Ordering Recommendation

Molecular confirmation of a suspected structural hemoglobinopathy or beta thalassemia.

Mnemonic
BGSEQ
Methodology

Polymerase Chain Reaction/Sequencing

Performed

Sun-Sat

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: 1 week; Refrigerated: 1 month; Frozen: 6 months

Reference Interval

Normal: This specimen has a normal sequence of the b-globin gene.  No variants 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 variants 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 variants in the HBB gene.
Variants tested:
The complete protein coding sequence with exon/intron boundaries, 5'proximal promoter and untranslated region, 3' polyadenylation signal, and intronic variants c.93-21 (IVS-I-110), c.316-197 (IVS-II-654), c.316-146 (IVS-II-705), c.316-106 (IVS-II-745), and c.316-86_316-85 (IVS-II-765 L1).
Clinical Sensitivity: Up to 97 percent, depending upon ethnicity.
Methodology:
Bidirectional sequencing of the HBB coding regions, intron-exon boundaries, 5' proximal promoter and untranslated region, 3'polyadenylation signal, and intronic variants c.93-21 (IVS-I-110), c.316-197 (IVS-II-654), c.316-146 (IVS-II-705), c.316-106 (IVS-II-745), and c.316-86_316-85 (IVS-II-765 L1).
Analytical sensitivity: 99 percent.
Limitations:
Diagnostic errors can occur due to rare sequence variations. Large deletions, and variants in distal regulatory elements are not detected.

Compliance Statement C: For human genetic inheritable conditions and mutations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

Note
Hotline History
N/A
CPT Codes

81364

Components
Component Test Code* Component Chart Name LOINC
0050578 Beta Globin Full Gene Sequencing 21689-5
2001338 BGSEQ Specimen 31208-2
* 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.
Aliases
  • HBB mutation testing, B Globin gene
Beta Globin (HBB) Gene Sequencing