Alpha Globin (HBA1 and HBA2) Deletion/Duplication
Also known as: HBA DD
Use
This test is used for the confirmation of suspected alpha thalassemia or alpha thalassemia trait. It detects common, rare, and novel deletions or duplications in the alpha globin gene cluster, which can result in alpha thalassemia, a condition that affects the synthesis of the hemoglobin alpha-chain. This test is particularly suitable for detecting large deletions or duplications associated with different forms of alpha thalassemia, leading to conditions like Hemoglobin H disease and Hb Bart hydrops fetalis syndrome.
Special Instructions
Not provided.
Limitations
This test is specifically designed to detect large deletions or duplications within the alpha globin gene cluster. It does not detect single exon deletions/duplications based on rearrangement breakpoints, and specific breakpoints of large deletions/duplications cannot be determined. As such, similar-sized mutations may not be distinguishable. Nondeletional mutations within the coding or regulatory regions of the alpha globin cluster genes are not assessed. Errors may occur due to rare sequence variations and individuals carrying both a deletion and a duplication may appear normal.
New York Approved
Methodology
Other
Biomarkers
LOINC Codes
- 31208-2 - Specimen source
- 90040-7 - Alpha globin genes + HS-40 Del+Dup Bld/T
Result Turnaround Time
7-14 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
1 mL
Container
Lavender (EDTA), pink (K2EDTA), or yellow (ACD solution A or B)
Storage Instructions
Refrigerated. Also acceptable: Ambient.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 1 month |
| Frozen | Unacceptable |
Other tests from different labs that may be relevant