The m.7510T>C mutation : hearing impairment and a complex neurologic phenotype
Kytövuori, Laura; Gardberg, Maria; Majamaa, Kari; Martikainen, Mika H. (2017-12-28)
Kytövuori L, Gardberg M, Majamaa K, Martikainen MH. The m.7510T>C mutation: Hearing impairment and a complex neurologic phenotype. Brain Behav. 2017;7:e00859. https://doi.org/10.1002/brb3.859
© 2017 The Authors. Brain and Behavior published by Wiley Periodicals, Inc. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Objectives: Mutations in mitochondrial DNA cause a variety of clinical phenotypes ranging from a mild hearing impairment (HI) to severe encephalomyopathy. The MT-TS1 gene is a hotspot for mutations causing HI. The m.7510T>C mutation in MT-TS1 has been previously associated with non-syndromic HI in four families from different ethnic backgrounds.
Materials and Methods: We describe the clinical, genetic, and histopathological findings in a Finnish family with the heteroplasmic m.7510T>C mutation in mitochondrial DNA.
Results: The family proband presented with a progressive mitochondrial disease phenotype including migraine, epilepsy, mild ataxia, and cognitive impairment in addition to HI. One young adult presented with HI only. Other family members had a mild phenotype comprising ataxia and tremor in addition to HI. Mutation heteroplasmy was 90% in the blood of maternal grandmother and ≥99% in the muscle and blood of the three other family members. Muscle histology was consistent with mitochondrial myopathy in three family members. The mitochondrial haplogroup of the family was a different branch of the haplogroup H than in the previous reports of this mutation.
Conclusion: Our results suggest that, in addition to sensorineural HI, the m.7510T>C mutation is associated with a spectrum of mitochondrial disease clinical features including migraine, epilepsy, cognitive impairment, ataxia, and tremor, and with evidence of mitochondrial myopathy.
- Avoin saatavuus