Gamma-Globin Full Gene Sequencing
Use
This test is useful as an adjunct to abnormal results detected by hemoglobin electrophoresis testing. It assists in the diagnosis of nondeletional hereditary persistence of fetal hemoglobin (HPFH), identification of abnormal gamma chain variants such as unstable, high- or low-oxygen affinity, or M hemoglobins, and predicting the severity of a coinherited sickling disorder. It is also relevant for evaluating unexplained neonatal anemia, cyanosis, or hyperbilirubinemia.
Special Instructions
Not provided.
Limitations
This test cannot be used in isolation to confirm or exclude hemoglobin conditions. Large deletions, crossover events, or other variants may not be detected, and sequencing cannot distinguish between alleles in cis or trans. Molecular results should be correlated with electrophoretic, protein data, and/or family studies for accurate diagnosis.
New York Approved
Methodology
PCR-based (Sanger)
Biomarkers
LOINC Codes
- 95795-1 - HBG1 + HBG2 Full Mut Anl Bld/T Seq
- 50397-9 - Mol dx interp Bld/T Ql
- 59466-3 - Hematologist review
Result Turnaround Time
10 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
4 mL
Minimum Volume
1 mL
Container
Lavender top (EDTA) or Yellow top (ACD)
Collection Instructions
Invert several times to mix blood. Send whole blood specimen in the original tube. Do not aliquot.
Causes for Rejection
Moderately to severely clotted specimens, bone marrow, paraffin-embedded tissue, frozen tissue, methanol-acetic acid-fixed pellets.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 30 days |