Hemoglobin A2
Hemoglobin A2 (HbA2) is a minor adult hemoglobin variant. It makes up roughly 2–3% of total hemoglobin in healthy adults, with the bulk being hemoglobin A. The percentage is reported alongside other hemoglobin types in specialized panels.
Why it matters: An elevated HbA2 percentage is a feature seen in beta-thalassemia trait — an inherited variation in how hemoglobin chains are produced. The number is one part of a hemoglobin-pattern review, not interpreted in isolation.
May increase with:
May decrease with:
What is Hemoglobin A2?
Hemoglobin A2 (HbA2) is a minor adult hemoglobin variant. It makes up roughly 2–3% of total hemoglobin in healthy adults, with the bulk being hemoglobin A. The percentage is reported alongside other hemoglobin types in specialized panels.
What might a high or low Hemoglobin A2 mean?
An elevated HbA2 percentage is a feature seen in beta-thalassemia trait — an inherited variation in how hemoglobin chains are produced. The number is one part of a hemoglobin-pattern review, not interpreted in isolation.
What can affect Hemoglobin A2?
It may be higher with: Beta-thalassemia, Iron deficiency. It may be lower with: Hemolytic anemia.
Track your Hemoglobin A2 over time
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