title: Looking for differences in copy number between blood and brain in sporadic amyotrophic lateral sclerosis.
abstract: BACKGROUND
  Most analyses of blood DNA in sporadic neuromuscular disorders have been inconclusive. This may be because some genetic variants occur only in brain tissue. We therefore looked for copy number variants (CNVs) in both blood and brain in patients with sporadic amyotrophic lateral sclerosis (SALS).
  
  
  METHODS
  Genome-wide CNVs were compared in blood and brain from 32 SALS patients and from 26 normal (control) brains, using Affymetrix 6.0 arrays.
  
  
  RESULTS
  There were 410 CNVs present in brain but not blood (somatic CNVs) in 94% of the patients (median 8 CNVs per patient). Twenty-four of the somatic CNVs were rare, were not found in control brains, and overlapped with genes.
  
  
  CONCLUSIONS
  Brain-specific CNVs may be common and appear to be present in a proportion of patients with SALS. The more detailed copy number analysis that is becoming available with massively parallel sequencing may uncover brain-specific CNVs that underlie some cases of SALS.
authors.affiliation: The Stacey Motor Neuron Disease Laboratory, Department of Pathology, Neuropathology Division, University of Sydney, Sydney, New South Wales 2006, Australia. roger.pamphlett@sydney.edu.au
authors.forename: Roger
authors.initials: R
authors.lastname: Pamphlett
authors.forename: Julia M
authors.initials: JM
authors.lastname: Morahan
authors.forename: Natasha
authors.initials: N
authors.lastname: Luquin
authors.forename: Bing
authors.initials: B
authors.lastname: Yu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000097:blood / Q000235:genetics / Q000473:pathology; D001769:Blood / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D056915:DNA Copy Number Variations / Q000235:genetics*; D005260:Female; D020869:Gene Expression Profiling; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study; D006801:Humans; D008297:Male; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods