The Korean Undiagnosed Rare Disease Diagnosis Research Program (K-UDP) targets patients who do not know the cause of their diseases.

Korean Undiagnosed Disease Program

An undiagnosed rare disease is defined as a disease that has not been confirmed by long-term and repeated standard diagnostic tests and treatment. According to the Korea Disease Control and Prevention Agency, it is estimated that the number of undiagnosed rare disease cases in Korea exceeds 400 per year.


Seoul National University Hospital’s Center for Rare Diseases was designated as a center to conduct the ‘Korean Undiagnosed Rare Disease Diagnosis Research Program’ by the Ministry of Health and Welfare and the Center for Disease Control in 2017, based on its research capabilities that led the nation’s first rare disease research team in 2008.

K-UDP targets patients who do not know the cause of their diseases, despite a long diagnostic journey. Based on clinical information, additional tests and ‘family trio genetic tests’ for individual patients (a test based on the family tree of patients and parents) are provided to the patients. The results are interpreted within the center to provide an adequate treatment plan. After the diagnosis is completed, the patient is returned to the regional center for rare diseases in the headquarters or the patient’s area of residency for a long-term follow-up treatment.

Furthermore, through collaboration with various domestic and international research teams utilizing animal experiments, protein structure research, multiomics data, etc., we are continuously making efforts to identify the causes of new diseases that have not been known so far. In the long term, our goal is to develop treatments for rare diseases through the elucidation of the pathophysiology of these conditions.

If diagnosis is difficult even through the current medical knowledge of the program, the accumulated clinical and genomic data will be shared with international research groups. In addition, efforts are being made to develop new treatments by studying the mechanism of occurrence of rare diseases.