Alpha Globin (HBA1 and HBA2) Sequencing and Deletion/Duplication
Also known as: HBA FGA
Use
The test is a comprehensive genetic assay used to detect alpha thalassemia or traits linked with it. Alpha thalassemia is caused by reduced or absent synthesis of the hemoglobin alpha chain, resulting in various clinical presentations. The test utilizes sequencing and deletion/duplication analysis to identify pathogenic variants in the alpha globin gene cluster, which are responsible for the disorder.
Special Instructions
Informed consent for genetic testing is required for patients in New York. Genetic consultation is recommended based on clinical findings and family history. Counseling and consent forms are advised for genetic testing purposes. This test is also approved for use in New York State.
Limitations
The test may not detect all regulatory region variants or variants in alpha globin cluster genes beyond HBA1 and HBA2. It may fail to identify phase of sequence variants and specific breakpoints of large deletions. There is a risk of diagnostic errors due to rare sequence variations. Sequencing of HBA2-HBA1 fusion genes will not be performed and may miss significant variants.
New York Approved
Methodology
NGS
Biomarkers
LOINC Codes
- 66746-9
- 35474-6
Result Turnaround Time
14-21 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
2 mL
Container
Lavender (EDTA), pink (K2EDTA), or yellow (ACD solution A or B)
Storage Instructions
Refrigerated
Causes for Rejection
Frozen specimens
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 1 month |
| Frozen | unacceptable |