News Releases & Research Results Elucidation of clinical and genetic characteristics of mitochondrial liver disease for the first time in Japanese

The results of research conducted by Dr. Masaru Shimura and Director Kei Murayama of the Department of Metabolism, Center for Medical Genetics, Chiba Children's Hospital; Director Mureo Kasahara of the Organ Transplantation Center, National Center for Child Health and Development; Professor Akira Ohtake of Saitama Medical University; Professor Yasushi Okazaki of Juntendo University School of Medicine; Chief Director Shunsaku Kaji of the Department of Pediatrics, Tsuyama Chuo Hospital; and Director Ayano Inui of the Department of Pediatric Hepatology and Gastroenterology, Saiseikai Yokohama City Tobu Hospital.

• Clinical and genetic characteristics and prognoses were examined in 23 Japanese patients with severe mitochondrial liver disease*.
  *Mitochondrial diseases are caused by an inborn error of metabolism, which impairs energy production, with an incidence of about 1 per 5,000 people. Mitochondrial diseases with neuromuscular symptoms have been investigated in detail. However, their clinical and genetic characteristics, mainly liver symptoms (e.g., infantile jaundice), remain unclear.
• Specifically, the causative gene of severe mitochondrial liver disease was identified in 18 patients (78%). About half of the patients developed growth disorders as initial symptoms in early infancy, while 21 patients (91%) suffered from jaundice/cholestasis in infancy. Liver transplantation was performed in 12 patients, of whom 5 patients survived.
• The results of this research should be useful for early diagnosis of severe mitochondrial liver disease, selection of treatment, and examination of indications.

This program was conducted with the support of the Practical Research Project for Rare/Intractable Diseases by AMED.

The results of this research project were published in the European scientific journal Orphanet Journal of Rare Diseases on July 24.

Shimura M., et al. Clinical and molecular basis of hepatocerebral mitochondrial DNA depletion syndrome in Japan: evaluation of outcomes after liver transplantation Orphanet Journal of Rare Diseases
DOI：10.1186/s13023-020-01441-5