Hemoglobin-LeporeBaltimore, a Third Type of a δβ Crossover (δ50, β86).

A new Lepore-type hemoglobin in a person of Negro descent has been identified. In this person a minor hemoglobin (Hb-Lepore_Baltimore) was detected. An abnormal δβ-chain was isolated and fingerprinted. This hybrid-type protein presumably arose as a consequence of unequal crossing over between the δ and β genes, as was concluded for Hb-Lepore_Boston and Hb-Lepore_Hollandia. In the new Lepore-type hemoglobin described here the crossover could be placed between residues δ⁵⁰ and β⁸⁶. This type of crossover should occur with the highest frequency if crossing over is equally frequent between any nucleotide and if selection favours none of the crossover types. [ABSTRACT FROM AUTHOR]