Mitochondrial trifunctional protein deficiency due to HADHB gene mutation in a Chinese family

• Main Authors: Xiaona Fu, Feixia Zheng, Yao Zhang, Xinhua Bao, Shuang Wang, Yanling Yang, Hui Xiong
• Format: Article
• Language: English
• Published: Elsevier 2015-12-01
• Series: Molecular Genetics and Metabolism Reports
• Subjects: Mitochondrial trifunctional protein (MTP) deficiency; HADHB gene; Peripheral neuropathy; Fatty acid oxidation
• Online Access: http://www.sciencedirect.com/science/article/pii/S2214426915300501

We report an 8-year-old girl with lower limb weakness since birth in whom mitochondrial trifunctional protein (MTP) deficiency, an autosomal recessive fatty acid oxidation disorder caused by HADHA or HADHB mutations, had not been definitively diagnosed before she was referred to our hospital. Repeated blood acylcarnitine analysis revealed slightly increased long-chain 3-OH-acylcarnitine levels; electromyography (EMG) suggested peripheral nerve injury; muscle biopsy confirmed a neurogenic lesion in muscle fibers, as shown by EMG. Analysis of the HADHB, which encodes long-chain 3-ketoacyl-CoA thiolase, one of the enzymes constituting mitochondrial trifunctional protein, identified homozygous missense mutation c.739C > T (p.R247C). Mitochondrial trifunctional protein deficiency is an extremely rare disorder and has not been reported in Chinese people to date. It is likely that neonatal onset, as seen in our patient, has not been reported for the neuromyopathic phenotype of mitochondrial trifunctional protein deficiency.