USP6 (17p13), Aneurysmal Bone Cyst and Nodular Fasciitis, FISH
Method Description Describes how the test is performed and provides a method-specific reference
Formalin-fixed, paraffin-embedded tissues are cut at 4 microns and mounted on positively-charged glass slides. Five slides are prepared, with 1 to 2 slides stained with hematoxylin and eosin (H and E); the other 3 are left unstained. The selection of tissue and the identification of target areas on 1 of the stained slides are performed by a pathologist. Using the H and E slide as a reference, target areas are etched with a diamond-tipped etcher on the back of the unstained slide. Abnormalities involving USP6 at the 17p13 locus are detected using a FISH break-apart probe (BAP) (Mayo Clinic developed). The probe design consists of DNA derived from bacterial artificial chromosomes (BACs) flanking the USP6 locus. The 5' end is labeled with spectrum orange (R) and the 3' end is labeled with spectrum green (G). The probe set is applied to the appropriate target areas, denatured, and hybridized overnight. Two independent technologists analyze 100 interphase nuclei each (200 total). Normal interphase nuclei show 2F (fusion) signals. Abnormal nuclei will have 1F+1R (> or =10%), 1F+1G (> or =10%), 1R1G (> or =5%), and 1F+1R+1G (> or =5%). The sample is positive if there are > or =10% abnormal cells in 200 cells and is reported out as positive or negative for USP6 rearrangement in International System for Human Cytogenetic Nomenclature. The results are interpreted and reported by a working group pathologist.(Erickson-Johnson MR, Chou MM, Evers BR, et al: Fusion of Non-Muscle Myosin MYH9 to USP6 Oncogene in Nodular Fasciitis, USCAP Abstract #39, 2011; Erickson-Johnson MR, Chou MM, Evers BR, et al: Nodular fasciitis: a novel model of transient neoplasia induced by MYH9-USP6 gene fusion. Lab Invest 2011 Oct;91:1427-1433)
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.
Monday through Friday; 8 a.m.-4:30 p.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
1 week/7 days
Performing Laboratory Location The location of the laboratory that performs the test