Is it possible that a doctor could send your blood to a lab to check for depression?
New research shows some hope that in the future, lab testing might be used to screen not only for cholesterol and other medical conditions, but also for depression.
Dr. Spijker Sabine, from the Center for Neurogenomics and Cognitive Research at VU University in Amsterdam, and his colleagues, have identified seven genes that might someday be of use in diagnosing depression by laboratory testing. “This is a first, but major step in providing a molecular diagnostic tool for depression,” says Sabine.
Major depressive disorder is a common psychiatric condition that affects nearly 15 million Americans every year — almost seven percent of the population. It is the leading cause of disability, and the most common cause of suicide. There are multiple causes of depression, and many studies have shown a clear genetic component. Depression can at times be difficult to diagnose, as it sometimes presents with physical symptoms such as chronic pain, fatigue, sleep problems, and weight changes, which may appear more prominently than depressed mood.
Sabine and his colleagues enrolled 21 healthy participants and 21 patients diagnosed with major depressive disorder who were not medicated in their study.
The researchers used a technique known as gene expression profiling to look for genes in the depressed patients that differed from genes in the healthy patients. Gene expression profiling is a way in which scientists can look at how genes react differently in the body’s cells. With this technique, scientists can analyze many genes at the same time, and tell how active they are, which might vary depending on genetic differences between individuals.
Sabine and his colleagues drew blood from all the study participants, and applied a substance called lipopolysaccacharide to the blood cells to see if there were genes that responded differently to the chemical. They found seven genes that had significantly different responses between the depressed participants and the healthy participants.
They then repeated the tests on blood samples from another set of participants — 13 patients with depression and 14 healthy subjects — and found that the tests missed only 24.1 percent of the depressed patients, with false positive results in 28.2 percent of the healthy patients.
Although these results at present are not a perfect diagnostic tool, few screening tests are, and this study is an important first step toward further novel lines of research.
Sabine’s results have exciting promise for the potential development of objective screening or confirmatory laboratory testing of a common psychiatric illness. Not only does this study provide further evidence for a biochemical basis of major depressive disorder, but these results could lead to further research into new treatments or even the ability to prevent the development of symptoms.
The study can be found in the July 15th issue of Biological Psychiatry
Source: Biological Psychiatry