Hb F-Sassari: a novel G gamma variant with a threonine residue at position gamma 75, characterized by mass spectrometric techniques

The cord blood sample of a Caucasian newborn contained about 40% of an abnormal fetal hemoglobin. The mutated gamma chain was isolated using reversed phase high performance liquid chromatography and characterized by means of electrospray and fast atom bombardment mass spectrometric techniques as a G gamma-globin variant with an Ile-->Thr substitution at position gamma 75. The variant chain shows the same structure as the previously described Hb F-Charlotte that was demonstrated to be an A gamma variant with an Ile-->Thr substitution at position gamma 75 and an additional Ala-->Gly substitution at gamma 136.