Two new (G)gamma chain variants: Hb F-Clamart [gamma 17(A14)Lys -> Asn] and Hb F-Ouled Rabah [gamma 19(B1)Asn -> Lys]

Two new fetal hemoglobin variants affecting the (G)gamma chain are reported . Hb F-Clamart was found during investigation of a French newborn who prese nted with a mild microcytemia. The second variant was found during neonatal screening for hemoglobinopathies of 30,000 babies from a population-at-ris k living in the Paris region. It was named Hb F-Ouled Rabah because its str uctural modification and ethnic distribution is similar to that of Hb D-Oul ed Rabah [beta 19(B1)Asn-->Lys]. Hb F-Ouled Rabah is clinically silent and occurs at a frequency of cn. 0.1% in newborns originating from Maghreb. Str uctural characterization of both variants was done by protein chemistry met hods, including amino acids analysis and mass spectrometry.