Explanation of Terminology

Hospitals involved in IRUD are classified into three types: IRUD Clinical Centers, Semi-clinical Centers, and Cooperative Hospitals. As of October 2025, there are 535 such hospitals across Japan.

If your family hospital is not an IRUD-affiliated hospital, show your doctor the IRUD brochure(in Japanese) and ask if you can be referred to an IRUD-affiliated hospital.

Go to the list of IRUD-affiliated hospitals　＞
(in Japanese)

As of October 2025, there are 53 hospitals with an IRUD Diagnostic Board.(40 IRUD Clinical Centers and 13 Semi-clinical Centers.)

Go to the list of IRUD Clinical Centers　＞
(in Japanese)

The IRUD Diagnostic Board is made up of doctors and genetic counselors from a wide range of specialties. Led by clinical geneticists, the committee holds regular meetings to review and discuss difficult cases.

The committee also works closely with family doctors and local medical associations to share information throughout each region.

Genes are often called the “blueprints” of the individual. In IRUD, we use advanced analysis technology to examine the all your genes at once.

This may help us find the cause of your condition, especially when standard medical tests have not led to a diagnosis.

At present, we perform whole exome sequencing (WES), which analyzes all DNA regions (exons) that contain information for making proteins.(WES: whole exome sequencing)

In IRUD, we promote information sharing among specialists through our Clinical Specialty Subgroup and IRUD Exchange.

- Clinical Specialty Subgroup

We maintain IRUD Clinical Specialty Subgroup comprised of disease experts. They discuss difficult cases in detail, and when needed, examine patients directly at participating IRUD Clinical Centers.

- IRUD Exchange

Many patients who eventually reach IRUD have spent a long time without a clear diagnosis. In such cases, the condition may be a very rare disease with only a few patients worldwide. To find other patients with the same condition, it is important to search for information not only within Japan but also around the world.
IRUD Exchange is a platform that uses de-identified patient information shared across national borders. Through IRUD Exchange, we hope to gain new clues for diagnoses and for understanding the causes of rare and undiagnosed diseases.

The Initiative on Rare and Undiagnosed Diseases (IRUD), supported by the Japan Agency for Medical Research and Development (AMED), promotes global data sharing　＞