SURF1 deficiency causes demyelinating Charcot-Marie-Tooth disease.

TitleSURF1 deficiency causes demyelinating Charcot-Marie-Tooth disease.
Publication TypeJournal Article
Year of Publication2013
AuthorsEchaniz-Laguna, A, Ghezzi, D, Chassagne, M, Mayençon, M, Padet, S, Melchionda, L, Rouvet, I, Lannes, B, Bozon, D, Latour, P, Zeviani, M, de Camaret, BMousson
JournalNeurology
Volume81
Issue17
Pagination1523-30
Date Published2013 Oct 22
ISSN1526-632X
KeywordsAdult, Age of Onset, Charcot-Marie-Tooth Disease, Child, Preschool, Consanguinity, Female, Homozygote, Humans, Male, Membrane Proteins, Middle Aged, Mitochondrial Proteins, Mutation, Pedigree, Phenotype, RNA Splicing
Abstract

OBJECTIVE: To investigate whether mutations in the SURF1 gene are a cause of Charcot-Marie-Tooth (CMT) disease.METHODS: We describe 2 patients from a consanguineous family with demyelinating autosomal recessive CMT disease (CMT4) associated with the homozygous splice site mutation c.107-2A>G in the SURF1 gene, encoding an assembly factor of the mitochondrial respiratory chain complex IV. This observation led us to hypothesize that mutations in SURF1 might be an unrecognized cause of CMT4, and we investigated SURF1 in a total of 40 unrelated patients with CMT4 after exclusion of mutations in known CMT4 genes. The functional impact of c.107-2A>G on splicing, amount of SURF1 protein, and on complex IV activity and assembly was analyzed.RESULTS: Another patient with CMT4 was found to harbor 2 additional SURF1 mutations. All 3 patients with SURF1-associated CMT4 presented with severe childhood-onset neuropathy, motor nerve conduction velocities <25 m/s, and lactic acidosis. Two patients had brain MRI abnormalities, including putaminal and periaqueductal lesions, and developed cerebellar ataxia years after polyneuropathy. The c.107-2A>G mutation produced no normally spliced transcript, leading to SURF1 absence. However, complex IV remained partially functional in muscle and fibroblasts.CONCLUSIONS: We found SURF1 mutations in 5% of families (2/41) presenting with CMT4. SURF1 should be systematically screened in patients with childhood-onset severe demyelinating neuropathy and additional features such as lactic acidosis, brain MRI abnormalities, and cerebellar ataxia developing years after polyneuropathy.

DOI10.1212/WNL.0b013e3182a4a518
Alternate JournalNeurology
Citation Key10.1212/WNL.0b013e3182a4a518
PubMed ID24027061
PubMed Central IDPMC3888171