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| Test Description |
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Test Name
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FISH, Angelman Syndrome
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Synonym(s)
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Angelman Syndrome Microdeletion FISH
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Description
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Fluorescence In Situ Hybridization (FISH) is performed to detect microdeletions of chromosome 15 at band 15q11.2-q13, as seen in about 70% of patients with Angelman syndrome. Other causes of Angelman syndrome, such as paternal uniparental disomy, genetic imprinting abnormalities or mutations in the UBE3A gene will not be detected.
Note: Cytogenetics, Blood, Constitutional Karyotype must be ordered on the same specimen, unless cytogenetic analysis has been performed on a prior specimen |
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Methodology
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A fluorescently labeled DNA probe for UBE3A, the critical gene implicated in Angelman syndrome, is hybridized to unstained metaphase chromosomes. Ten cells are evaluated for the presence of 2 signals (normal) or 1 signal (deletion).
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Performed
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Daily |
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Turnaround Time
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8 - 10 Days |
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Specimen Requirements
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Minimum 3 mL aseptically collected blood in a 5 mL green top, sodium heparin tube (or 2 mL pediatric green top, sodium heparin tube). DO NOT use lithium heparin tubes.
Note: Deliver to lab at room temperature within 24 hours. If collected over a weekend, call the laboratory to make arrangements for specimen delivery. May be refrigerated if not transported immediately. Do not freeze. Protect from heat or cold.
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Rejection Criteria
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Frozen, clotted, hemolyzed or grossly contaminated specimens. Incorrect anticoagulant used. |
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CPT Code(s)
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88271, 88273, 88291 (if routine cytogenetics not requested, add 88230) |
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Reference Range
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See interpretive report |
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Contact
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Cytogenetics Lab: (214) 645-7000
Customer Service: (214) 645-7057 or Toll Free (877) 887-8136
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Last Modified: Jan 9, 2008 |
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