Steroid Sulfatase Deficiency deletion Xp22, x-linked ichthyosis by FISH*

Test Code

F STS*

Test Synonyms

del(X)(p22.32), X-linked ichthyosis

Associations

STS/CEP X

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 toxic to cells; Insufficient number of cells

Reference Range

See report

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

X-linked recessive ichthyosis is caused by a deletion of the steroid sulfatase gene located on the X chromosome at the p22.3 location. The abnormality is seen more in males and affects approximately 1 in 6,000.

References

NCBI steroid sulfatase deficiency, ichthyosis, x-linked.