Home
HelpTest ID A2F Hemoglobin A2 and F, Blood
Useful For
Assisting in the diagnosis of beta-thalassemia
Quantitating the percent of hemoglobin F (Hb F) present
Assisting in the diagnosis of disorders with elevated levels of Hb F
Special Instructions
Method Name
Cation Exchange/High-Performance Liquid Chromatography (HPLC)
Reporting Name
Hemoglobin A2 and FSpecimen Type
Whole Blood EDTAContainer/Tube:
Preferred: Lavender top (EDTA)
Acceptable: ACD, heparin
Specimen Volume: 3 mL
Collection Instructions:
1. Submit fresh specimen.
2. Do not transfer blood to other containers.
Additional Information: Patient's age is required.
Forms:
1. Thalassemia/Hemoglobinopathy Patient Information (T358) in Special Instructions
2. If not ordering electronically, complete, print, and send a Benign Hematology Test Request Form (T755) with the specimen (http://www.mayomedicallaboratories.com/it-mmfiles/benign-hematology-test-request-form.pdf)
Specimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole Blood EDTA | Refrigerated | 7 days |
Clinical Information
Hemoglobin F (Hb F), composed of 2 alpha and 2 gamma globin chains, is the normal hemoglobin of the fetus and newborn. Normally in the second trimester, gamma chain production (and Hgb F levels) decrease and beta chain production increases, resulting in increasing levels of hemoglobin A (Hb A), the major normal adult hemoglobin (2 alpha and 2 beta globin chains). Hemoglobin A2 (Hb A2) (2 alpha and 2 delta globin chains) also comprises a small amount (<3.3%) of hemoglobin normally found in adults. Hb A2 values at birth are <1%.
Reference Values
HEMOGLOBIN A2
1-30 days: 0.0-2.1%
1-2 months: 0.0-2.6%
3-5 months: 1.3-3.1%
≥6 months: 2.0-3.3%
HEMOGLOBIN F
1-30 days: 22.8-92.0%
1-2 months: 7.6-89.8%
3-5 months: 1.6-42.2%
6-8 months: 0.0-16.7%
9-12 months: 0.0-10.5%
13-17 months: 0.0-7.9%
18-23 months: 0.0-6.3%
≥24 months: 0.0-0.9%
Cautions
Hemoglobin F (Hb F) is elevated in newborns, reaching adult levels by 12 months.
Hb F is commonly increased to as much as 5% to 10% in normal pregnancy.
Slight elevation in hemoglobin A2 may also occur in hyperthyroidism or when there is deficiency of vitamin B12 or folate.
Day(s) Performed
Monday through Saturday; 7 a.m. and 1 p.m.
Report Available
Same day/1 dayPerforming Laboratory
Mayo Medical Laboratories in Rochester
Test Classification
This test has been modified from the manufacturer’s instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
83021