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This report is concerned with the evaluation of hematological parameters and of both relative (%) and absolute (mean pg/cell) quantities of the abnormal Hemoglobin (Hb) Hasharon in 53 heterozygous carriers and 7 double heterozygotes for Hb Hasharon and beta-thalassemia from 43 apparently unrelated families living in the province of Rovigo (northern Italy). Biosynthetic studies are also reported. The data strongly suggest the presence of an alpha-thalassemia-2 determinant closely linked to the alpha Hasharon-chain locus. Selective advantage of heterozygotes carrying such alpha-haplotype would explain the relatively high frequency of Hb Hasharon (0.23%) in northeastern Italy, a past-endemic malaria region. The interaction between Hb Hasharon and beta-thalassemia results in preferential decrease of the abnormal Hb level.

An abnormal, fast-moving haemoglobin was observed in 5 healthy subjects of a family from Calabria (southern Italy). In all these carriers the abnormal haemoglobin, which structural studies identified as Hb Norfolk (alpha2 57 (E6) Gly leads to Asp beta2) [4], occurs at a level averaging 33% of the total haemoglobin. Biosynthetic studies showed no evidence for unbalance of the globin chain synthetic ratio. In order to account for the observed percentages of Hb Norfolk, current concepts about the alpha-globin chain genetic system are reviewed, and different genic arrangements which would be in agreement with the experimental findings are discussed.

This report is concerned with the evaluation of hematological parameters and the percentage level of the abnormal hemoglobin (Hb) G San Josè as found in 4 heterozygous carriers from a family of Sicilian origin. Biosynthetic studies and in vitro recombination experiments strongly indicate that abnormal beta chains are synthesized at lower rate than beta A chains and exhibit a minor affinity (relative to beta A chains) for complementary chains in a condition of relative aA chain deficiency. The possibility that the low affinity of beta G chains for a chains may play a decisive role in controlling the level of the abnormal Hb in the peripheral blood of the present non-a-thalassemic abnormal Hb carriers is therefore discussed.