Microdeletion analysis (prenatal) | FISH

Test DetailsDetects microdeletions: DiGeorge – Tuple1; Williams – ELN; Prader-Willi – SNRPN; Angelman – S10; Cri du Chat – EGR1; Wolf-Hirschhorn – WHS; Miller-Dieker – LIS1; Smith-Magenis – SMS; Steroid Sulfatase Deficiency – STS; SRY deletion – SRY/CEP X; sex chromosomes – CEP XY
MethodologyFluorescence in-situ hybridization
PerformedMonday – Saturday
Turnaround10 – 21 days
Specimen requirementsAmniotic fluid (AF), chorionic villi sampling (CVS), percutaneous umbilical blood sampling (PUBS)
Sample collectionAF: Discard first 2mL of amniotic fluid. Collect 15-25mL in a sterile syringe. Use sterile technique to transfer to 15mL sterile screw-top plastic conical tubes for transport. Do not centrifuge. CVS: Collect 15-40mg of budding villi in 50mL screw-top plastic conical tubes in sterile transport media (provided by cytogenetics lab). Do not centrifuge. PUBS: Collect 1-3mL in sterile, 15mL sodium heparin (green-top) Vacutainer tube. Collect under ultrasound guidance. Invert tube immediately upon completion of blood collection to prevent formation of clots.
Minimum sample volume10 mLs
Storage/Transport ConditionsRoom temperature
Unacceptable ConditionsWill not be accepted after three days
Special InstructionsRefrigerate if sample cannot be delivered within 24 hours; Send to Rapid Response or SLCH Central Receiving
CPT Code(s)88291×1, 88235×1, 88271×2, 88273×1, 88274×1