X and Y Aneuploidy Detection, Buccal Smear, FISH
Method Description Describes how the test is performed and provides a method-specific reference
Buccal mucosa cells are analyzed for XX (females) and XY (male) sex chromosome complement by using X and Y centromere probes. These probes are hybridized to interphase cells and visualized by fluorescence microscopy using a process called fluorescence in situ hybridization (FISH). Normal female cells will have 2 orange signals signifying hybridization of the X chromosome probe to both X chromosome centromeres. Normal male cells will have a single orange and a single green signal, signifying hybridization of the X chromosome probe to the X centromere and the Y chromosome probe to the Y chromosome centromere, respectively. The number of individual cells is expressed as a percentage of the total number of interphase cells analyzed. Up to 200 cells will be analyzed for the sex chromosome signal pattern. (Schad CR, Kuffel DG, Wyatt WA, et al: Application of fluorescent in situ hybridization with X and Y chromosome specific probes to buccal smear analysis. Am J Med Genet 1996;66:187-192)
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.
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
Performing Laboratory Location The location of the laboratory that performs the test