Journal of Medical Cases, ISSN 1923-4155 print, 1923-4163 online, Open Access
Article copyright, the authors; Journal compilation copyright, J Med Cases and Elmer Press Inc
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Case Report

Volume 12, Number 11, November 2021, pages 455-459

Dilated Cardiomyopathy due to the Novel MT-CYB Missense Mutation m.14757T>C


Figure 1.
Figure 1. Upper panel: (a) muscle biopsy section stained for Gomori’s trichrome shows muscle fibers with normal distribution of mitochondria (magnification × 40). (b) Succinate dehydrogenase (SDH) staining shows a similar picture with some low dark blue fibers (magnification × 40) compared to a healthy control (c). Lower panel: automated sequence analysis of the region encompassing the m.14757T>C mutation of the proband’s mtDNA in muscle.


Table 1. Activities of Respiratory Chain Enzymes in the Muscle Extract of the Described Patient
Patient values are expressed in nmol/min/mg. SDH: succinate dehydrogenase; NADH: ubiquinone oxidoreductase.
Complex-I3019 - 43
Complex-III5191 - 161
Complex-II + III1314 - 30
Complex-IV4034 - 80
Citrate synthase125101 - 225
SDH2820 - 38
NADH dehydrogenase170209 - 383


Table 2. Prediction Data of Mutations Detected in the Index Patient
MutationAA1AA2PredictionAvailable dataPrediction basisSubstitution effectPrediction data
AA: amino acid; PSIC: position-specific independent counts; PHAT: predicted hydrophobic and transmembrane matrix.
M4TMediumPossibly damagingAlignment structureStructure1.1.1: structural effect, buried site, hydrophobicity change at buried sitePSIC score difference: 0.810. Normed accessibility: 0.13. Hydrophobicity change: 0.77
T194ABenignAlignementSequence annotationN/APHAT matrix element difference: 0