Researchers Identify Mutations in Genes that Are Linked to Suicidal Behavior

A team of researchers from Mount Sinai Hospital and Columbia Universityhave identified several mutations in a series of genes that are involved in suicidal behavior.

Co-author Mercedes Pérez-Rodríguez, a researcher at Mount Sinai, and the team aimed “to identify a model able to differentiate between people with and without a background of suicide attempts.” They focused on a range of 840 functional single nucleotide polymorphisms (SNPs) that are present in 312 genes expressed in the brain. When the team analyzed the SNPs of men who had been diagnosed with a psychiatric illness, they were correctly able to identify “69% of patients by using an algorithm based on three SNPs from three different genes.”

The genes in the current study, which code the 5-HT1E serotonin receptor (HTR1E, SNP rs10944288), the pi subunit of the A gamma-aminobutyric acid receptor (GABRP, SNP hCV8953491), and the alpha-2-actinin (ACTN2, SNP rs707216) subunit of the ionotropic glutamate receptor channel, were examined on a very limited basis in previous studies.

In recent years, research has started to use genetics as a way to analyze the causes of suicidal behavior, focusing on parameters related to serotonin function, such as 5-hydroxyindoleacetic acid (5-HIAA) of the cerebrospinal fluid (CSF) or measurements of the hypothalamic-pituitary-adrenal axis (HPA) such as the dexamethasone suppression test, but these models have been of no clinical use, according to the researchers.

"The predictive features of this algorithm for estimating suicide risk outperform those of all other models developed to date,” the researchers said, adding that the new model identified three neurobiological systems that could be involved in an organic predisposition (diathesis) to suicidal behavior.

The team hopes that the current results may be used in future studies “to create simple genetic tests of use in diagnosing and identifying patients prone to attempting suicide.”