DiGeorge/Velo-cardio-facial/Shprintzen/Conotruncal anomaly syndrome, Deletion 22q11.2, TUPLE1, FISH, for Genetic Diagnosis
| WSLH Department: | Cytogenetics |
| WSLH Test Code: | 871F28 |
| Availability: | Monday-Friday 7:45 AM - 4:30 PM, Saturday 7:45 AM - 12:00 PM |
| Turn-around Time: | Approximately 4-6 days, RUSH results for newborns available in approximately 3-5 days |
| Recommended Uses: | Detection of deletion 22q11.2 associated with DiGeorge/Velo-cardio-facial/Shprintzen/Conotruncal anomaly syndrome; phenotypic features include congenital heart disease, cleft palate, immune deficiency, low serum calcium levels. |
| Contraindications: | |
| Additional Tests Performed: |
| Patient Preparations: | |
| Specimen Requirements: | 1-2 ml whole blood collected in sodium heparin vacuum type tube |
| Specimen Handling & Transport: | Store and transport specimens at room temperature (may transport with coolant during hot weather, >85 degrees F). DO NOT FREEZE. The laboratory must receive specimens within 24 hours of collection. |
| Collection Kit/Container: | |
| Collection Instructions: | Draw blood using aseptic techniques into a sterile sodium heparin vacuum type tube. Invert tube to mix. If using larger tubes, draw to full volume to avoid over-treatment with heparin. |
| Unacceptable Conditions: | Blood that is collected in EDTA, sodium citrate, or other anti-coagulants is not acceptable. Blood that is clotted or hemolyzed is not acceptable. Blood must not be frozen. Plasma and serum are not acceptable. |
| Requisition Form: |
Cytogenetics Lab Genetic Diagnosis Form #131
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| Required Information: | Laboratory regulations require the following minimum information to be provided on the requisition form for a specimen to be accepted for testing: Patient name or unique identifier; date and time of collection, patient date of birth and sex, specimen type/site of collection, test request(s), reason for referral, clinician name and UPIN/NPI, and address for reporting results. Please be certain that name/identifier on the form matches that on the specimen label. |
| Results Include: | Number of nuclei examined, percent positive for loss of 22q11.2 (TUPLE1), and the reference range for false positives based on the number of cells with an abnormal signal pattern in 200 control cells. Result written using current International System for Human Cytogenetic Nomenclature (ISCN) and interpretation of results. |
| Limitations: | Very small deletions or point mutations are not detected by this assay. Negative FISH results do not rule out a diagnosis of DiGeorge/Velo-cardio-facial/Shprintzen/Conotruncal anomaly syndrome. |
| Additional Tests Recommended: | Blood chromosome analysis is recommended to look for other causes of the abnormal phenotype. The FISH analysis may be performed as an independent test if chromosome analysis was performed previously. |
| Additional Comments: | If FISH assay is not performed in conjunction with chromosome analysis there is an additional charge for processing the specimen. |
| Methodology: | Fluorescence in situ hybridization performed on metaphase cells using DNA probes (LSI DiGeorge/VCFS Region [Tuple1] Microdeletion Probe/ARSA control; Vysis, Inc) specific for 22q11.2 (TUPLE1, D22S553), simultaneously with a probe for 22q13.3 (ARSA) in the long arm of chromosome 22 as a control. |
| Includes: | FISH analysis of 10 cells for deletion of the TUPLE1 gene in 22q11.2 |
| CPT Code: | 88271, 88273 |
| Price: | For pricing information, please call 608-262-0402. |