Test ID: FRTAL
T-Cell Acute Lymphoblastic Leukemia (T-ALL), FISH
Method Description
Describes how the test is performed and provides a method-specific reference
Identification of deletions of the p16 locus on chromosome 9 is based on a FISH enumeration strategy. Rearrangements of the STIL/TAL1, TRB, MLL, and TRAD locus on 1p32, 7q34, 11q23, and 14q11.2, respectively, are detected using a dual-color, break-apart (BAP) probe strategy. Dual-color, dual-fusion (D-FISH) probe strategies are used to detect t(5;14)(q35;q32), t(9;22)(q34;q11.2), t(10;11)(p13;q14), and in reflex testing when rearrangements of MLL and TRAD gene loci are detected. Amplification of the ABL1 gene on chromosome band 9q34 is detected using a D-FISH probe strategy. For the enumeration and BAP probe sets, 200 interphase nuclei are scored and for the D-FISH probe sets, 500 interphase nuclei are scored. Results for each abnormal probe set are expressed as percent abnormal nuclei. (Unpublished Mayo method)
Day(s) and Time(s) Test Performed
Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Samples processed Monday through Sunday. Results reported Monday through Friday, 8 a.m.-5 p.m. CST.


