Association of the rs1439050 polymorphism and differential expression of NTRK2 gene in the cerebral prefrontal cortex of suicidal individuals from a population in northern Mexico

This study was performed in order to determine whether suicidal behavior is associated with the single-nucleotide polymorphism rs1439050 of the NTRK2 gene and/or with changes in the expression levels of this gene in cases of suicide compared with a control group in a Mexican population.Genotyping of the rs1439050 polymorphism of the NTRK2 gene of individuals who committed suicide (n = 99) and individuals who died for reasons other than suicide (n = 88) was conducted by qPCR.Similarly, using specific qRT-PCR probes, the expression of the NTRK2 gene was assessed in the prefrontal cortex of 20 suicidal cases and 20 control subjects.A significantly higher proportion (p = 0.005) of heterozygous GT genetic frequency was found for the suicidals (64%) than for controls (44%).Importantly, the relative expression levels of NTRK2 were significantly lower (p = 0.035) in suicidal subjects than in control persons.In summary, the heterozygous GT genotype represents a risk factor for suicide under the over-dominant inheritance model.Additionally, alterations in the expression level of NTRK2 in the prefrontal cortex of suicidal subjects were found in the population of study.