title: No GGGGCC-hexanucleotide repeat expansion in C9ORF72 in parkinsonism patients in Sweden.
abstract: An intronic GGGGCC-hexanucleotide repeat expansion in C9ORF72 was recently identified as a major cause of amyotrophic lateral sclerosis and frontotemporal dementia. Some amyotrophic lateral sclerosis patients have signs of parkinsonism, and many parkinsonism patients develop dementia. In this study we examined if the hexanucleotide repeat expansion was present in parkinsonism patients, to clarify if there could be a relationship between the repeat expansion and disease. We studied the size of the hexanucleotide repeat expansion in a well defined population-based cohort of 135 Parkinson's disease patients and 39 patients with atypical parkinsonism and compared with 645 Swedish control subjects. We found no correlation between Parkinson's disease or atypical parkinsonism and the size of the GGGGCC repeat expansion in C9ORF72. In conclusion, this GGGGCC-repeat expansion in C9ORF72 is not a cause of parkinsonism in the Swedish population.
authors.affiliation: Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden. chizuru.akimoto@neuro.umu.se
authors.forename: Chizuru
authors.initials: C
authors.lastname: Akimoto
authors.forename: Lars
authors.initials: L
authors.lastname: Forsgren
authors.forename: Jan
authors.initials: J
authors.lastname: Linder
authors.forename: Anna
authors.initials: A
authors.lastname: Birve
authors.forename: Irene
authors.initials: I
authors.lastname: Backlund
authors.forename: Jörgen
authors.initials: J
authors.lastname: Andersson
authors.forename: Ann-Charloth
authors.initials: AC
authors.lastname: Nilsson
authors.forename: Helena
authors.initials: H
authors.lastname: Alstermark
authors.forename: Peter M
authors.initials: PM
authors.lastname: Andersen
mesh_terms: D000368:Aged; D001483:Base Sequence; D000073885:C9orf72 Protein; D042622:DNA Repeat Expansion / Q000235:genetics*; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000453:epidemiology* / Q000235:genetics*; D006801:Humans; D015810:Linkage Disequilibrium / Q000235:genetics; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010300:Parkinson Disease / Q000453:epidemiology* / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D015995:Prevalence; D011506:Proteins / Q000235:genetics*; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
chemical_list: D000073885:C9orf72 Protein; C568651:C9orf72 protein, human; D005819:Genetic Markers; D011506:Proteins