Wolf-Hirschhorn Syndrome deletion 4p16.3 by FISH*

Test Code

F WH*

Test Synonyms

del(4)(p16.3)

Methodology

Fluorescence in situ Hybridization (FISH)
*Performed by affiliate laboratory

Turnaround Time

7-9 days

Specimen Requirements

5mL peripheral blood in sodium heparin
3mL bone marrow in sodium heparin
Fixed cytogenetically prepared cells in sterile centrifuge tube with pellet visible in 3:1, Methanol:Acetic Acid

Specimen Stability

Blood and bone marrow = 4°C to 25°C, specimens are stable up to 72 hours
Fixed cell pellets are stable for years when stored at -28°C to 15°C

Storage & Handling

4°C to 25°C during transit, but specimens may be transported on refrigerated gel packs. Do not allow the gel pack to come in contact with the specimen. Do not freeze. Extreme temperatures should be avoided.

Causes for Rejection

Clotted specimen; Specimen exposed to extreme temperature; Anticoagulant or collection vessel toxic to cells; Insufficient number of cells; Specimen exposed to fixative

Reference Range

Presence or absence of the microdeletion

It is recommended that all FISH studies be done in conjunction with routine cytogenetic studies. If the FISH result is normal, a chromosome analysis allows identification of more complex abnormalities.

Description

Wolf-Hirschhorn syndrome, causing deletion of the short arm of chromosome 4, affects approximately 1 in 50,000 births.

References

Battaglia A. (2008). Update on the clinical features and natural history of Wolf-Hirschhorn (4p-) syndrome: experience with 87 patients and recommendations for routine health supervision. Am J Med Genet C Semin Med Genet. 15;148C(4):246-51.