G-banded Chromosome Analysis and Karyotyping for Constitutional Abnormalities [UWMC Cytogenetics and Genomics]

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General Information

Lab Name
Lab Code
113
Description

This test detects chromosomal aberrations, including both imbalanced (aneuploidy, deletions, duplications) and balanced (translocations and inversions) rearrangements in the genome at low resolution. This test can also distinguish free from translocation-associated trisomy. Testing is performed by UWMC - Montlake DLMP Cytogenetics and Genomics Laboratories.

Routine study: 15-20 cells evaluated

Family follow-up study: 5 cells evaluated for known familial abnormality

Mosaicism study: 50 cells evaluated

EPIC Ordering:

  • Test Name: Karyotype, Constitutional
  • Order Code: LAB016
  • For orders submitted electronically via Epic, a separate requisition form is not required.
Forms & Requisitions

Cytogenetics Constitutional Test Request Form

Synonyms
Aneuploidy, Down Syndrome, Inversion, Karyotype, Klinefelter Syndrome, LAB016, Monosomy, Mosaicism, Reciprocal Translocation, Robertsonian Translocation, Sex Chromosome Abnormalities, Translocation, Triploidy, Trisomy 13, Trisomy 18, Trisomy 21, Turner Syndrome, XXX, XXY, XYY
Components

Interpretation

Reference Range
Interferences and Limitations

The standard cytogenetic methodology used in this analysis does not routinely detect subtle submicroscopic balanced rearrangements, low-level mosaicism (note that screening of additional cells can be ordered if mosaicism is suspected), or microdeletions and microduplications below the resolution of the banding level. This test will not detect either point mutations or DNA methylation anomalies and other epigenetic events that may be responsible for a clinical phenotype.

Ordering & Collection

Specimen Type
Amniotic Fluid or Cultured Amniocytes, Chorionic Villi, Fetal Tissue, Peripheral Blood, Products of Conception, Skin Biopsy, Umbilical Cord Blood
Collection

Amniotic Fluid:

  • Collect 15-30 mL of fluid obtained under sterile conditions into Corning tissue culture tubes or tubes from a Baxter amniocentesis tray kit. Discard the first 1 mL of fluid or use for af-AFP testing.

Chorionic Villi:

  • Collect up to 40 mg chorionic villi in a sterile flask or tube with sterile tissue culture media (supplied by the lab; Call 206.598.4488).

Peripheral Blood:

  • 10 mL for adults or 1-3 mL for infants in a preservative-free sodium heparin (green top) vacutainer OR in a sterile heparinized syringe.

Cord Blood:

  • 1-3 mL in a preservative-free sodium heparin (green top) vacutainer OR in a sterile heparinized syringe.

Skin biopsies, Products of conception, Fetal tissue:

  • For products of conception, send villi when identifiable. Keep refrigerated. If material is small or unidentifiable, send entire sample. For fetal tissue, send fascia lata, lung, or kidney when possible. Use separate containers and label with contents.
  • Obtain sample under sterile conditions and place in transport media containing antibiotics (e.g. Alpha-MEM media, RPMI). Transport media can be supplied by the lab; call 206.598.4488 to request.
  • If transport media is not available, the following media are acceptable alternatives if shipping time will not exceed 24 hours: lactated Ringer's solution, viral transport medium, or sterile saline.
  • DO NOT USE formaldehyde, formalin, alcohol, or 5% dextrose, or tissue culture medium buffered with bicarbonate.
Forms & Requisitions

Cytogenetics Constitutional Test Request Form

Handling Instructions

Outside Laboratories:

  • Maintain and transport samples at ambient temperature unless otherwise indicated in the Collection section.
  • Sample collection kits are available upon request. Kits include sample collection tubes, transport media (when required), a biohazard bag with absorbent material, a test requisition, and FedEx shipping materials. Contact the lab at 206.598.4488 to request a kit.
  • A completed request form must accompany all orders.
  • Specimens are accepted 24 hrs/day, 7 days/week.
  • Ship to:
    • Cytogenetics and Genomics Laboratory
    • University of Washington Medical Center, Room NW-125
    • 1959 NE Pacific Street
    • Seattle, WA 98195-6100
Quantity
Requested: Varies; refer to Collection information.
Minimum: Varies; refer to Collection information.

Processing

Receiving Instructions

Hold specimen(s) at room temperature.

  • Call Cytogenetics and Genomics Laboratory at 206.598.4489 for pick up. Cytogenetics is staffed on weekends to process specimens.
  • If no answer or after hours, call (206) 598-4488 to leave message.
Misc Sendout

Performance

Lab Department
Frequency
Performed daily. TATs: Amniotic fluid, Chorionic villi 7-14 days. Newborn blood 3-7 days. Adult blood 7-21 days. Fetal tissue, Products of conception, Skin biopsy 14-28 days.
Available STAT?
Yes
Performing Location(s)
Pathology Cytogenetics Laboratory
206-598-4488
Other Locations/Notes

Cytogenetics and Genomics Laboratory

University of Washington Medical Center, Room NW-125
1959 NE Pacific Street
Seattle, WA 98195-6100

  • Ph: (206) 598-4488
  • Fax: (206) 598-2610
  • Email: cytogene@uw.edu

Billing & Coding

Billing Comments

CPTs:

  • Amniotic fluid: 88235, 88267, 88291
  • Chorionic villi: 88235, 88267, 88280, 88285, 88291
  • Tissue (POC, etc.): 88233, 88262, 88291
  • Blood (routine): 88230, 88262, 88291
  • Blood (family follow-up): 88230, 88261, 88291
  • Blood (mosaicism): 88230, 88263, 88291

Prior Insurance Authorization: Contact gpab@uw.edu for details