Srijan Sen, MD PhD
“Improving our knowledge about the biology of depression will help people understand and accept that this is a real illness, encourage them to talk about it with friends and family, and to seek appropriate treatment."
A desire to understand the intricacies of human behavior and the wide variation in how people may respond to similar situations led Srijan Sen, M.D., Ph.D., to the field of psychiatry. Now specializing in genetic research, Sen investigates ways to harness the rich information contained in the human genome to help develop better screening methods and accelerate the development of more effective and personalized treatments for those living with depression.
“Our ability to do genetic research has expanded dramatically in the last 10 years. Technology in genomics and the Human Genome Project have made it far more feasible to understand the genetic basis that underlies depression,” Sen says.
Sen explains that recent advances in genetic research can benefit medicine in enormous ways, and for people living with depression in particular, by identifying genetic factors that may predict who could be at increased risk of depression so that those individuals could be earlier and more carefully screened; by helping us understand the genetic basis for treatment response, allowing better matches between individual profiles and prescribed treatments; and by helping science develop more effective and personalized treatments for depression than are currently available.
One of Sen’s major projects involves following first-year physicians over the course of the (very pressure-filled) intern year as a model for examining the relationship between stress and depression. “It’s a stressful time for many reasons,” Sen explains, since interns face long work hours and sleep deprivation and often confront intense emotional situations. The stress of internship is often uncontrollable and chronic, and many physicians consider internship one of the most stressful years of their lives. This makes the intern year an ideal period over which to examine how stress may be involved in the onset of depression.
At the beginning of the year, medical interns have roughly the same rate of depression as the general population. But as the year progresses, about half will have an episode of depression – a dramatic spike. Sen’s team is tracking genetic factors and other biomarkers in groups of interns at the beginning and end of the stressful 12 months of internship to see which of those factors, when combined with the impact of stress, may be implicated in the onset of a depressive episode. Their findings will further help determine which genetic profiles might be more at risk. Read more about this research here.
Sen’s recent study on a “depression gene” garnered a great deal of attention because it helped validate earlier seminal work by U-M researchers which found evidence that genetic factors are involved in vulnerability to depression under stress. The study, a summary analysis of findings from a broad range of relevant studies, confirmed a link between a gene that regulates the neurotransmitter serotonin and an individual’s ability to recover from serious trauma, such that under stress, people with the gene had a higher rate of depression compared to people without the gene who also underwent similar stress.
“This is the first real concrete association between a specific genetic factor and depression,” Sen says. “In the next few years we will surely find more and more genes that are involved, understand the biology underlying depression, and, ultimately, over the long term, develop better treatments.”