Trisomy Analysis (Chromosome 13, 18, 21) by DNA FISH, Newborn Smear
Blood, Bone Marrow
Green top (sodium heparin) tube
Cause for rejection:
Clotted, non-sterile, or frozen specimen
Mon-Fri (0700-1600) Sat (0900-1300)
Smears are prepared and pretreated, hybridized overnight with appropriate DNA probe(s), washed, and counterstained. 100-300 cells are analyzed using a fluorescence microscope and images are captured digitally using image analysis software.
Typically in situ hybridization results are captured by standard cytogenetic studies. Include pertinent medical findings on the requisition with suspected diagnosis and/or indication(s) for testing.
OC Power Word:
6-36 hours for X, 4,18. Overnight-36 hours for 13 and 21
Interpretation is provided with report
88271 (each probe), 88275, 88291
FISH; Fluorescent in situ hybridization