Benign evaluations

Mayo Clinic’s Metabolic Hematology Laboratory has identified more than 400 hemoglobin variants and described more than 45. The lab’s diagnostic genetic testing results are evaluated by board-certified genetic counselors who specialize in translating genetic information into clinical contexts. Our genetic counselors make their clinical decisions by focusing on the utility and limitations of specific genetic testing methods, familial genetic testing strategies, and genetic variant interpretation, and by identifying potential reproductive risks associated with a test finding.

Key testing

• EEEV1 | Red Blood Cell (RBC) Enzyme Evaluation, Blood
  • A focused evaluation of hemolytic anemias caused by underlying red blood cell (RBC) enzyme defects.
• HAEV1 | Hemolytic Anemia Evaluation, Blood
  • Incorporates all testing related to nonimmune hemolytic anemia, including assays for unstable hemoglobin variants, red blood cell enzyme abnormalities, and red blood cell membrane disorders. It assumes a previous negative direct antiglobulin test (DAT) result.
• HBEL1 | Hemoglobin Electrophoresis Evaluation, Blood
  • A reflexive evaluation for the identification of hemoglobin variants and beta thalassemias. The degree and complexity of testing is determined by the nature of the case, including the rarity of the hemoglobin variants present.
• HGBCE | Hemoglobin Variant, A2 and F Quantitation, Blood
  • Monitors patients with previously confirmed Hb variant.
• MEV1 | Methemoglobinemia Evaluation, Blood
  • Evaluates patients with unexplained cyanosis or when methemoglobinemia or pesticide exposure is suspected.
• RBCME | Red Blood Cell Membrane Evaluation, Blood
  • Evaluates patients for suspected red cell membrane disorders, such as hereditary spherocytosis or hereditary pyropoikilocytosis.
• REVE2 | Erythrocytosis Evaluation, Blood
  • Evaluates patients for hereditary (congenital) causes of erythrocytosis. Symptoms should be long-standing or familial in nature.
• THEV1 | Thalassemia and Hemoglobinopathy Evaluation, Blood and Serum
  • Evaluates patients with unexplained microcytosis, suspected alpha thalassemia, or complex hemoglobinopathy/thalassemia disorders undetectable by electrophoresis alone. This evaluation also detects hemoglobin variants responsible for microcytosis (e.g., hemoglobins E or Lepore).

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Next-generation sequencing assays

Key testing

• NHHA | Hereditary Hemolytic Anemia Gene Panel, Next-Generation Sequencing, Varies
  • Comprehensive panel evaluates genes associated with hereditary (congenital) causes of hemolytic anemia. Symptoms should be long-standing or familial in nature.

Additional testing

• NCDA | Congenital Dyserythropoietic Anemia Gene Panel, Next-Generation Sequencing, Varies
• NCYB | Recessive Congenital Methemoglobinemia, CYB5 and CYB5 Reductase Genetic Analysis, Next-Generation Sequencing, Varies
• NENZ | Red Blood Cell Enzyme Disorders Gene Panel, Next-Generation Sequencing, Varies
• NHEM | Hereditary Erythrocytosis Focused Gene Panel, Next-Generation Sequencing, Varies
• NHEP | Hereditary Erythrocytosis Gene Panel, Next-Generation Sequencing, Varies
• NMEM | Red Blood Cell Membrane Disorders Gene Panel, Next-Generation Sequencing, Varies

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Resources