Haemoglobin Lepore trait: haematological and structural studies on the Italian population.

Haematological data on 59 heterozygotes for haemoglobin (Hb) Lepore and 10 double heterozygotes for Hb Lepore and beta thalassaemia from 36 Italian families are reported. The red cell indices are defined and compared with those of groups of non-thalassaemic and beta thalassaemic subjects of comparable number, age and sex distribution. The relative level of each haemoglobin fraction and the absolute production of single polypeptide chains are calculated in order to compare the expression of the non-alpha chain genes in Hb Lepore trait and beta thalassaemia. Structural studies demonstrate that the haemoglobin Lepore is of the Boston type (delta 87 beta 116) in all subjects, confirming that this type of fusion variant is probably the only one which occurs in Mediterranean populations. The distribution and incidence of the Lepore haemoglobinopathy are discussed.