Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Detection of unbalanced insertions by aCGH and FISH

ABSTRACT: Insertions occur when a segment of one chromosome is translocated and inserted into a new region of the same chromosome or a non-homologous chromosome. We report 69 cases with unbalanced insertions identified using array CGH and FISH, representing 1.25% of 5,683 cases referred to our laboratory for array CGH and found to have copy-number abnormalities. Although the majority of insertions were non-recurrent, several recurrent unbalanced insertions were detected, including three der(Y)ins(Y;18)(q?11.2;p11.32p11.32)pat inherited from parents carrying an unbalanced insertion. The clinical significance of these recurrent rearrangements is unclear, although the small size, limited gene content, and inheritance pattern of each suggests the phenotypic consequences may be benign. Moreover, cryptic, submicroscopic duplications were observed at or near the insertion sites in two patients, further confounding the clinical interpretation of these insertions. Using FISH, linear amplification and array CGH we identified a 126-kb duplicated region from 19p13.3 inserted into MECP2 at Xq28 in a patient with symptoms of Rett syndrome. Our results demonstrate that although the interpretation of most non-recurrent insertions is unclear without high-resolution insertion site characterization, the potential for an otherwise benign duplication to result in a clinically relevant outcome through the disruption of a gene necessitates the use of FISH to determine whether copy-number gains detected by array CGH represent tandem duplications or unbalanced insertions. Further follow-up testing using techniques such as linear amplification coupled with array CGH or sequencing should be used to determine gene involvement at the insertion site after FISH has identified the presence of an insertion. 88 total samples analyzed. No replicates included. Each sample run against a standard sex-matched control.

ORGANISM(S): Homo sapiens

SUBMITTER: Blake Ballif

PROVIDER: E-GEOD-27080 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Recurrence, submicroscopic complexity, and potential clinical relevance of copy gains detected by array CGH that are shown to be unbalanced insertions by FISH.

Neill Nicholas J NJ Ballif Blake C BC Lamb Allen N AN Parikh Sumit S Ravnan J Britt JB Schultz Roger A RA Torchia Beth S BS Rosenfeld Jill A JA Shaffer Lisa G LG

Genome research 20110307 4

Insertions occur when a segment of one chromosome is translocated and inserted into a new region of the same chromosome or a non-homologous chromosome. We report 71 cases with unbalanced insertions identified using array CGH and FISH in 4909 cases referred to our laboratory for array CGH and found to have copy-number abnormalities. Although the majority of insertions were non-recurrent, several recurrent unbalanced insertions were detected, including three der(Y)ins(Y;18)(q?11.2;p11.32p11.32)pat ...[more]

PMID: 21383316

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Dataset Information

Detection of unbalanced insertions by aCGH and FISH

Publications

Recurrence, submicroscopic complexity, and potential clinical relevance of copy gains detected by array CGH that are shown to be unbalanced insertions by FISH.

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