Identification of Mediterranean beta-thalassemia mutations by reverse dot-blot in Italians and Egyptians.

beta-Thalassemia is a significant public health problem in Egypt where over 1000 of the annual 1.5 million newborns are expected to be affected with this disorder. A preventive program of the disease should be multifaceted with its technical component based on carrier screening and prenatal diagnosis through mutation detection.

Mild elliptocytosis associated with the alpha 34 Arg-->Trp mutation in spectrin Genova (alpha I/74).

We report a new mutation responsible for nonhemolytic hereditary elliptocytosis (HE). The proband displayed an impaired spectrin self-association and an increase of the alpha I 74-kD fragment (alpha I/74 abnormality). The responsible mutation occurred in exon 2 of spectrin alpha-gene: alpha 34 Arg-->Trp (CGG-->TGG), defining spectrin Genova.

Severe poikilocytosis associated with a de novo alpha 28 Arg-->Cys mutation in spectrin.

Severe poikilocytosis was observed in an Italian child. The mutation responsible was a de novo alpha 28 Arg-->Cys substitution (CGT-->TGT) in spectrin, a mutation known to cause hereditary elliptocytosis or hereditary pyropoikilocytosis. In this particular case the severity of the manifestations were accounted for by the occurrence, in trans to the alpha 28 mutation, of the alpha V/41 polymorphism.

Hemoglobin Dallas (alpha 97(G4)Asn-->Lys): functional characterization of a high oxygen affinity natural mutant.

Hemoglobin Dallas, an alpha-chain variant with a substitution of lysine for asparagine at position 97(G4), was found to have increased oxygen affinity (p1/2 = 1 mmHg at pH 7.3 and 20 degrees C), diminished cooperativity (n, the Hill coefficient = 1.7) and reduced Bohr effect (about 50%).