Table of Contents
ISRN Cardiology
Volume 2012 (2012), Article ID 251723, 6 pages
http://dx.doi.org/10.5402/2012/251723
Clinical Study

Novel m.15434C > A (p.230L > I) Mitochondrial Cytb Gene Missense Mutation Associated with Dilated Cardiomyopathy

1Genetics Laboratory and Research Unit of Genetics Epidemiology and Molecular, Faculty of Medicine of Tunis, Tunis 1007, Tunisia
2Biochemistry Laboratory and Research Unit of Human Nutrition & Metabolic Disorders, Faculty of Medicine of Monastir, Monastir 5000, Tunisia
3Services des Explorations Fonctionnelles Cardiologiques, Hôpital La Rabta de Tunis, Tunisia
4Krankenanstalt Rudolfstiftung, Danube University Krems, Postfach 20, 1180 Vienna, Austria

Received 9 April 2012; Accepted 9 May 2012

Academic Editors: F. Boucher and I. Morano

Copyright © 2012 Sinda Zarrouk Mahjoub et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background. Previously it has been shown that various types of hypertrophic and dilative cardiomyopathy (hCMP, dCMP) can be attributed to disturbed mitochondrial oxidative energy metabolism. Several studies described mutations in mitochondrial DNA-located genes encoding for subunits of respiratory chain complexes, including the cytochrome b gene (MT-CYB), causing CMPs. Methods and Results. In the present study the MT-CYB gene was analysed in 30 patients with hCMP, 40 patients with dCMP, and 50 controls for alterations. Altogether, 27 MT-CYB variants were detected. Twenty-four of them were single nucleotide polymorphisms defining common haplogroups. The variant m.15434C > A was found in a single patient with severe dCMP and assessed as novel mutation, since it was not found in healthy controls or available data sets, and was nonhaplogroup associated with Phylotree. This variant altered an amino acid (L230I) with a high interspecific amino acid conservation index ( C I = 9 7 . 7 %) indicative of the functional importance of the residue. Conclusions. Though the L230I mutation seems to play a causative role for dCMP, prospective studies on yeast or transgenic mice models with defined mutation are warranted to study the pathogenetic impact of this mutation.