Scientists have discovered a previously unrecognized genetic mechanism behind major depression.
The finding may guide future therapeutic strategies for this debilitating mood disorder.
Major depression is a psychiatric disorder that is responsible for a substantial loss in work productivity and can even lead to suicide in some individuals.
"Current treatments for major depression are indispensable but their clinical efficacy is still unsatisfactory, as reflected by high rates of treatment resistance and side effects," said study author Martin A. Kohli from the Max Planck Institute of Psychiatry in Munich, Germany.
"Identification of mechanisms causing depression is pertinent for discovery of better antidepressants," he said.
Kohli and colleagues performed a stringent genome-wide association study of patients diagnosed with major depression and matched control subjects with no history of psychiatric illness.
They identified SLC6A15, a gene that codes for a neuronal amino acid transporter protein, as a novel susceptibility gene for major depression.
The finding was confirmed in an expanded study examining over 15,000 individuals.
The finding is published in the current issue of the journal Neuron.