Ordering Recommendation
Determine the number of copies of the RHD gene. Does not identify or distinguish between partial and weak RHD genotypes. A fetal sample is required for determination of fetal RHD genotype.
Mnemonic
Methodology
Polymerase Chain Reaction/Fluorescence Monitoring
Performed
Varies
Reported
2-7 days
New York DOH Approval Status
Specimen Required
Fetal genotyping: Amniotic fluid
OR Cultured amniocytes: Two T-25 flasks at 80 percent confluency.
OR cultured CVS: Two T-25 flasks at 80 percent confluency.
If the client is unable to culture, order test Cytogenetics Grow and Send (ARUP test code 0040182) in addition to this test and ARUP will culture upon receipt (culturing fees will apply). If you have any questions, contact ARUP's Genetics Processing at 800-522-2787 ext. 3301.
WITH maternal cell contamination specimen (see Remarks): Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Parental genotyping: Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Amniotic fluid: Transport 10 mL amniotic fluid in a sterile container. (Min: 5 mL)
Cultured amniocytes AND cultured CVS: Transport two T-25 flasks at 80 percent confluency filled with culture media. Backup cultures must be retained at the client's institution until testing is complete.
Maternal cell contamination specimen: Transport 3 mL whole blood (Min: 1 mL)
Whole blood (parental genotyping): Transport 3 mL whole blood. (Min: 1 mL)
Amniotic fluid, cultured amniocytes and cultured CVS: CRITICAL ROOM TEMPERATURE. Must be received within 48 hours of shipment due to lability of cells.
Whole blood or maternal cell contamination specimen: Refrigerated.
Frozen specimens in glass collection tubes.
Maternal specimen is recommended for proper test interpretation if contamination of the fetal specimen from the mother is suspected. Order Maternal Cell Contamination. Patient History Form is available on the ARUP website or by contacting ARUP Client Services.
Amniotic fluid, cultured amniocytes and cultured CVS Fetal Specimen: Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
Whole blood or maternal cell contamination specimen: Ambient: 72 hours; Refrigerated: 1 week; Frozen: 1 month
Reference Interval
By report
Interpretive Data
Refer to report
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the U.S. Food and Drug Administration. This test was performed in a CLIA- certified laboratory and is intended for clinical purposes.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
Laboratory Developed Test (LDT)
Note
Whole blood is acceptable for paternal specimens.
Hotline History
Hotline History
CPT Codes
81403
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
0050422 | RhD Gene (RHD) Copy Number | 35465-4 |
0051369 | RhD Gene (RHD) Copy Number Specimen | 66746-9 |
Aliases
- RHD Gene
- RHD genotyping