Abstract
Mutations in STXBP1 have recently been identified as a cause of infantile epileptic encephalopathy. The underlying mechanism of the disorder remains unclear and, recently, several case reports have described broad and progressive neurological phenotypes in addition to early-onset epilepsy. Herein, we describe a patient with early-onset epilepsy who subsequently developed a progressive neurological phenotype including parkinsonism in her early teens. A de novo mutation in STXBP1 (c.416C>T, p.(Pro139Leu)) was detected with exome sequencing together with profound impairment of complex I of the mitochondrial respiratory chain on muscle biopsy. These findings implicate a secondary impairment of mitochondrial function in the progressive nature of the disease phenotype.
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References
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Study funding
Dr. Michael Keogh is a Wellcome Trust Clinical Research Training Fellow. Professor Chinnery is a Wellcome Trust Senior Fellow in Clinical Science and National Institute for Health Research senior investigator. He receives funding from the Medical Research Council and the National Institute for Health Research Biomedical Research Centre for Ageing and Age-Related Disease award to the Newcastle upon Tyne Foundation Hospitals National Health Service Trust.
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The authors report no disclosures relevant to the manuscript and no conflict of interest.
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Keogh, M.J., Daud, D., Pyle, A. et al. A novel de novo STXBP1 mutation is associated with mitochondrial complex I deficiency and late-onset juvenile-onset parkinsonism. Neurogenetics 16, 65–67 (2015). https://doi.org/10.1007/s10048-014-0431-z
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DOI: https://doi.org/10.1007/s10048-014-0431-z