An expanded GGGGCC hexanucleotide of more than 30 repeats (termed (G4C2)<sub>30+</sub>) within C9orf72 is the most prominent mutation in familial frontotemporal degeneration (FTD) and amyotrophic lateral sclerosis (ALS) (termed C9<sup>+</sup>).
The C9ORF72 mutation is the most common cause of familial FTD, recent pathological descriptions challenge existing TDP-43 based hypotheses of sporadic FTD pathogenesis.
Chief among these was the discovery that a large repeat expansion in the C9ORF72 gene is responsible for an unprecedented portion of familial and sporadic ALS cases.
A hexanucleotide GGGGCC repeat expansion in the noncoding region of the C9ORF72 gene is the most common genetic abnormality in familial and sporadic amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD).
A massive intronic GGGGCC hexanucleotide repeat expansion in C9ORF72 has recently been identified as the most common cause of familial and sporadic amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD).
A hexanucleotide repeat expansion in the first intron of C9ORF72 has been shown to be responsible for a high number of familial cases of amyotrophic lateral sclerosis or frontotemporal lobar degeneration (FTLD).
Identification of C9orf72 repeat expansions in patients without a family history of ALS challenges the traditional division between familial and sporadic disease.
A repeat expansion in the C9orf72 gene has recently been identified as a major cause of familial and sporadic frontotemporal lobar degeneration and amyotrophic lateral sclerosis.
We therefore investigated the frequency of the C9orf72 repeat expansion in 254 Korean patients with familial (n = 8) and sporadic (n = 246) ALS and found that none of the patients had the expansion.
However, when ALS is present, all cases show a clear histological phenotype with TDP-43 aggregated proteins, and familial forms are associated with expansions in C9orf72.
Expansion of a GGGGCC hexanucleotide repeat upstream of the C9orf72 coding region is the most common cause of familial frontotemporal lobar degeneration and amyotrophic lateral sclerosis (FTLD/ALS), but the pathomechanisms involved are unknown.
Hexanucleotide repeat expansions in the C9ORF72 gene have been shown to be responsible for both familial and sporadic frontotemporal dementia/amyotrophic lateral sclerosis.
The scientific scenario of amyotrophic lateral sclerosis (ALS) has dramatically changed since TDP-43 aggregates were discovered in 2006 as the main component of the neuronal inclusions seen in the disease, and more recently, when the implication of C9ORF72 expansion in familial and sporadic cases of ALS and frontotemporal dementia was confirmed.
In amyotrophic lateral sclerosis (ALS) patients with known genetic cause, mutations in chromosome 9 open reading frame 72 (C9orf72) and superoxide dismutase 1 (SOD1) account for most familial and late-onset sporadic cases, whereas mutations in fused in sarcoma (FUS) can be identified in just around 5% of familial and 1% of overall sporadic cases.
Expanded GGGGCC hexanucleotide repeats in the promoter of the C9ORF72 gene have recently been identified in frontotemporal dementia (FTD), Amyotrophic Lateral Sclerosis (ALS) and ALS-FTD and appear as the most common genetic cause of familial (FALS) and sporadic (SALS) forms of ALS.
Hexanucleotide repeat expansions in C9ORF72 are a common cause of familial and apparently sporadic amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD).
The identification of mutations in transactive response DNA-binding protein gene (TARDBP), fused in sarcoma (FUS) and, more recently, a GGGGCC-hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9ORF72) and their link with familial ALS have provided new avenues of investigation and hypotheses on the pathophysiology of this devastating disease.
A hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9ORF72) gene has recently been described as a cause of familial and sporadic frontotemporal lobar degeneration.
Our findings indicate that the C9ORF72 mutation is a major cause of familial frontotemporal dementia with TDP-43 pathology, that likely accounts for the majority of families with combined frontotemporal dementia/amyotrophic lateral sclerosis presentation, and further support the concept that frontotemporal dementia and amyotrophic lateral sclerosis represent a clinicopathological spectrum of disease with overlapping molecular pathogenesis.
Hexanucleotide repeat expansions in the C9orf72 gene are a common genetic cause of familial and sporadic amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD).
An intronic expansion of a hexanucleotide GGGGCC repeat in the C9ORF72 gene has recently been shown to be an important cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) in familial and sporadic cases.