FISH Analysis - SRY Related Phenotypes
Use
FISH Analysis - SRY Related Phenotypes is a Fluorescence In Situ Hybridization test designed to analyze postnatal blood samples for SRY-related rearrangements, which are critical in the assessment of disorders of sex development. It utilizes probes specifically targeting the X centromere and SRY region simultaneously, allowing for the determination of SRY deletions or translocations to the X chromosome. This testing is especially pertinent for patients exhibiting clinical indicators such as ambiguous genitalia, cryptorchidism, or hypospadias at any stage of development. It is essential for ensuring accurate diagnosis and appropriate management of patients with variations in sexual development.
Special Instructions
Patients should provide samples drawn in Sodium Heparin tubes, ensuring they arrive at the laboratory within 48 hours without freezing. Collect 3-5cc for adults and children, while 1-2cc is sufficient for infants. It is essential to use appropriate sample collection methods as outlined. FISH analysis focuses solely on specific genetic rearrangements and does not conclusively rule out other associated disorders.
Limitations
The FISH assay is limited to identifying gain or loss of the SRY gene, which may not fully capture the complexity of genetic variations present in patients with disorders of sex development. The assay focuses predominantly on the X and Y chromosomes, thus missing potential abnormalities in autosomal chromosomes or other genomic rearrangements. Additionally, the assay cannot detect forms of genetic mosaicism that may be present. For comprehensive diagnosing, supplementary testing may be required to rule out other potential disruptions linked to aneuploidy or structural anomalies in chromosomes that are not evaluated by this FISH approach.
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
Result Turnaround Time
14 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood (Fresh)
Volume
3-5 cc (Adults/Children) or 1-2 cc (Infants <2 years)
Minimum Volume
3-5 cc (Adults/Children) or 1-2 cc (Infants <2 years)
Container
Sodium Heparin tube (Green-Top)
Collection Instructions
Draw blood in a Sodium Heparin (green-top) tube(s).
Storage Instructions
Ship the sample at room temperature.
Causes for Rejection
EDTA and plasma separator tubes (PST) are not acceptable for cytogenetic analysis.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |