• Test Code:
  • Department:
    Constitutional FISH
  • Test Synonyms:
    Velocardiofacial syndromeVCFSDGSDeletion 22q11.2 syndrome
  • CPT Code(s):

Fluorescent in situ hybridization (FISH) with the TUPLE1 probe and control probe ARSA detects deletion/duplication in the velocardiofacial/DiGeorge syndrome region of 22q11.2.


Slides are prepared per standard protocols. 10 metaphase cells and 50 interphase cells are scored per probe.  This FISH test is used as a supplement to standard G-banded chromosome analysis.

Specimen Requirements:


  • 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:

5-12 days: Contact Lab at 855-KDL-1LAB (535-1522) - Time varies depending on number and type of tests performed.

Shipment Sensitivity Requirements:

  • Keep specimen at room temperature during transit. 
  • Do not use the cold pack provided in the KDL shipping kit. 
  • Ship the specimen overnight express, using the FedEx priority overnight label provided. 
  • The specimen must arrive at the lab no more than 24 hours after collection.


For 22q11.2 deletion syndrome clinical and testing review see NCBI GeneReviews:  http://www.ncbi.nlm.nih.gov/books/NBK1523/

Additional Info: