Case report: a novel frameshift mutation in the mitochondrial cytochrome c oxidase II gene causing mitochondrial disorder

BMC Neurology
Laura KytövuoriKari Majamaa

Abstract

Mitochondrial cytochrome c oxidase 2, MT-CO2, encodes one of the three subunits, which form the catalytic core of cytochrome c oxidase (COX), complex IV. Mutations in MT-CO2 are rare and the associated phenotypes are variable including nonsyndromic and syndromic forms of mitochondrial diseases. We describe a 30-year-old man with cognitive decline, epilepsy, psychosis, exercise intolerance, sensorineural hearing impairment, retinitis pigmentosa, cataract and lactic acidosis. COX-deficient fibers and ragged red fibers were abundant in the muscle. Sequencing of mitochondrial DNA (mtDNA) revealed a novel frameshift mutation m.8156delG that was predicted to cause altered C-terminal amino acid sequence and to lead to truncation of the COX subunit 2. The deletion was heteroplasmic being present in 26% of the mtDNA in blood, 33% in buccal mucosa and 95% in muscle. Deletion heteroplasmy correlated with COX-deficiency in muscle histochemistry. The mother and the siblings of the proband did not harbor the deletion. The clinical features and muscle histology of the proband suggested a mitochondrial disorder. The m.8156delG deletion is a new addition to the short list of pathogenic mutations in the mtDNA-encoded subunits of COX. This case i...Continue Reading

References

Jan 1, 1996·Methods in Enzymology·E A ShoubridgeL Boulet
Jun 23, 1998·American Journal of Human Genetics·M G HannaN W Wood
Sep 16, 1999·American Journal of Human Genetics·S RahmanA H Schapira
Jan 22, 2004·Neuromuscular Disorders : NMD·Robert McFarlandDouglass M Turnbull
Dec 21, 2004·Nucleic Acids Research·Marty C BrandonDouglas C Wallace
Feb 5, 2008·Journal of Medical Genetics·W RossmanithR E Bittner
May 24, 2008·American Journal of Human Genetics·Valeria MassaMassimo Zeviani
Nov 6, 2012·American Journal of Human Genetics·Alessia IndrieriBrunella Franco
Apr 26, 2013·Neurology·Christoffer Rasmus VissingJohn Vissing
Jul 13, 2013·Human Molecular Genetics·Sally SpendiffDoug M Turnbull
Jul 24, 2013·Human Mutation·Scot C LearyEric A Shoubridge
Aug 26, 2014·American Journal of Human Genetics·Gen TamiyaKiyoshi Hayasaka
Dec 20, 2015·Brain : a Journal of Neurology·Kerstin HallmannWolfram S Kunz

❮ Previous
Next ❯

Citations

Apr 18, 2021·Neuromuscular Disorders : NMD·Wei WangChuanzhu Yan

❮ Previous
Next ❯

Methods Mentioned

BETA
electrophoresis
PCR
biopsies

Software Mentioned

Zeiss

Related Concepts

Related Feeds

Auditory Perception

Auditory perception is the ability to receive and interpret information attained by the ears. Here is the latest research on factors and underlying mechanisms that influence auditory perception.