Dataset Information

Common and Novel TMEM70 Mutations in a Cohort of Italian Patients with Mitochondrial Encephalocardiomyopathy.

ABSTRACT: ATP synthase or complex V (cV) of the oxidative phosphorylation system is responsible for the production of ATP, dissipating the electrochemical gradient generated by the mitochondrial respiratory chain. In addition to maternally transmitted cV dysfunction caused by mutations in mtDNA genes (MT-ATP6 or MT-ATP8), encoding cV subunits, recessive mutations in the nuclear TMEM70 are the most frequent cause of ATP synthase deficiency.We report on a cohort of ten Italian patients presenting with neonatal lactic acidosis, respiratory distress, hypotonia, cardiomyopathy and psychomotor delay and harbouring mutations in TMEM70, including the common splice mutation and four novel variants. TMEM70 protein was virtually absent in all tested TMEM70 patients' specimens.The exact function of TMEM70 is not known, but it is considered to impact on cV assembly since TMEM70 mutations have been associated with isolated cV activity reduction. We detected a clear cV biochemical defect in TMEM70 patients' fibroblasts, whereas the assay was not reliable in frozen muscle. Nevertheless, the evaluation of the amount of holocomplexes in patients with TMEM70 mutations showed a nearly absent cV in muscles and a strong decrease of cV with accumulation of sub-assembly species in fibroblasts. In our cohort we found not only cV deficiencies but also impairment of other OXPHOS complexes. By ultrastructural analysis of muscle tissue from one patient with isolated cV deficiency, we found a severely impaired mitochondrial morphology with loss of the cristae. These findings indicate that cV impairment could indirectly alter other respiratory chain complex activities by disrupting the mitochondrial cristae structure.

SUBMITTER: Diodato D

PROVIDER: S-EPMC4270871 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Common and Novel TMEM70 Mutations in a Cohort of Italian Patients with Mitochondrial Encephalocardiomyopathy.

Diodato Daria D Invernizzi Federica F Lamantea Eleonora E Fagiolari Gigliola G Parini Rossella R Menni Francesca F Parenti Giancarlo G Bollani Lina L Pasquini Elisabetta E Donati Maria A MA Cassandrini Denise D Santorelli Filippo M FM Haack Tobias B TB Prokisch Holger H Ghezzi Daniele D Lamperti Costanza C Zeviani Massimo M

JIMD reports 20140417

ATP synthase or complex V (cV) of the oxidative phosphorylation system is responsible for the production of ATP, dissipating the electrochemical gradient generated by the mitochondrial respiratory chain. In addition to maternally transmitted cV dysfunction caused by mutations in mtDNA genes (MT-ATP6 or MT-ATP8), encoding cV subunits, recessive mutations in the nuclear TMEM70 are the most frequent cause of ATP synthase deficiency.We report on a cohort of ten Italian patients presenting with neona ...[more]

PMID: 24740313

Similar Datasets

Project description:Background:Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency and has a broad spectrum of clinical manifestations. Among non-infectious complications, an increased incidence of malignancies may have a special relevance for survival, but little is known about treatment efficacy on malignant complications. Methods:This was a monocenter retrospective study on CVID patients, designed to provide preliminary data for the investigation of the possible link between therapeutic delay and tumor incidence. Results:A total of 67 CVID subjects were included. The median diagnostic delay was 7.5 years (range: 0-63 years), and the median therapeutic delay was 8.5 years (range: 0-67 years). Malignancies were diagnosed in 18 (27%) patients. Eight out of 18 (44%) patients with a malignancy had lymphoma. Patients who developed a malignancy showed a longer therapeutic delay in comparison to patients with no malignancy, although no statistical significance was achieved (11 years vs 8 years, respectively, p?=?0.424). We observed a lower frequency of malignancy in CVID patients with reduced therapeutic delay compared with patients with therapeutic delay???10 years. With a therapeutic delay of?>?1 year, 74% had no tumor, and 25% had a tumor; with a therapeutic delay of?>?10 years, 65% had no tumor and 35% had a malignancy. Among patients who had no malignancy, 64% had a therapeutic delay of?<?10 years, and 36% had a therapeutic delay of???10 years. Among patients with malignancy, 47% of subjects had a therapeutic delay?<?10 years, and 53% a therapeutic delay???10 years. Conclusions:The observation of clinical characteristics of our patients with CVID may suggest that an early institution of IgG replacement therapy could be of benefit for the prevention of malignant complications.Name of the registry: Comitato Etico Regionale delle Marche. Trial registration number: 1505. Date of registration: 27/10/2016, Retrospectively registered URL of trial registry record: http://www.ospedaliriuniti.marche.it/portale/archivio13_cerm-ancona_0_446_1.html. The trial was not registered before the first participant was enrolled.

Project description:BackgroundLoeys-Dietz syndrome (LDS) is a rare autosomal dominant disorder showing the involvement of cutaneous, cardiovascular, craniofacial, and skeletal systems. In particular, LDS patients show arterial tortuosity with widespread vascular aneurysm and dissection, and have a high risk of aortic dissection or rupture at an early age and at aortic diameters that ordinarily are not predictive of these events. Recently, LDS has been subdivided in LDS type I (LDSI) and type II (LDSII) on the basis of the presence or the absence of cranio-facial involvement, respectively. Furthermore, LDSII patients display at least two of the major signs of vascular Ehlers-Danlos syndrome. LDS is caused by mutations in the transforming growth factor (TGF) beta-receptor I (TGFBR1) and II (TGFBR2) genes. The aim of this study was the clinical and molecular characterization of two LDS patients.MethodsThe exons and intronic flanking regions of TGFBR1 and TGFBR2 genes were amplified and sequence analysis was performed.ResultsPatient 1 was a boy showing dysmorphic signs, blue sclerae, high-arched palate, bifid uvula; skeletal system involvement, joint hypermobility, velvety and translucent skin, aortic root dilatation, tortuosity and elongation of the carotid arteries. These signs are consistent with an LDSI phenotype. The sequencing analysis disclosed the novel TGFBR1 p.Asp351Gly de novo mutation falling in the kinase domain of the receptor. Patient 2 was an adult woman showing ascending aorta aneurysm, with vascular complications following surgery intervention. Velvety and translucent skin, venous varicosities and wrist dislocation were present. These signs are consistent with an LDSII phenotype. In this patient and in her daughter, TGFBR2 genotyping disclosed in the kinase domain of the protein the novel p.Ile510Ser missense mutation.ConclusionWe report two novel mutations in the TGFBR1 and TGFBR2 genes in two patients affected with LDS and showing marked phenotypic variability. Due to the difficulties in the clinical approach to a TGFBR-related disease, among patients with vascular involvement, with or without aortic root dilatation and LDS cardinal features, genotyping is mandatory to clarify the diagnosis, and to assess the management, prognosis, and counselling issues.

Dataset Information

Common and Novel TMEM70 Mutations in a Cohort of Italian Patients with Mitochondrial Encephalocardiomyopathy.

Publications

Common and Novel TMEM70 Mutations in a Cohort of Italian Patients with Mitochondrial Encephalocardiomyopathy.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets