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HelpTest Code XYMF Known 45,X, Mosaicism Reflex Analysis, FISH, Whole Blood
Useful For
Detecting sex chromosome mosaicism in patients with a 45,X karyotype
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| _I099 | Interphases, 25-99 | No, (Bill Only) | No |
| _I300 | Interphases, >=100 | No, (Bill Only) | No |
| _IL25 | Interphases, <25 | No, (Bill Only) | No |
| _PADD | Probe, +1 | No, (Bill Only) | No |
| _PB02 | Probe, +2 | No, (Bill Only) | No |
| _PB03 | Probe, +3 | No, (Bill Only) | No |
| _PBCT | Probe, +2 | No, (Bill Only) | No |
Testing Algorithm
Appropriate ancillary probes may be performed at consultant discretion to render comprehensive assessment. Any additional probes will have the results included within the final report and will be performed at an additional charge.
Special Instructions
Method Name
Fluorescence In Situ Hybridization (FISH)
Reporting Name
Known 45,X Mosaicism Reflex, FISHSpecimen Type
Whole bloodOrdering Guidance
This test does not detect other chromosomal or structural anomalies and is intended to be ordered after a complete chromosome analysis.
Shipping Instructions
Advise Express Mail or equivalent if not on courier service.
Necessary Information
A reason for testing must be provided. The laboratory will not reject testing if this information is not provided however an applicable indication for testing may be entered by Mayo Clinic Laboratories. Appropriate testing and interpretation may be compromised or delayed.
Specimen Required
Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA) or yellow top (ACD)
Specimen Volume: 4 mL
Collection Instructions
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
3. Other anticoagulants are not recommended and are harmful to the viability of the cells.
4. Cord blood is acceptable
Additional Information:
1. If the specimen does not grow in culture, you will be notified within 7 days of receipt.
2. Specimen cannot be frozen.
Specimen Minimum Volume
2 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Whole blood | Ambient (preferred) | ||
| Refrigerated | |||
Reference Values
An interpretive report will be provided.
Interpretation
An XX clone is confirmed when at least 1.0% of cells display with 2 X chromosome signals. An XY clone is confirmed when at least 0.6% of cells display a 1 X and 1 Y signal pattern.
Phenotypic females with a 45,X/46,XX karyotype have no increased risk of gonadoblastoma and generally have a more moderate expression of Turner syndrome features than phenotypic females with a nonmosaic 45,X karyotype. The presence of a Y chromosome confers increased risk of gonadoblastoma.
Clinical Reference
1. Canto P, Kofman-Alfaro S, Jiminez AL, et al. Gonadoblastoma in Turner syndrome patients with nonmosaic 45,X karyotype and Y chromosome sequences. Cancer Genet Cytogenet. 2004;150(1):70-72
2. Wiktor A, Van Dyke DL. FISH analysis helps identify low-level mosaicism in Ullrich-Turner syndrome patients. Genet Med. 2004;6(3):132-135
3. Sybert VP, McCauley E. Turner syndrome. N Engl J Med. 2004;351:1227-1238
4. Gravholt CH, Andersen NH, Conway GS, et al. Clinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting. Eur J Endocrinol. 2017;177(3):G1-G70
Day(s) Performed
Monday through Friday
Report Available
7 to 9 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
88271x2, 88291-DNA probe, each (first probe set), Interpretation and report
88271x2-DNA probe, each; each additional probe set (if appropriate)
88271x1-DNA probe, each; coverage for sets containing 3 probes (if appropriate)
88271x2-DNA probe, each; coverage for sets containing 4 probes (if appropriate)
88271x3-DNA probe, each; coverage for sets containing 5 probes (if appropriate)
88274 w/modifier 52-Interphase in situ hybridization, <25 cells, each probe set (if appropriate)
88274-Interphase in situ hybridization, 25 to 99 cells, each probe set (if appropriate)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| XYMF | Known 45,X Mosaicism Reflex, FISH | 87436-2 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 51844 | Result Summary | 50397-9 |
| 51846 | Interpretation | 69965-2 |
| 54537 | Result | 62356-1 |
| CG668 | Reason for Referral | 42349-1 |
| 51847 | Specimen | 31208-2 |
| 51848 | Source | 31208-2 |
| 51849 | Method | 85069-3 |
| 54451 | Additional Information | 48767-8 |
| 55279 | Disclaimer | 62364-5 |
| 51850 | Released By | 18771-6 |
Forms
New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available: