Sign in →

Test Code XYMF Known 45,X, Mosaicism Reflex Analysis, FISH, Whole Blood

Genetics Test Information

This test is only appropriate to detect low levels of sex chromosome mosaicism when a nonmosaic 45,X karyotype has been observed.

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

Specimen Type

Whole blood


Ordering 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 

Reject Due To

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Reference Values

An interpretive report will be provided.

Day(s) Performed

Monday through Friday

Report Available

7 to 9 days

Specimen Retention Time

4 weeks

Performing Laboratory

Mayo Clinic Laboratories in Rochester

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)