[Structural variants in hemoglobin occurring in the Czech Republic]

Area of Science:

• Hematology
• Molecular Genetics
• Clinical Medicine

Background:

• Review of diagnosed structural hemoglobin variants in the Czech Republic.
• Focus on unstable hemoglobin variants and their clinical presentation.
• Introduction of novel hemoglobin variants identified within the country.

Observation:

• Hb-Hradec Králové (Hb-HK) is a newly detected unstable variant, challenging traditional diagnosis.
• Hb-HK instability leads to thalassaemic features and Heinz body formation.
• Hb-Olomouc, a high-oxygen-affinity variant, causes erythrocytosis in familial cases.
• Hb-M Milwaukee presents with hemolysis and Heinz bodies rather than cyanosis.

Findings:

• Seven structural hemoglobin variants identified, with unstable types being most frequent.
• Hb-Hradec Králové (alpha 2 beta 2 115 (G17) Ala-Asp) requires molecular genetic diagnosis.
• Hb-Olomouc (alpha 2 beta 2 86 (F2) Ala-Asp) is associated with erythrocytosis.
• Hb-M Milwaukee (alpha 2 beta 2 67 (E11) Val-Glu) manifests as hemolysis.

Implications:

• Highlights the need for advanced diagnostic methods for unstable hemoglobinopathies.
• Suggests potential for novel therapeutic targets for hemoglobin variants.
• Underscores the importance of molecular diagnostics in identifying rare hemoglobin disorders.
• Provides insights into the clinical spectrum of hemoglobin variants in a specific geographic region.