Atypical depression has been linked to genetic factors.

The data from the systematic review has been published in the journal Clinical Neuropsychiatry, which is in the first quartile of Scopus indexing.

Depression is an extremely debilitating condition affecting up to 310 million people worldwide. There are various types of this disorder, one of which is atypical depression. It is distinguished from the classic "melancholic" type by the presence of increased appetite, weight gain, and mood swings in patients, rather than insomnia and weight loss. Additionally, individuals with atypical depression may experience leaden paralysis (heaviness in the arms and legs), drowsiness, and heightened sensitivity. Those suffering from this condition are at a higher risk for cardiovascular diseases, potentially linked to increased appetite and cravings for carbohydrates.

It is already known that genetic factors play a significant role in the development of depression as a whole. However, the data on atypical depression has been fragmented, making it difficult to draw conclusions about patients' genetic predisposition to this illness. “High-quality, persuasive evidence is needed to subsequently identify genetic markers of this disorder, indicating that a person has atypical depression rather than another condition, including other types of mental disorders or metabolic issues,” noted Beatrice Volel. “At the Psychosomatic Medicine Clinic of Sechenov University, we often treat patients with atypical depression and understand that diagnosing it is not straightforward. At the same time, the earlier the diagnosis is made, the more effective the therapy will be.”

Thus, researchers analyzed existing studies concerning genetic factors associated with atypical depression. They found that the genetic polymorphisms identified in individuals with this disorder are related to the serotonin transporter gene, endocrine regulation, immune response, as well as cellular regulation, particularly genes associated with body fat and obesity-related proteins. Furthermore, “the results confirm that atypical major depressive disorder is inherited to a certain extent,” the study states.

The scientists hope that this information will enable the identification of genetic markers indicating the risk of developing atypical depression, which would allow for more accurate diagnoses and effective treatments, as well as prevention of the disorder's development.

At Sechenov University, the search for such markers has already begun, said Dmitry Petelin, assistant at the Department of Psychiatry and Psychosomatics at Sechenov University and psychiatrist at the Psychosomatic Medicine Clinic: “We are conducting our own research – collecting blood samples from our patients and performing genetic analyses to identify the relationship between specific genes and the disease. We plan to obtain the first results within a few years.”