk alleles within the neurotrophic receptor-encoding gene NTRK2 may be associated with suicide attempts among depressed patients, according to research published in the April issue of the Archives of General Psychiatry.
Martin A. Kohli, Ph.D., of the Max Planck Institute of Psychiatry in Munich, Germany, and colleagues investigated genetic variations in the brain-derived neurotrophic factor (BDNF) gene and its high-affinity receptor gene, receptor tyrosine kinase 2 (NTRK2). They collected blood or saliva samples from 394 depressed patients, 113 of whom had attempted suicide, and 366 matched healthy controls. They also conducted two replication studies, with 744 German patients with major depressive disorder and 921 African-American non-psychiatric clinic patients, of whom 152 and 119, respectively, had previous history of suicide attempt.
The researchers found an association between single nucleotide polymorphisms in NTRK2 and suicide attempt in all three groups. Patients carrying genotypes with the three most significant risk markers had a 4.5-fold higher risk for suicide attempt than depressed patients carrying non-risk genotypes.
"Our results suggest that a combination of several independent risk alleles within the NTRK2 locus is associated with suicide attempt in depressed patients, further supporting a role of neurotrophins in the pathophysiology of suicide," the authors write.
Several authors have financial ties to pharmaceutical companies and/or have invented products related to the diagnosis or treatment of depression or predisposition to suicide.