MLAB 1415:Hematology Keri Brophy -Martinez. Chapter 10: The Hemoglobinopathies Part Two. Hemoglobin C Disease. Introduction. Amino acid substitution of lysine for glutamic acid at sixth position of Beta chain ( α 2 β 2 6Glu-Lys ) Is homozygous CC
MLAB 1415:HematologyKeri Brophy-Martinez
Hemoglobin C Disease
Hemoglobin E Disease
Similar to Hb D
Mild, microcytic, hypochromic hemolytic anemia
Many target cells
Electrophoresis shows E band. Normal Hb F, no Hb A
May protect against malaria
Unstable Hemoglobin Variants
Unstable hemoglobins are hemoglobin variants in which amino acid substitutions or deletions have weakened the binding forces that maintain the structure of the molecule.
Instability may cause Hb to denature and precipitate in the red cells as Heinz bodies.
Hemoglobin Variants with Altered Oxygen Affinity
Methemoglobinemia (Hemoglobin M)
5 variants of Hb M which result from single amino acid substitution in the globin chain that stabilizes iron in the ferric form.
Patients have cyanosis, but are otherwise asymptomatic and no treatment is given.
Blood is chocolate brown.
Mild hemolytic anemia.
M band on electrophoresis.
Decreased delivery of oxygen to tissues.
Hb values from normal to 20 g/dL.
Leukocytes and platelets normal.
Normal life span.
Often results in polycythemia.
Increased release of oxygen to tissues.
Patient may become anemic.