Austrian scientists have come up with a new blood test they say could be the first to detect depression.
Researchers at the MedUni Vienna said the test picks up a protein in cells — known as SERT (short for serotonin transporter) — that regulates the brain chemical serotonin, which is sometimes called the "happiness hormone" because it is involved in mood.
Many antidepressants work by targeting SERT to boost levels of serotonin — a lack of which can cause depressive symptoms.
The new study used functional magnetic resonance imaging of the brain to determine a close relationship between the speed of serotonin uptake in blood cells and depression.
"This is the first study that has been able to predict the activity of a major depression network in the brain using a blood test," said lead researcher Lukas Pezawas, with the University Department of Psychiatry and Psychotherapy at MedUni Vienna.
"While blood tests for mentall illnesses have until recently been regarded as impossible, this study clearly shows that a blood test is possible in principle for diagnosing depression and could become reality in the not too distant future."
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