FISH for XIST
Test Mnemonic
XSTFSH
CPT Codes
- 88273 - QTY (1)
- 88271 - QTY (2)
Performing Laboratory
Cleveland Clinic Laboratories
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 5 mL | Blood | Sodium heparin (Green) | Ambient | Ambient | For newborn and infant draws, a minimum of 0.5ml whole blood is imposed. Unacceptable conditions: Frozen specimens, Paraffin-embedded specimens and clotted specimens. |
Alternate Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 5 mL | Other tube and container types may be acceptable. Contact client services to inquire further. |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 72 hours |
| Refrigerated | 72 hours |
| Frozen | Unacceptable |
Days Performed
Mon - Fri
Turnaround Time
5 - 7 days
Methodology
| Name | Description |
|---|---|
| Fluorescent In-Situ Hybridization (FISH) |
Reference Range
| FISH XST Interpretation | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Freetext | Refer to Report |
Clinical Info
The FISH for XST ascertains the sex chromosome composition and presence of the XST gene in individuals suspected with Turner syndrome 45,X. Additionally, characterizations of X chromosome structural abnormalities such as rings and marker chromosomes derived from the X chromosome are formulated with the XST gene status.