FISH Analysis, Smith‑Magenis Syndrome
Use
This test can detect microdeletions in the 17p11.2 region associated with Smith‑Magenis syndrome. Approximately 95% of patients with this syndrome have deletions detectable by fluorescence in situ hybridization targeting the critical region. It is intended for patients with clinical features suspicious for Smith‑Magenis syndrome or for those with a possible 17p deletion identified by standard chromosome analysis. ([saintfrancis.com](https://www.saintfrancis.com/physicians/laboratory-testing/cytogenetics/available-tests/fish-analysis-smith-magenis-syndrome?utm_source=openai))
Special Instructions
Not provided.
Limitations
Approximately 95% of patients with Smith‑Magenis syndrome have deletions detectable by this method; rare cases may have deletions outside the probed region or mosaicism evading detection. Uses dual‑color FISH on metaphase and interphase cells; limits of detection inherent to FISH resolution apply. ([saintfrancis.com](https://www.saintfrancis.com/physicians/laboratory-testing/cytogenetics/available-tests/fish-analysis-smith-magenis-syndrome?utm_source=openai))
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
Unknown CNV
Copy Number Region
Result Turnaround Time
7-10 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3‑5 mL peripheral blood in sodium heparin (green) for children and adults; 1‑2 mL for newborns
Minimum Volume
2 mL for children and adults; 1 mL for newborns
Container
Sodium heparin (green) tube
Storage Instructions
Transport at 20‑25 °C
Causes for Rejection
Frozen or clotted specimens; specimens in anticoagulants other than sodium heparin
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 24 hours |
| Refrigerated | 72 hours |
| Frozen | Unacceptable |
Other tests from different labs that may be relevant