Corticobasal and ataxia syndromes widen the spectrum of C9ORF72 hexanucleotide expansion disease

TY - JOUR

T1 - Corticobasal and ataxia syndromes widen the spectrum of C9ORF72 hexanucleotide expansion disease

AU - Lindquist, Sg

AU - Duno, M

AU - Batbayli, M

AU - Puschmann, A

AU - Braendgaard, H

AU - Mardosiene, S

AU - Svenstrup, K

AU - Pinborg, Lh

AU - Vestergaard, K

AU - Hjermind, LE

AU - Stokholm, J

AU - Andersen, Bb

AU - Johannsen, P

AU - Nielsen, Jørgen Erik

N1 - © 2012 John Wiley & Sons A/S.

PY - 2013/3

Y1 - 2013/3

N2 - Recently, a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72 was reported as the cause of chromosome 9p21-linked frontotemporal dementia-amyotrophic lateral sclerosis (FTD-ALS). We here report the prevalence of the expansion in a hospital-based cohort and associated clinical features indicating a wider clinical spectrum of C9ORF72 disease than previously described. We studied 280 patients previously screened for mutations in genes involved in early onset autosomal dominant inherited dementia disorders. A repeat-primed polymerase chain reaction amplification assay was used to identify pathogenic GGGGCC expansions. As a potential modifier, confirmed cases were further investigated for abnormal CAG expansions in ATXN2. A pathogenic GGGGCC expansion was identified in a total of 14 probands. Three of these presented with atypical clinical features and were previously diagnosed with clinical olivopontocerebellar degeneration (OPCD), atypical Parkinsonian syndrome (APS) and a corticobasal syndrome (CBS). Further, the pathogenic expansion was identified in six FTD patients, four patients with FTD-ALS and one ALS patient. All confirmed cases had normal ATXN2 repeat sizes. Our study widens the clinical spectrum of C9ORF72related disease and confirms the hexanucleotide expansion as a prevalent cause of FTD-ALS disorders. There was no indication of a modifying effect of the ATXN2 gene.

AB - Recently, a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72 was reported as the cause of chromosome 9p21-linked frontotemporal dementia-amyotrophic lateral sclerosis (FTD-ALS). We here report the prevalence of the expansion in a hospital-based cohort and associated clinical features indicating a wider clinical spectrum of C9ORF72 disease than previously described. We studied 280 patients previously screened for mutations in genes involved in early onset autosomal dominant inherited dementia disorders. A repeat-primed polymerase chain reaction amplification assay was used to identify pathogenic GGGGCC expansions. As a potential modifier, confirmed cases were further investigated for abnormal CAG expansions in ATXN2. A pathogenic GGGGCC expansion was identified in a total of 14 probands. Three of these presented with atypical clinical features and were previously diagnosed with clinical olivopontocerebellar degeneration (OPCD), atypical Parkinsonian syndrome (APS) and a corticobasal syndrome (CBS). Further, the pathogenic expansion was identified in six FTD patients, four patients with FTD-ALS and one ALS patient. All confirmed cases had normal ATXN2 repeat sizes. Our study widens the clinical spectrum of C9ORF72related disease and confirms the hexanucleotide expansion as a prevalent cause of FTD-ALS disorders. There was no indication of a modifying effect of the ATXN2 gene.

U2 - 10.1111/j.1399-0004.2012.01903.x

DO - 10.1111/j.1399-0004.2012.01903.x

M3 - Journal article

C2 - 22650353

SN - 0009-9163

VL - 83

SP - 279

EP - 283

JO - Clinical Genetics

JF - Clinical Genetics

IS - 3

ER -