Beta Globin (HBB) Gene Sequencing
0050578
 
Ordering Recommendation
Genetic test for confirmation of suspected structural hemoglobinopathy or beta thalassemia.
Mnemonic
BGSEQ
Methodology
Polymerase Chain Reaction/Sequencing
Performed
Varies
Reported
14-21 days
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
 
Collect
Lavender (EDTA) or pink (K2EDTA). Also acceptable: 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
Normal: This specimen has a normal sequence of the b-globin gene. No mutations were identified within the b-globin coding region, the intron/exon splice site boundaries or intronic positions IVS-II 654, IVS-II 705, and IVS-II 745. Gene deletions or mutations causing thalassemias or hemoglobinopathies outside of these regions will not be identified.
Interpretive Data
Background Information: Beta Globin (HBB) Sequencing
Characteristics:
Structural hemoglobinopathies or thalassemias (insufficient or absent beta- chain production).
Incidence:
Varies with ethnicity.
Inheritance:
Usually autosomal recessive, infrequently autosomal dominant.
Cause:
Pathogenic mutations i n the HBB gene.
Mutations tested:
The complete protein coding sequence with exon/intron boundaries, proximal promoter, 5' and 3' untranslated regions, and intronic mutations IVS-II-654, IVS-II-705 and IVS-II-745 and the 619del common in the Asian Indian population.
Clinical Sensitivity:
Up to 97 percent, depending upon ethnicity .
Methodology:
Bidirectional sequencing of the HBB coding regions, intron-exon boundaries, proximal promoter, 5' and 3' untranslated regions, and intronic mutations IVS-II-654 , IVS-I I-705 and IVS-II-745. The 619del mutation is detected by PCR followed by gel electrophoresis.
Analytical sensitivity:
99 percent.
Limitations:
Diagnostic errors can occur due to rare sequence variations. Large deletions, other than 619del, and mutations in distal regulatory elements are not detected.

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)
81404
Components
Component Test Code*Component Chart Name
0050578Beta Globin Full Gene Sequencing
2001338BGSEQ 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
  • Beta Thalassemia