Beta Globin (HBB) HbS, HbC, and HbE Mutations
0051421
 
Ordering Recommendation
Order to confirm suspected HbS, HbC, and HbE mutations.
Mnemonic
HB SCE
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
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).  
Specimen Preparation
Transport 3 mL whole blood. (Min: 1 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
 
Remarks
 
Stability
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable  
Reference Interval
By report
Interpretive Data
Background information for Beta Globin (HBB) HbS, HbC, & HbE Mutations:
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 percent of sickle cell disease in the United States (1 in 2000 individuals). Carrier frequency of HbS is 8-10 percent 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 percent for sickle cell disease; other hemoglobinopathies vary depending upon patient's ethnicity.
Methodology:
PCR and fluorescence resonance energy transfer.
Analytic Sensitivity:
Greater than 99 percent.
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.

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
Components
Component Test Code*Component Chart Name
0051423Beta Globin Gene Allele 1
0051424Beta Globin Gene Allele 2
0051425Beta Globin (HbS,C,E) Interpretation
2001314Beta Globin (HbS, C, E) 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, contact interface support at interface.support@aruplab.com.
Cross References