title: Length of normal alleles of C9ORF72 GGGGCC repeat do not influence disease phenotype.
abstract: Expansions of the noncoding GGGGCC hexanucleotide repeat in the Chromosome 9 open reading frame 72 (C9ORF72) gene cause frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). In this study we aimed to determine whether the length of the normal-unexpanded-allele of the GGGGCC repeat in C9ORF72 plays a role in the presentation of disease or affects age at onset in C9ORF72 mutation carriers. We also studied whether the GGGGCC repeat length confers risk or affects age at onset in FTD and ALS patients without C9ORF72 repeat expansions. C9ORF72 genotyping was performed in 580 FTD, 995 ALS, and 160 FTD-ALS patients, and 1444 controls, leading to the identification of 211 patients with pathogenic C9ORF72 repeat expansions. No meaningful association between the repeat length of the normal alleles of the GGGGCC repeat in C9ORF72 and disease phenotype or age at onset was observed in C9ORF72 mutation carriers or nonmutation carriers.
authors: Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA.
authors: Nicola J
authors: NJ
authors: Rutherford
authors: Michael G
authors: MG
authors: Heckman
authors: Mariely
authors: M
authors: Dejesus-Hernandez
authors: Matt C
authors: MC
authors: Baker
authors: Alexandra I
authors: AI
authors: Soto-Ortolaza
authors: Sruti
authors: S
authors: Rayaprolu
authors: Heather
authors: H
authors: Stewart
authors: Elizabeth
authors: E
authors: Finger
authors: Kathryn
authors: K
authors: Volkening
authors: William W
authors: WW
authors: Seeley
authors: Kimmo J
authors: KJ
authors: Hatanpaa
authors: Catherine
authors: C
authors: Lomen-Hoerth
authors: Andrew
authors: A
authors: Kertesz
authors: Eileen H
authors: EH
authors: Bigio
authors: Carol
authors: C
authors: Lippa
authors: David S
authors: DS
authors: Knopman
authors: Hans A
authors: HA
authors: Kretzschmar
authors: Manuela
authors: M
authors: Neumann
authors: Richard J
authors: RJ
authors: Caselli
authors: Charles L
authors: CL
authors: White
authors: Ian R
authors: IR
authors: Mackenzie
authors: Ronald C
authors: RC
authors: Petersen
authors: Michael J
authors: MJ
authors: Strong
authors: Bruce L
authors: BL
authors: Miller
authors: Bradley F
authors: BF
authors: Boeve
authors: Ryan J
authors: RJ
authors: Uitti
authors: Kevin B
authors: KB
authors: Boylan
authors: Zbigniew K
authors: ZK
authors: Wszolek
authors: Neill R
authors: NR
authors: Graff-Radford
authors: Dennis W
authors: DW
authors: Dickson
authors: Owen A
authors: OA
authors: Ross
authors: Rosa
authors: R
authors: Rademakers
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics*; D000073885:C9orf72 Protein; D042622:DNA Repeat Expansion / Q000235:genetics*; D005260:Female; D057180:Frontotemporal Dementia / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D011506:Proteins / Q000235:genetics*
chemical_list: D000073885:C9orf72 Protein; C568651:C9orf72 protein, human; D011506:Proteins