Useful for diagnosis of congenital chromosome abnormalities, including aneuploidy, structural abnormalities, and balanced rearrangements
This test is not appropriate for detecting acquired chromosome abnormalities. If this test is ordered with a reason for referral indicating a hematologic disorder, the test will be cancelled and Chromosome Analysis, Hematologic Disorders, Blood will be performed as the appropriate test.
A chromosomal microarray study (Chromosomal Microarray, Congenital, Blood) is recommended as the first-tier test (rather than a congenital chromosome study) to detect clinically relevant gains or losses of chromosomal material for individuals with multiple anomalies not specific to well-delineated genetic syndromes, individuals with apparently nonsyndromic developmental delay or intellectual disability, and individuals with autism spectrum disorders.
Specimen Type
Whole Blood
Specimen Requirements
Sodium Heparin (Green Top)
Alternate Specimen Type
Cord Blood
Specimen Collection / Processing Instructions
Invert several times to mix blood
Other anticoagulants are not recommended and are harmful to the viability of the cells
Label specimen as either whole blood or cord blood as appropriate
Minimum Sample Volume
2 mL
Required Information
Provide a reason for referral with each specimen. The laboratory will notreject testing if this information is not provided, but appropriate testing and interpretation may be compromised or delayed
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.
Limitations
This test is not appropriate for acquired hematologic disorders, including the following malignancies: chronic myelocytic leukemia, acute myelocytic leukemia, acute lymphocytic leukemia, chronic lymphocytic leukemia, lymphoma, and leukemia
This test is not appropriate as a first-tier test for detecting gains or losses of chromosomal material for individuals with intellectual disability, mental retardation, developmental delay, autism, dysmorphic features, birth defects, behavior disorders, learning disability, or cognitive impairment
Interfering factors:
Cell lysis caused by forcing the blood quickly through the needle
Use of an improper anticoagulant or improperly mixing the blood with the anticoagulant
Excessive transport time
Inadequate amount of blood may not permit adequate analysis
Improper packaging may result in broken, leaky, and contaminated specimen during transport
Exposure of the specimen to temperature extremes (freezing or > 30 degrees C) may kill cells and interfere with attempts to culture cells
Methodology
Cell Culture with Mitogens followed by Chromosome Analysis
Estimated TAT
10 days
Testing Schedule
Monday-Friday
Retention
28 days
CPT Code(s)
88230, 88291- Tissue culture for Lymphocytes, Interpretation and report
88262 w/modifier 52-Chromosome analysis less than15 cells (if appropriate)
88262 - Chromosome analysis with 15 to 20 cells (if appropriate)
88262, 88285-Chromosome analysis with greater than 20 cells (if appropriate)
88280 - Chromosome analysis, greater than 2 karyotypes (if appropriate)
