Structural and functional studies of hemoglobin J Cala-bria: beta64 (E8) Gly leads to Asp

A hemoglobin of high electrophoretic mobility was detected in a French male suffering from an acute leukemia; this hemoglobin was also present in his family. The variant was unstable and possessed an abnormal beta chain, in which a glycyl residue in position 64 (E8) was replaced by an aspartyl residue. This variant constitutes a new case of Hb J Calabria. Since the substituted E8 residue is in close spatial contact with that at B6, it was of interest to compare the properties of Hb J Calabria with those of other hemoglobins bearing substitutions at the same site.