Hb A(2)-Monreale [Delta 146(Hc3)His -> Arg], A Novel Delta Chain Variant Detected In West Sicily

We report a novel mutation, Hb A(2)-Monreale [delta146(HC3)His-->Arg], detected by cation exchange high performance liquid chromatography in a family from West Sicily. The mutation is due to a CAT --> CGT substitution at codon 146 of the delta-globin gene. The two carriers had reduced levels of normal Hb A(2) (1.1%), but comparable levels (0.9%) of the Hb A(2) variant. Most likely the new variant has the same characteristics as Hb Cochin-Port Royal [beta146(HC3)His-->Arg], that is stable but has a 75% reduction of the Bohr effect. The finding of the new variant increases the genotype heterogeneity of the delta-globin gene in the Mediterranean area, and is relevant to the study and prevention of Cooley's Anemia.