The detection and diagnosis of hemoglobin A2′ by high-performance liquid chromatography

Robert Van Kirk, Linda M. Sandhaus, James D. Hoyer

Research output: Contribution to journalArticlepeer-review

26 Scopus citations


Hemoglobin (Hb) A2′ is a hematologically silent variant of HbA2 that is detected easily by high-performance liquid chromatography (HPLC), where it elutes in the S window. Our purposes were to define diagnostic criteria for the HbA2′ trait using the Variant II (Bio-Rad, Hercules, CA) and to determine the prevalence of HbA 2′ in a metropolitan patient population. All Hb screens (N = 5,862) performed during a 26-month period were reviewed for new hemoglobinopathies. We identified 57 cases of HbA2′ trait, making it the fourth most prevalent Hb variant detected in this population after HbS, HbC, and β-thalassemia minor. For HbA2′ trait cases, the mean HbA2 level was 1.7% (SD, 0.17%), and the mean HbA 2′ level was 1.3% (SD, 0.18%). Six possible HbA 2′/β-thalassemia double heterozygotes were identified, for whom the sum of the HbA2 and HbA2′ exceeded 4% of total Hb. Hb variants that might interfere with detection of HbA 2′ include HbS, glycosylated HbC, and HbG2. Diagnostic criteria proposed for the HbA2′ trait by HPLC are HbA2 of 2% or less, S window peak of 1% to 2%, no previous diagnosis of HbS, and absence of HbG and HbC.

Original languageEnglish (US)
Pages (from-to)657-661
Number of pages5
JournalAmerican journal of clinical pathology
Issue number5
StatePublished - May 2005


  • HbA
  • HbA′
  • Hemoglobin electrophoresis
  • Hemoglobinopathy
  • High-performance liquid chromatography
  • Isoelectric focusing
  • β-Thalassemia

ASJC Scopus subject areas

  • Pathology and Forensic Medicine


Dive into the research topics of 'The detection and diagnosis of hemoglobin A2′ by high-performance liquid chromatography'. Together they form a unique fingerprint.

Cite this