Friedreich ataxia is a neurodegenerative disorder caused by the expansion of a GAA trinucleotide repeat sequence within the first intron of the FXN gene. Interruptions in the GAA repeat may serve to alleviate the inhibitory effects of the GAA expansion on FXN gene expression and to decrease pathogenicity. We have developed a simple and rapid PCR- and restriction enzyme-based assay to assess the...

Friedreich's ataxia (FRDA) is a hereditary neurodegenerative disease characterized by a reduced synthesis of the mitochondrial iron chaperon protein frataxin as a result of a large GAA triplet-repeat expansion within the first intron of the frataxin gene. Despite neurodegeneration being the prominent feature of this pathology involving both the central and the peripheral nervous system, informa...

Simple inorganic structures comprised of iron and sulfur are called [Fe-S] clusters. They likely represent one of the earliest prosthetic groups associated with the emergence of life on earth and continue to have essential roles in sustaining many metabolic processes in almost all existing life forms. For example, proteins that contain one or more [Fe-S] clusters, generally referred to as [Fe-S...

OBJECTIVE Friedreich's ataxia is the most common form of hereditary ataxia with autosomal recessive pattern. More than 96% of patients are homozygous for GAA repeat extension on both alleles in the first intron of FXN gene and the remaining patients have been shown to be heterozygous for a GAA extension in one allele and point mutation in other allele. MATERIALS & METHODS In this study, exons...

Friedreich ataxia (FA or FRDA) is an autosomal recessive neurodegenerative disorder caused by mutations in the frataxin (FXN) gene located on chromosome 9q. Discovery of the genetic cause of FA has led to an understanding of the clinical and basic science aspects of the disorder and has implications for therapeutic discoveries (1, 2 ). For example, a mutant mouse has been developed, allowing a ...

Friedreich's ataxia (FA) is a severe disorder with autosomal recessive inheritance that is caused by the abnormal expansion of GAA repeat in intron 1 of FRDA gen. This alteration leads to a partial silencing of frataxin transcription, causing a multisystem disorder disease that includes neurological and non-neurological damage. Recent studies have proven the effectiveness of neurotrophic factor...

We assessed structural elements of the retina in individuals with Friedreich ataxia (FRDA) and in mouse models of FRDA, as well as functions of the retinal pigment epithelium (RPE) in FRDA using induced pluripotent stem cells (iPSCs). We analyzed the retina of the FRDA mouse models YG22R and YG8R containing a human FRATAXIN (FXN) transgene by histology. We complemented this work with post-morte...

BACKGROUND Expansion of an unstable GAA*TTC repeat in the first intron of the FXN gene causes Friedreich ataxia by reducing frataxin expression. Structure formation by the repeat has been implicated in both frataxin repression and GAA*TTC instability. The GAA*TTC sequence is capable of adopting multiple non-B DNA structures including Y*R*Y and R*R*Y triplexes. Lower pH promotes the formation of...

Friedreich ataxia, the most prevalent inherited ataxia, is caused by an expanded GAA triplet-repeat sequence in intron 1 of the FXN gene. Repressive chromatin spreads from the expanded GAA triplet-repeat sequence to cause epigenetic silencing of the FXN promoter via altered nucleosomal positioning and reduced chromatin accessibility. Indeed, deficient transcriptional initiation is the predomina...