Chromosomal Microarray, Autopsy, Products of Conception, or Stillbirth
Use
This test is useful for prenatal diagnosis of copy number changes (gains or losses) across the entire genome. It assists in diagnosing chromosomal causes for fetal death and determining the recurrence risk of future pregnancy losses. The test determines the size, precise breakpoints, and gene content of abnormalities detected by other methods such as conventional chromosome and FISH studies. It also helps assess regions of homozygosity related to uniparental disomy or identical by descent, providing crucial information in cases of unbalanced chromosomal rearrangements appearing balanced at the conventional resolution level.
Special Instructions
Maternal blood is recommended at the time of test ordering to rule out maternal cell contamination. If maternal blood is not received, maternal contamination cannot be excluded. This test does not detect balanced chromosome rearrangements and is not designed to detect low-level mosaicism. For formalin-fixed, paraffin-embedded specimens, the test will be canceled and an appropriate test will be performed instead. Inform the laboratory if the pregnancy involves an egg donor or gestational carrier.
Limitations
This test does not detect all types and instances of uniparental disomy, low-level mosaicism, point alterations, small deletions, or insertions below the assay's resolution, nor does it identify epigenetic changes. It may reveal incidental findings unrelated to the original referral, requiring studies of additional family members to interpret results. Limitations include challenges in classifying copy number changes due to limited available data and issues related to structural information on aberrations detected.
New York Approved
Methodology
Microarray (SNP Array)
Biomarkers
LOINC Codes
- 94087-4
- 86611-1
- 62356-1
- 62378-5
- 62357-9
- 42349-1
- 31208-2
- 48002-0
- 48767-8
- 18771-6
- 85069-3
Result Turnaround Time
10-25 days
Related Documents
For more information, please review the documents below
Specimen
Other
Volume
1 cm(3) of placenta and 1 cm(3) biopsy specimen of muscle/fascia from the thigh
Minimum Volume
Not provided
Container
Sterile container with sterile Hank's solution, Ringer's solution, or normal saline
Collection Instructions
Attempt to identify and send only fetal tissue for analysis. If a fetus cannot be identified, collect 50-mg villus material or tissue appearing to be of fetal origin. Do not send the entire fetus or large volumes of tissue.
Storage Instructions
Do not use alcohol or iodine preparations for cleaning biopsy site, and use an antiseptic soap. Biopsy specimens are best taken by punch biopsy to include full thickness of dermis.