Approved research

Using genetic methods to explore etiologic hypotheses of depression

Lay summary

Depression is a serious disorder that can cause mental distress, impair the ability to function in everyday life, and increase the risk for physical diseases like heart disease and diabetes. According to the World Health Organization, depression is the leading cause of disability worldwide. By studying the factors that contribute to this disease, we can help to come up with new ways to prevent and treat depression at a population level. The goal of this project is to use genetic data from the UK biobank to test several theories about the causes of depression. Existing studies have found many factors that are associated with depression, but it is often hard to tell why these associations exist. Because a person's genes stay the same throughout their life, studies using genetic data can help us to explore complicated questions about the causes of depression. The first aim of this project will be to look at the relationship between certain signaling chemicals found in the blood and depression. Studies have previously found that high or low levels of these chemicals are associated with depression. However, many factors associated with depression can influence levels of these chemicals, including sleep and exercise. This aim will explore whether these chemicals are a true causal factor for depression, or whether this association is due to other factors such as health behaviors in people with depression. The second aim of this project will be to look at the relationship between depression and sleep. We know that people with depression often have problems with their sleep, but we do not know why. This aim will look at whether there is overlap between the genes that are associated with depression and the genes that are associated with sleep problems The third aim of this project will be to look at whether depression is a single disorder, or if it is multiple disorders that happen to have similar symptoms. Depression can only be diagnosed by using symptoms reported by the person who has it, but sometimes different diseases can cause similar symptoms. This aim will use genetic and symptom data from the UK biobank to look at whether there are useful ways to identify distinct subgroups of people with depression. It is expected that this project will be completed over a two-year period.