Beta Globin (HBB) HbS, HbC, and HbE Mutations, Fetal
0051422
Ordering Recommendation
Genetic test on fetal samples for prenatal detection of HbS, HbC, and HbE mutations.
Mnemonic
HB SCE FE
Methodology
Polymerase Chain Reaction/Fluorescence Resonance Energy Transfer
Performed
Tue, Thu
Reported
7-10 days
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
 
Collect
Fetal Specimen: Two T-25 flasks at 80% confluency of cultured amniocytes. If the client is unable to culture amniocytes, this can be arranged by contacting ARUP Client Services at (800) 522-2787. Or amniotic fluid.
AND Maternal Cell Contamination Specimen:
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).  
Specimen Preparation
Cultured Amniocytes: Fill flasks with culture media. Transport two T-25 flasks at 80% confluency of cultured amniocytes. Backup cultures must be retained at the client's institution until testing is complete.
OR Amniotic Fluid:
Transport 10 mL unspun fluid. (Min: 5 mL)
AND Maternal Cell Contamination Specimen:
Transport 3 mL whole blood. (Min: 1 mL)  
Storage/Transport Temperature
Cultured Amniocytes: CRITICAL ROOM TEMPERATURE. Must be received within 48 hours of shipment due to liability of cells.
Amniotic fluid:
Room temperature.
Maternal Cell Contamination Specimen:
Room temperature.  
Unacceptable Conditions
 
Remarks
Maternal specimen is recommended for proper test interpretation. Order Maternal Cell Contamination. Patient History Form is available on the ARUP Web site or by contacting ARUP Client Services.  
Stability
Fetal Specimen: Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
Maternal Cell Contamination Specimen
: Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable  
Reference Interval
By report
Interpretive Data
Background information for Beta Globin (HBB) HbS, HbC and HbE Mutations, Fetal:
Characteristics:
Sickle cell disease results in vascular occlusion and tissue ischemia, and acute or chronic organ dysfunction. Milder forms present with hemolytic anemia.
Incidence:
Sickle cell affects 1 in 250-600 African-Americans. HbS causes 60 to 70% of sickle cell disease in the United States (1 in 2000 individuals). Carrier frequency of HbS is 8-10% in African-Americans. HbS is common in sub-Saharan Africa, India, and the Middle East. HbC is common in West Africa. HbE is common in Southeast Asia.
Inheritance:
Autosomal recessive.
Cause
: Beta globin gene (HbB) missence mutations. The three detected mutations, HbS, HbC, and HbE, have one amino acid change in the beta globin chain. While HbS and HbC result in abnormal beta chain structure, the HbE mutation affects splicing efficiency, resulting in decreased amounts of beta chain.
Mutations Tested:
c.19G>A (HbC), c.20A>T (HbS), c.79G>A (HbE).
Clinical Sensitivity:
Greater than 70% for sickle cell disease; other hemoglobinopathies vary depending upon patient's ethnicity.
Methodology:
PCR and fluorescence resonance energy transfer.
Analytic Sensitivity:
Greater than 99%.
Limitations:
Mutations other than c.19G>A (HbC), c.20A>T (HbS), c.79G>A (HbE) will not be detected. Diagnostic errors can occur due to rare sequence variations.

For quality assurance purposes, ARUP Laboratories will confirm the above result at no charge following delivery. Order Confirmation of Fetal Testing and include a copy of the original fetal report (or the mother's name and date of birth) with the test submission. Please contact an ARUP genetic counselor at (800) 242-2787 extension 2141 prior to specimen submission.

This test is performed pursuant to an agreement with Roche Molecular Systems, Inc.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

See Compliance Statement C: www.aruplab.com/CS
Note
CPT Code(s)
81401;
Fetal Cell Contamination (FCC): 81265;
Components
Component Test Code*Component Chart Name
0050548Maternal Cell Contamination, Fetal Spec
0050612Maternal Cell Contam, Maternal Spec
0051423Beta Globin Gene Allele 1
0051424Beta Globin Gene Allele 2
0051425Beta Globin (HbS,C,E) Interpretation
0051427Beta Globin (HbS, C, E) Fetal Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Cross References
  • Fetal HbS, HbC, HbE mutation testing