title: High-resolution SNP microarray investigation of copy number variations on chromosome 18 in a control cohort.
abstract: Copy number variations (CNVs) as described in the healthy population are purported to contribute significantly to genetic heterogeneity. Recent studies have described CNVs using lymphoblastoid cell lines or by application of specifically developed algorithms to interrogate previously described data. However, the full extent of CNVs remains unclear. Using high-density SNP array, we have undertaken a comprehensive investigation of chromosome 18 for CNV discovery and characterisation of distribution and association with chromosome architecture. We identified 399 CNVs, of which loss represents 98%, 58% are less than 2.5 kb in size and 71% are intergenic. Intronic deletions account for the majority of copy number changes with gene involvement. Furthermore, one-third of CNVs do not have putative breakpoints within repetitive sequences. We conclude that replicative processes, mediated either by repetitive elements or microhomology, account for the majority of CNVs in the healthy population. Genomic instability involving the formation of a non-B structure is demonstrated in one region.
authors: ANU Medical School, Australian National University, Canberra, A.C.T., Australia. Nicole.chia@act.gov.au
authors: N L
authors: NL
authors: Chia
authors: M
authors: M
authors: Bryce
authors: P E
authors: PE
authors: Hickman
authors: J M
authors: JM
authors: Potter
authors: N
authors: N
authors: Glasgow
authors: G
authors: G
authors: Koerbin
authors: P
authors: P
authors: Danoy
authors: M A
authors: MA
authors: Brown
authors: J
authors: J
authors: Cavanaugh
mesh_terms: D000465:Algorithms; D058674:Chromosome Duplication; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics*; D015331:Cohort Studies; D056915:DNA Copy Number Variations; D005260:Female; D015894:Genome, Human; D042822:Genomic Instability; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007438:Introns; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide; D017384:Sequence Deletion