Mitochondrial DNA (mtDNA) is maternally inherited. After birth, secondary mtDNA defects can arise. MtDNA depletion is a reduction in the amount of mtDNA in particular tissues. Multiple deletions of mtDNA accumulate as somatic mutations in mainly postmitotic tissues. These disorders of mtDNA maintenance frequently show Mendelian inheritance. Positional cloning has identified several genes involv...

Congenital neutropenia comprises a variety of genetically heterogeneous phenotypic traits. Molecular elucidation of the underlying genetic defects has yielded important insights into the physiology of neutrophil differentiation and function. Non-syndromic variants of congenital neutropenia are caused by mutations in ELA2, HAX1, GFI1, or WAS. Syndromic variants of congenital neutropenia may be d...

Strabismus can be found in association with congenital heart diseases, for examples, in velocardiofacial (DiGeorge) syndrome, Down syndrome, mild dysmorphic features, in CHARGE association, Turner syndrome, Ullrich-Turner syndrome, cardiofaciocutaneous syndrome.1-4 Some types of strabismus is heritable (e.g. infantile esotropia syndrome), particularly the ones associated with multisystem disord...

PURPOSE OF REVIEW The aims of this review is to suggest a new nomenclature and classification system for the diseases currently categorized as neurodegeneration with brain iron accumulation (NBIA) or dystonia-parkinsonism, and to discuss the mechanisms implicated in the pathogenesis of these diseases. RECENT FINDINGS NBIA is a disease category encompassing syndromes with iron accumulation and...

The majority of studies investigating the molecular pathogenesis and cell biology underlying dystonia have been performed in individuals with primary dystonia. This includes monogenic forms such as DYT1and DYT6 dystonia, and primary focal dystonia which is likely to be multifactorial in origin. In recent years there has been renewed interest in non-primary forms of dystonia including the dyston...

The mitochondrial encephalomyopathies are a heterogeneous group of disorders characterized by mitochondrial dysfunction that produce multisystem symptoms. This disorder affects both the central and peripheral nervous systems, skeletal muscles, heart, endocrine glands, gastrointestinal tract, hematopoietic system, and kidneys (Table 1) [1]. Patients with mitochondrial encephalomyopathy can be di...

Context Endocrine disorders are common in individuals with mitochondrial disease. To develop evidence-based screening practices in this high-risk population, updated age-stratified estimates of the prevalence of endocrine conditions are needed. Objective To measure the point prevalence of selected endocrine disorders in individuals with mitochondrial disease. Design Setting and Patients The...

how to cite this article: heidari mm, khatami m, houshmand m, mahmoudi e, nafissi sh .increased prevalence 12308 a > g mutation in mitochondrialtrnaleu (cun) gene associated with earlier age of onset in friedreich ataxia. iranian journal of child neurology 2011;5(4):25-31. objective friedreich ataxia (frda) is an inherited recessive disorder. mitochondrial dna is a candidate modifying factor fo...

Acute hyperammonemia resulting from congenital urea cycle disorders, Reye syndrome or acute liver failure results in severe neuronal dysfunction, seizures and death. Increasing evidence suggests that acute hyperammonemia results in alterations of mitochondrial and cellular energy function resulting from ammonia-induced inhibition of the tricarboxylic acid cycle enzyme alpha-ketoglutarate dehydr...

BACKGROUND Mitochondrial DNA (mtDNA) content measured by different techniques cannot be compared between studies, and age- and tissue-related control values are hardly available. In the present study, we aimed to establish the normal reference range of mtDNA copy number in the Chinese population. METHODS Two healthy cohorts of 200 Chinese minors (0.1-18.0 years) and 200 adults (18.0-88.0 year...