Call 1-800-473-9411 to speak with our team of laboratory genetic counselors for questions or additional information.
Robin Fletcher, MS, CGC
Falecia Thomas, MS, CGC
Alex Finley, MS, CGC
Disorders of Sexual Development: FISH Panel, Rule Out Mosaic (Buccal) (includes SRY/Xcen & X/Y dual assay probes)
Key Information
Lab:
TAT:
28 days
Price:
$884
CPT Code(s):
88275x2, 88271x3, 88291
Test Code:
CBSM
Disorders of Sexual Development: FISH Panel, Rule Out Mosaic (Buccal) (includes SRY/Xcen & X/Y dual assay probes)
FISH analysis for Disorders of Sexual Development is a cytogenetic test used to identify deletions or duplications in the centromeric regions of the X chromosome, Yq, as well as SRY. This test is intended for patients with ambiguous genitalia or suspected sex reversal.
Please note the standard turnaround time is 28 days, but is reduced to 4 days for infants.
Technical Information
Fluorescence in situ hybridization is a molecular cytogenetic technique in which fluorescently labeled DNA probes are hybridized to metaphase spreads or interphase nuclei. Applications include identification of structurally abnormal chromosomes, including identification of marker chromosomes, detection of very small deletions (microdeletions), and rapid detection of Down syndrome and other numerical chromosome abnormalities; and the rapid detection of sex chromosomes and the SRY gene.
FISH should be used in conjunction with G-banded chromosome analysis. FISH is performed upon request when a specific numerical or structural abnormality or microdeletion is suspected. FISH is also utilized to confirm microdeletions identified during high resolution chromosome analysis and to aid in identification of abnormal chromosomes.
The routine DSD FISH panel on buccal assess SRY, Xcen, and Yq using interphase FISH on a count of 500 cells. Y centromere is not probed.
Specimen Requirements
FISH analysis on buccal samples requires a kit provided by the Greenwood Genetic Center. Buccal cells are collected by brush and smeared onto a microscope slide using the kit’s included instructions. Contact the lab to request a test kit. Saliva is not accepted for this test.
Transport Instructions
Return the labeled slides in the provided packaging via USPS or other transport service at room temperature.