Dominant pattern of Inheritance of MNGIE’s disease.


Topic:

Ultra-Rare myopathies and dystrophies (<1:100,000 worldwide)

Poster Number: 204

Author(s):

Shri Kant Mishra, Robert Freundlich, MD, Shaweta Khosa, MD

Institutions:

1. Olive View-UCLA Medical Center, 2. Olive View UCLA Medical Center, Sylmar, 3. UCLA Oliveview

Objective: To describe a case of MNGIE disease with autosomal dominant pattern of inheritance in a Hispanic family. Background: Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare genetic disorder characterized by gastrointestinal dysmotility, external ophthalmoplegia, mitochondrial myopathy, peripheral neuropathy and leukoencephalopathy. It is caused by mutation in the thymidine phosphorylase (TYMP) gene and usually inherited as an autosomal recessive pattern. Design/method: We report a Hispanic family with genetically proven MNGIE disease affecting members in two generations including three out of four siblings, their mother, maternal uncle and maternal aunt, no consanguinity. Results: Six family members in two generations were affected. Our patient, two of his siblings and their mother were among the affected members. MNGIE was also reported in maternal aunts and uncles. Among the affected family members, the oldest brother passed away at 24 years of age, mother at age 46 and maternal uncle at age 48 years. However, no symptoms were reported in the father or paternal family members. Although the inheritance pattern of MNGIE is reported to be autosomal recessive, we observed an unusual autosomal dominant pattern of inheritance in this family. We postulated that severe TYMP dysfunction resulted in de novo mitochondrial mutations in germinal cells of the mother. The eldest offspring was spared due to younger age of mother at the time of pregnancy. Conclusions: We report first family with MNGIE disease with autosomal dominant inheritance. Currently stem cell therapies are being investigated for treatment of this disease. We are currently working on starting a clinical trial at our site to study stem cell therapy in patients with MNGIE syndrome.