Microarray testing is available on fresh specimens for suspected hematologic malignancies, constitutional abnormalities, and pregnancy loss indications. Testing is performed by Genetics Associates, Inc. using an enhanced SNP microarray with over 2.6 million SNP and non-polymorphic markers across the genome for detection of copy number variants (deletions, duplications, and amplifications) and copy-neutral loss of heterozygosity. Balanced rearrangements, including translocations and inversions, are not detectable by this method. Testing may not reliably detect abnormalities present in less than 20% of the cells tested.
This test provides genome-wide characterization of chromosomal imbalances with higher resolution than conventional cytogenetics and FISH. Testing may be performed on blood, bone marrow, or products of conception (POC) to obtain a detailed description of breakpoints and unidentified material in abnormal karyotypes, for detecting abnormalities in samples with normal karyotype, and for use after cytogenetics failure due to lack of growth or inadequate metaphases.
- Peripheral blood: 2-5 mL in EDTA tube
- Bone marrow: 2-5 mL in EDTA tube
- Products of conception (fresh tissue, with or without cytogenetics):
- Tissue order of preference: Chorionic villi, placenta or placental membrane, known fetal tissue (especially lung, kidney, thymus, skin).
- Quantity and handling: Please send at least 30-100 mg villi or 0.5 -1 cm3 fresh tissue(s) to our Nashville, TN laboratory (see Contact page for address). Place tissue in RPMI. Tissues placed in formalin are unacceptable. Note type of tissue(s) sent on the test requisition and whether it is fetal in origin or mixed maternal/fetal.
- Note: Please exclude biopsy needles, blades, and other foreign objects from transport tubes. These can compromise specimen viability and yield, and create hazards for employees.
Use cold pack for transport, making sure cold pack is not in direct contact with specimen. Ship same day as drawn whenever possible.