Hemoglobin Louisville (β42 (CD1) Phe→Leu): an unstable variant causing mild hemolytic anemia

A new Spanish family with Hb Louisville

“…The first cases of Hb Louisville were reported by Keeling et al [1971] in a Kentucky family with English-Irish ancestry. Almost simultaneously, the same Hb was described by Bratu et al [1971] as Hb Bucuresti in a Rumanian woman and her daughter.…”

Hemoglobin Okaloosa (β48 (CD7) Leucine → Arginine). AN UNSTABLE VARIANT WITH LOW OXYGEN AFFINITY

“…Buffer composition (19) and ionic strength fiT-6 fT-7 fiT-8 fT-9 fT-10 fiT-11 fT-12A fiT-12B fT-13 fiT-14 fT-15 It is not apparent why substitution of arginine for leucine at position CD7 produces decreased oxygen affinity and increased heat precipitability, but similar abnormalities have been observed in hemoglobins produced by neighboring mutations. Four unstable hemoglobins with decreased oxygen affinity are produced by substitutions at position CD1 (Hammersmith [21], Louisville [3], Bucuresti [22], and Torino [23]). These hemoglobins are quite unstable, and carriers have clinically significant hemolytic anemia.…”

Hemoglobin Cheverly: an Unstable Hemoglobin Associated with Chronic Mild Anemia

“…That other hemoglobin variants in the CD region of the ,8 chain may be associated with mild symptoms is well recognized. Hemoglobin Louisville (Bucuresti), in which leucine replaces phenylalanine at residue 42 (CD 1) of the / 3 chain, represents a substitution by a hydrophobic amino acid residue, and therefore results in relatively minimal impairment of hemeglobin interaction (2,13). Interestingly, patients with Hb Louisville are slightly anemic and form Heinz bodies only after incubation with redox dyes, whereas patients with Hb Bucuresti demonstrate more striking reduction in hemoglobin levels and also exhibit Heinz body formation on initial staining with Nile blue dye.…”