Background:
            
                Fluorescent in situ hybridization (FISH) with a steroid sulfatase (STS) probe detects deletion in Xp22.3 associated with X-linked icthyosis, as well as placental steroid sulfatase deficiency, resulting in low estrogen production during pregnancy.
            
            Methodology:
            
                Slides are prepared per standard protocols. 10 metaphase cells are scored per probe.  This FISH test is used as a supplement to standard G-banded chromosome analysis.
            
            Specimen Requirements:
            
                
Blood:   
    - Adult - 3-5 mL drawn into a GREEN top sodium heparin vacutainer tube or into a pre-heparinized plastic syringe (use 0.2 cc sodium heparin, 1000 unit/mL).  Do NOT use lithium heparin. 
- Child - 1-2 mL, as above.
- Infant - 1-2 mL, as above.  
- Keep at room temperature and transport to laboratory as soon as possible.
- Contact Client Services at (855) 535-1522 for supplies and instructions.
A REQUISITION FORM MUST ACCOMPANY ALL SAMPLES.  Please include detailed clinical information, including ethnicity, clinical history, and family history.
            
            Test Performed (Days):
            
                Mon - Sat
            
            Turn Around Time:
            
                3 - 7 days
            
            Shipment Sensitivity Requirements:
            
                Ship via overnight express, using the FedEx priority overnight label provided.  Use cold pack to keep specimens cool but not frozen.  Contact Client Services at (855) 535-1522 for shipping kits and instructions.
            
            References:
            
                
            
            Additional Info: