Oxygen Equilibria of Red Cell Hæmolysates of Adult Individuals, Heterozygous for Different Rare Abnormal Hæmoglobins
IN the past few years, oxygen equilibria of various normal and abnormal adult human hæmoglobin types have been studied. No differences were observed between normal Hb-A (&α2β2) and the β-chain abnormalities Hb-S (ref. 1), Hb-C (ref. 2) and Hb-E (ref. 3). Investigations of the isolated Hb-A2' (α2δ2) and its abnormal variant Hb-A2 revealed a considerable increase in oxygen affinity when compared with normal Hb-A (ref. 4). Hb-Lepore, which is composed of normal α-chains and `β' chains being related to the β-chain of Hb-A as well as to the δ-chain of Hb-A2 (ref. 5), showed a high affinity for molecular oxygen similar to that of Hb-A2 (ref. 1). The affinities of the α-chain lacking abnormal hæmoglobin types Hb-H (β4) and Hb-Bart's (γ4) for molecular oxygen were found to be extremely high, while no Bohr effect or hæm-hæm interactions were detectable6,7.