MPLNET.com » Test Menu » Trisomy 12 by FISH Client Login | Email | Phone: 1.865.380.9746

Trisomy 12 by FISH

Test Code

F T12

Test Synonyms

+12, CEP 12

Associations

Chronic Lymphocytic Leukemia (CLL)

Methodology

Fluorescence in situ Hybridization (FISH)

Turnaround Time

3-5 days

Specimen Requirements

5mL peripheral blood in sodium heparin
3mL bone marrow in sodium heparin
Fixed cytogenetically prepared cells in sterile centrifuge tube with pellet visible in 3:1, Methanol:Acetic Acid

Specimen Stability
Blood and bone marrow = 4°C to 25°C, specimens are stable up to 72 hours
Fixed cell pellets are stable for years when stored at -28°C to 15°C

Storage & Handling

4°C to 25°C during transit, but specimens may be transported on refrigerated gel packs. Do not allow the gel pack to come in contact with the specimen. Do not freeze. Extreme temperatures should be avoided.

Causes for Rejection

Clotted specimen; Specimen exposed to extreme temperature; Anticoagulant toxic to cells; Insufficient number of cells

Reference Range

In a normal cell, the expected pattern is the two green signal pattern. In a hybridized abnormal cell containing a trisomy of chromosome 12, a three green signal pattern is detected.

Description

Trisomy 12 is among the more common recurring chromosomal
defects in chronic lymphocytic leukemia (CLL). It has been reported in 15–30% of cases and is correlated with atypical morphology. FISH can detect this trisomy in either interphase or metaphase cells.

References
  1. Athanasiadou, Anastasia et al. (2006). Cancer Genetics and Cytogenetics. 168:109-119.