Bruno Graziani

Genetic Patterns in Thalassemia Intermedia (Constitutional Microcytic Anemia)

Globin chain synthesis has been studied in 17 patients with thalassemia intermedia, and their relatives, also investigated by routine hematologic and hemoglobinic tests. The mean a/non a ratio was always around 2.20-2.30. In patients with severe thalassemia major, used as a control, the mean a/non a ratio was significantly higher, that is 3.11-3.07. Therefore, the hypothesis that the cause of the lesser severity of the thalassemia intermedia is a lesser imbalance of globin chain synthesis, is suggested. One or both the parents of patients with thalassemia intermedia have mild beta-thalassemia and normal alpha/beta ratio, whereas the parents of patients with severe thalassemia major show a marked beta-thalassemia and a mean alpha/beta ration of 1.76. These data suggest that genes for beta +-thalassemia are responsible for thalassemia intermedia, and genes for beta o-thalassemia are responsible for thalassemia major. In two patients with thalassemia intermedia, the association of an alpha-thalassemia gene with homozygous beta-thalassemia that it is well known to reduce the globin chain imbalance typical of the beta-thalassemia, has also been observed.

Heterozygous β-Thalassaemia with Normal Haemoglobin Pattern

Thalassaemia with normal levels of Hb A, and Hb F and with an α/β ratio higher than 1 is described in 4 families. 3 of these families show direct or indirect signs of the presence of the δ-thalassaemia gene along with the β-thalassaemia gene. The fourth family leaves the question as to whether there is a single mutation of the δβ tract or a β + δ-thalassaemia in coupling unanswered. The necessity of knowing of the existence of this thalassaemia which conceals the presence of a β-thalassaemia gene, is stressed, above all in view of the danger that mating between a carrier of this thalassaemia and a carrier of classical β-thalassaemia could result in the birth of children with Cooley’s disease.

Double Heterozygosity for α- and β-Microcytemias

Twelve families with sure or probable heterozygotes for α- and β-microcytemias are described. A constant finding in all these subjects is a high percentage of Hb A2 accompanied by a normal

The Haemoglobin Picture in Cooley's Disease

Summary The haemoglobin picture has been studied in 38 patients with Cooleys anaemia, all homozygous for β‐microcythaemia. In 10 of the patients Hb A1 was completely absent, in the remaindcr it was present on agar gel electrophoresis in amounts varying from minute traces to a rather abundant quota.