Researchers at Seoul National University Hospital (SNUH) have discovered a biomarker that causes restless legs syndrome (RLS).
RLS is a neurological condition where patients feel a strong urge to move or feel numbness in their legs before falling asleep and occurs in one in 10 adults. According to the hospital, patients suffering from the disease often describe the symptoms as the feeling of crawling insects.
Despite such symptoms, researchers have been unable to find a clear disease mechanism, while many believed that iron deficiency in the brain, inflammatory reactions, and nervous system hypoxia affect the onset of RLS.
In the research to find the exact cause of the disease, the team, led by Professor Jung Ki-young, discovered a major protein that causes RLS. Professor Shin Jung-won at CHA Bundang Hospital also participated in the study.
The team discovered the protein after conducting a proteomic analysis using serum samples from seven RLS patients and six healthy controls. Proteomic analysis is a method of comprehensively studying proteins in vivo, identifying proteins that act on disease, and understanding their interactions.
Through the analysis, the team found eight unique proteins only observed in RLS patients.
Later, the researchers confirmed a link between these and proteins related to iron deficiency and hypoxia. Through this analysis, the team found that a total of four proteins -- C3, C4A, AHSG, A2M -- were the main proteins that act on RLS.
The team expects that the new biomarkers will help diagnose and treat RLA in the future as the hospitals previously had to diagnose the disease based on the patient's explanation and physician's expert judgment.
"By using biomarkers, hospitals can objectively quantify the numerical values and make an accurate diagnosis," the team said. "Also, the biomarkers can help further development of therapeutic drugs."
Professor Jung said, "There were many RLS cases where it was not possible to receive accurate diagnosis or treatment as hospitals had no biomarkers to diagnose the disease."
Jung added that protein analysis using bioinformatics and discovery of biomarkers is a new basis for reducing misdiagnosis of RLS.
Sleep Medicine published the results of the study.