Congenital adrenal hypoplasia is a designated intractable disease that lacks corticosteroids that are important for maintaining vital activity, and the number of patients in Japan is estimated to be about 1,000.About 30% of patients had an unknown cause.

　The research team found an abnormality in the gene SAMD24 in 11 patients by DNA analysis of 9 patients with congenital adrenal hypoplasia of unknown cause. In addition to adrenal abnormalities, the clinical symptoms of 11 patients had common hematopoietic abnormalities, susceptibility to infection, failure to thrive, gonadal symptoms, and gastrointestinal symptoms, and were found to be unknown genetic disorders.The name of the disease, named after the acronym for symptoms, was proposed as "MIRAGE syndrome".

　This time, it was found that cell proliferation was strongly suppressed by artificially working the abnormal SAMD9 gene using cultured cells.Analysis of patient cells to elucidate the mechanism revealed that the SAMD9 gene abnormality caused an abnormality in the endosomal system, which is one of the intracellular substance transport mechanisms, resulting in poor cell condition.Such a disease is unparalleled, and it was found that MIRAGE syndrome is a new disease in terms of clinical, genetic and mechanical aspects.It should be noted that 9 out of 11 people with the SAMD2 gene abnormality develop myelodysplastic syndrome, which is extremely rare in children, and that the deletion of chromosome 9 in which the abnormal SAMD7 gene is present was involved. ..

　The findings obtained in this study will be useful in the development of treatments for MIRAGE syndrome, and will also be applied to the development of new treatments for partial symptoms (congenital hypoplasia of the adrenal plaque, myelodysplastic syndrome, etc.) caused by MIRAGE syndrome. It is expected.