Abstract
Abstract
Background
Charcot-Marie-Tooth disease (CMT) type 4B3 (CMT4B3) is a rare form of genetic neuropathy associated with variants in the MTMR5/SBF1 gene. MTMR5/SBF1 is a pseudophosphatase predicted to regulate endo-lysosomal trafficking in tandem with other MTMRs. Although almost ubiquitously expressed, pathogenic variants primarily impact on the peripheral nervous system, corroborating the involvement of MTMR5/SBF1 and its molecular partners in Schwann cells-mediated myelinization.
Case presentation
We report a case of severe CMT4B3 characterized by early-onset motor and axonal polyneuropathy in an Italian child in absence of any evidence of brain and spine MRI abnormalities or intellectual disability and with a biochemical profile suggestive of mitochondrial disease. Using an integrated approach combining both NGS gene panels and WES analysis, we identified two novel compound heterozygous missense variants in MTMR5/SBF1 gene, p.R763H (c.2291G > A) and p.G1064E (c.3194G > A). Studies in muscle identified partial defects of oxidative metabolism.
Conclusion
We describe the first case of an early onset severe polyneuropathy with motor and axonal involvement, due to recessive variants in the MTMR5/SBF1 gene, with no evidence of brain and spine MRI abnormalities,
intellectual disability, no clinical and neurophysiological evidences of distal sensory impairment, and rapid neuromuscular deterioration. This report suggests that MTMR5/SBF1 should be considered in cases of infantile-onset CMT with secondary mitochondrial dysfunction.
Publisher
Springer Science and Business Media LLC
Subject
Genetics(clinical),Genetics
Reference30 articles.
1. Jerath NU, Shy ME. Hereditary motor and sensory neuropathies: understanding molecular pathogenesis could lead to future treatment strategies. Biochim Biophys Acta. 2015;1852(4):667–78.
2. Barisic N, Claeys KG, Sirotkovic-Skerlev M, Lofgren A, Nelis E, De Jonghe P, Timmerman V. Charcot-Marie-Tooth disease: a clinico-genetic confrontation. Ann Hum Genet. 2008;72(Pt 3):416–41.
3. Bird TD. Charcot-Marie-Tooth (CMT) hereditary neuropathy overview. In: Adam MP, Ardinger HH, Pagon RA, Wallace SE, Bean LJH, Stephens K, Amemiya A, editors. GeneReviews. Seattle: University of Washington; 1993.
4. Previtali SC, Quattrini A, Bolino A. Charcot-Marie-Tooth type 4B demyelinating neuropathy: deciphering the role of MTMR phosphatases. Expert Rev Mol Med. 2007;9(25):1–16.
5. Pareyson D, Stojkovic T, Reilly MM, Leonard-Louis S, Laura M, Blake J, Parman Y, Battaloglu E, Tazir M, Bellatache M, et al. A multicenter retrospective study of charcot-marie-tooth disease type 4B (CMT4B) associated with mutations in myotubularin-related proteins (MTMRs). Ann Neurol. 2019;86(1):55–67.
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