Mitochondrial Membrane Protein-Associated Neurodegenerative Disease Caused By C19orf12 Gene Mutation:A Case Report And Literature Review

ObjectiveTo report a case of mitochondrial membrane protein-associated neurodegene-rative disease（Mitochondrial membrane protein-associated neuropathy,MPAN）caused by C19orf12 gene mutation,and to explore the clinical features、the mutation characteristics of the pathogenic gene、Diagnosis,differential diagnosis and treatment of MPAN in combination with literature review.The purpose of this study is to improve the understanding and diagnosis and treatment of MPAN among clinicians.Methods1.A retrospective analysis of the clinical manifestations、imaging features、mutation sites of the pathogenic gene,、diagnosis、treatments and follow-up results of a case of MPAN diagnosed by gene were in our hospital.2.Manually searched from 1993 to March 2019 with keywords such as “brain tissue iron deposition neurodegenerative diseases,mitochondrial membrane proteinrelated neurodegenerative diseases,neurodegeneration with brain iron accumulation,Mitochondrial membrane protein-associated neuropathy,C19orf12” Inter-CNKI,Wanfang database,Pubmed database database,collect literature on MPAN with more complete case data for analysis.Results1、For the first time in China,a case of MPAN caused by mutation of C19orf12 gene was reported.The main clinical manifestations were abnormal mental behavior,decreased cognitive function,and Parkinson’s disease-like symptoms.Magnetic Resonance Imaging（MRI）suggested:（1）Mild brain atrophy changes;（2）Abnormally low signal in bilateral basal ganglia,C19orf12 gene carries two missense mutations: c.172G>A（p.G58R）;c.260G>C（p.R87T）,the drug treatment with dopamine and reduce dystonia was poor,but the symptoms were not controlled.2、Searching the literatures of MPAN in the domestic and foreign databases,it was found that there were 30 studies with complete case data describing 118 patients,the average age of onset was about 11.5 years old,and the incidence rate of clinicalrare and specific cases was unknown.The most common clinical manifestations were superior motor neuron damage（84%）,cognitive dysfunction（59%）and dystonia（55%）.Visual impairment,mental disorder,lower motor neuron involvement and Parkinson’s disease-like symptoms were also possible.Most of the patients showed iron deposition in globus pallidus and substantia nigra,and the whole brain atrophy occurred in late stage.There were 38 mutation sites in C19orf12 gene,including mutation site c.204₂14del11（p.Gly69ArgfsX10）.C.32 C > T（p.Thr11Met）was the most common.The mutation locus c.260 G > C（p.R87T）was not reported in this patient.At present,there is no effective treatment.Conclusion1.It is very important to understand the clinical and imaging features of MPAN.2.The detection of C19orf12 gene is a reliable method for the diagnosis and pathogenicity of mutation sites in patients with MPAN.