Hemoglobin A2 Fraction (High-Performance Liquid Chromatography)
This test measures a specific type of hemoglobin (the protein in red blood cells that carries oxygen) called Hemoglobin A2, which is part of the normal breakdown of hemoglobin over time. It helps assess how well your body is producing healthy red blood cells.
["HbA2 helps diagnose and monitor conditions like beta-thalassemia."]
Key facts at a glance
- LOINC
- 55371-9
- Short code
- Hgb A2+E+O MFr Bld
- Synonyms
- Hgb A2+E+O MFr Bld
- Category
- hematology
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why is this test done?
Your healthcare provider may order an HbA2 test if you have symptoms of a blood disorder, such as fatigue, pale skin, or shortness of breath. It’s also used to monitor people with known genetic blood conditions like thalassemia or sickle cell disease. This test helps track how well your red blood cells are functioning over time.
How is the test collected?
A small blood sample is taken from a vein in your arm, usually by a healthcare professional. The blood is then sent to a lab for analysis using a specialized technique called high-performance liquid chromatography (HPLC).
What does the result mean?
HbA2 levels can vary depending on your health condition. Higher levels may indicate certain genetic blood disorders, while lower levels could suggest other health issues or medications affecting red blood cell production. Your results will be compared to standard reference ranges provided by your lab.
What are common reasons for abnormal results?
Abnormally high HbA2 levels are often linked to inherited blood disorders like thalassemia or sickle cell trait. Low levels might be due to anemia, certain medications, or other underlying health conditions. Always discuss your results with your doctor for personalized interpretation.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: HbA2 is a key marker for diagnosing and managing inherited blood disorders. It complements other tests like hemoglobin A1c (HbA1c) by providing insight into the proportion of abnormal hemoglobin variants in your bloodstream, helping tailor treatment plans for conditions like thalassemia or beta-globin disorders.
Short name
HbA2
Frequently asked questions
What does an HbA2 test tell me about my overall health?
How often should I get this test?
Can lifestyle changes affect HbA2 levels?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy