Bugiardin, E, Bottani, E, Marchet, S, Poole, OV, Beninca, C, Horga, A, Woodward, C, Lam, A, Hargreaves, IP, Chalasani, A, Valerio, A, Lamantea, E, Venner, K, Holton, JL, Zeviani, M, Houlden, H, Quinlivan, R, Lamperti, C, Hanna, MG and Pitceathly, RDS (2020) Expanding the molecular and phenotypic spectrum of truncating MT-ATP6 mutations. Neurology Genetics, 6 (1). ISSN 2376-7839

Preview

Text Expanding_the_molecular_and_phenotypic_spectrum_of (1).pdf - Published Version Available under License Creative Commons Attribution. Download (603kB) | Preview

Abstract

Objective To describe the clinical and functional consequences of 1 novel and 1 previously reported truncating MT-ATP6 mutation.
Methods Three unrelated probands with mitochondrial encephalomyopathy harboring truncating MT-ATP6 mutations are reported. Transmitochondrial cybrid cell studies were used to confirm pathogenicity of 1 novel variant, and the effects of all 3 mutations on ATPase 6 and complex V structure and function were investigated.
Results Patient 1 presented with adult-onset cerebellar ataxia, chronic kidney disease, and diabetes, whereas patient 2 had myoclonic epilepsy and cerebellar ataxia; both harbored the novel m.8782G>A; p.(Gly86*) mutation. Patient 3 exhibited cognitive decline, with posterior white matter abnormalities on brain MRI, and severely impaired renal function requiring transplantation. The m.8618dup; p.(Thr33Hisfs*32) mutation, previously associated with neurogenic muscle weakness, ataxia, and retinitis pigmentosa, was identified. All 3 probands demonstrated a broad range of heteroplasmy across different tissue types. Blue-native gel electrophoresis of cultured fibroblasts and skeletal muscle tissue confirmed multiple bands, suggestive of impaired complex V assembly. Microscale oxygraphy showed reduced basal respiration and adenosine triphosphate synthesis, while reactive oxygen species generation was increased. Transmitochondrial cybrid cell lines studies confirmed the deleterious effects of the novel m.8782 G>A; p.(Gly86*) mutation.
Conclusions We expand the clinical and molecular spectrum of MT-ATP6-related mitochondrial disorders to include leukodystrophy, renal disease, and myoclonic epilepsy with cerebellar ataxia. Truncating MT-ATP6 mutations may exhibit highly variable mutant levels across different tissue types, an important consideration during genetic counseling.

Item Type:	Article
Subjects:	Q Science > QH Natural history > QH301 Biology Q Science > QR Microbiology R Medicine > RM Therapeutics. Pharmacology R Medicine > RS Pharmacy and materia medica
Divisions:	Pharmacy & Biomolecular Sciences
Publisher:	Lippincott, Williams & Wilkins
Date Deposited:	12 Feb 2020 10:10
Last Modified:	04 Sep 2021 07:54
DOI or ID number:	10.1212/NXG.0000000000000381
URI:	https://researchonline.ljmu.ac.uk/id/eprint/12246

View Item