title: Sporadic myopathy, myoclonus, leukoencephalopathy, neurosensory deafness, hypertrophic cardiomyopathy and insulin resistance associated with the mitochondrial 8306 T>C MTTK mutation.
abstract: We report a new T8306C transition in the D-stem of the MTTK gene of a 67-year-old man who manifested severe adult onset myopathy, myoclonus, leukoencephalopathy, neurosensory hypoacusis, hypertrophic cardiomyopathy and insulin resistance. No other family member was affected, suggesting that our patient was a sporadic case. The T8306C mutation was heteroplasmic in several tissues of the proband, while it was absent from his asymptomatic siblings. Single fibre analysis confirmed the segregation of higher mutational load in cytochrome c oxidase-deficient fibres. The mutation T8306C is predicted to disrupt a highly conserved base pair and was not found in more than 120 controls. This finding broadens the phenotypic and molecular spectrum of mitochondrial tRNA(Lys) associated disorders.
authors.affiliation: Department of Neurological, Neurosurgical and Behavioural Sciences, University of Siena, Siena, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Cardaioli
authors.forename: Edoardo
authors.initials: E
authors.lastname: Malfatti
authors.forename: Carla
authors.initials: C
authors.lastname: Battisti
authors.forename: Paola
authors.initials: P
authors.lastname: Da Pozzo
authors.forename: Anna
authors.initials: A
authors.lastname: Rubegni
authors.forename: Gian Nicola
authors.initials: GN
authors.lastname: Gallus
authors.forename: Alessandro
authors.initials: A
authors.lastname: Malandrini
authors.forename: Antonio
authors.initials: A
authors.lastname: Federico
mesh_terms: D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000235:genetics*; D004252:DNA Mutational Analysis; D006313:Hearing Loss, Central / Q000150:complications / Q000235:genetics*; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics*; D056784:Leukoencephalopathies / Q000150:complications / Q000235:genetics*; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D009135:Muscular Diseases / Q000150:complications / Q000235:genetics*; D009154:Mutation / Q000235:genetics*; D009207:Myoclonus / Q000150:complications / Q000235:genetics*; D012357:RNA, Transfer, Lys / Q000235:genetics*
chemical_list: D012357:RNA, Transfer, Lys