RhD Gene (RHD) Copy Number, Fetal
Also known as: RHD FE
Use
This test is used to determine fetal RHD copy number(s) and assess the risk of alloimmune hemolytic disease. It is particularly helpful in predicting the fetal RhD phenotype based on the detection of RhD alleles, which can forecast the risk of hemolytic disease of the fetus and newborn if the mother is sensitized to the RhD antigen.
Special Instructions
Consent forms are required for genetic testing, especially for New York patients. Clients unable to culture samples must order test Cytogenetics Grow and Send for culturing fees. Testing must be completed within a specified timeframe post-sample collection due to the lability of cells.
Limitations
This test does not identify or distinguish between partial and weak RHD genotypes. There is potential for false-negative results due to bloody amniotic fluid specimens caused by maternal cell contamination. Diagnostic errors may also occur due to rare sequence variations or specificity compromises by variants in primer sites.
New York Approved
Methodology
PCR-based (Fragment Analysis)
Biomarkers
LOINC Codes
- 59266-7
- 66746-9
- 31208-2
- 50398-7
Result Turnaround Time
2-7 days
Related Documents
For more information, please review the documents below
Specimen
Amniotic Fluid
Volume
10 mL
Minimum Volume
5 mL
Container
sterile container
Storage Instructions
Transport in critical room temperature.
Causes for Rejection
Frozen specimens in glass collection tubes.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 48 hours |
| Frozen | Unacceptable |