In gamma-beta-thalassaemia, human gamma- and beta-globin gene expression is suppressed; this results in a severe anaemia in newborns which subsequently develops into a beta-thalassaemia syndrome in adult life. This hereditary disease is now shown to be the result of a deletion of at least 40,000 base pairs of the gammadeltabeta-globin gene locus. The gamma- and delta-globin genes are deleted in the affected chromosome but, surprisingly, the beta-globin gene is still present, together with a large segment of the DNA sequences flanking the gene on its 5'-side and the entire region on the 3'-side of the gene. Hence, a deletion of DNA far from the beta-globin gene results in the suppression of its activity.

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The human erythrocyte contains a certain quantity of glutathione (a tripeptide consisting of glutamic acid, glycine and cysteine). The lesser part of the total erythrocyte glutathione is present as oxidized glutathione (GSSG), the main part, however, is kept in the reduced form (GSH), by a reaction catalysed by the enzyme glutathione reductase (GSH Red.) :The GSH has an important function, maintaining the integrity of the erythrocyte [6]. The mechanism of the protection of the erythrocyte by GSH is largely unknown, although there are several speculations concerning its mode of action.The TPNH, (reduced triphosphopyridine nucleotide) necessary for the reduction of glutathione is derived from the first and second step of the pentose-phosphate pathway, a route through which 10-20% of the total glucose in the erythrocyte is metabolised [5]. These reactions are : Glucose-6-phosphate + TPN ~ glucose-6-phosphate dehydrogenase 6-phospho-gluconate dehy drogenase -+ 6-phospho-gluconate + TPNH, 6-phospho-gluconate +TPN -+ ribose-5-phosphate + TPNH,Recently we observed a patient with a chronic, fairly well compensated, non-spherocytic haemolytic anaemia. The absence of GSH in the erythrocytes of this patient could repeatedly be demonstrated. The preliminary observations in this patient and the results of the haematological and biochemical determinations carried out on blood samples of several relatives are briefly reported.

Stimulation of cellular fatty acid uptake by induction of insulin signalling or AMP-kinase (AMPK) activation is due to translocation of the fatty acid-transporter CD36 from intracellular stores to the plasma membrane (PM). For investigating the role of the four Cys-residues within CD36's cytoplasmic tails in CD36 translocation, we constructed CHO-cells expressing CD36 mutants in which all four, two, or one of the intracellular Cys were replaced by Ser. Intracellular and PM localization of all mutants was similar to wild-type CD36 (CD36wt). Hence, the four Cys do not regulate sub-cellular CD36 localization. However, in contrast to CD36wt, insulin or AMPK activation failed to induce translocation of any of the mutants, indicating that all four intracellular Cys residues are essential for CD36 translocation. The mechanism of defective translocation of mutant CD36 is unknown, but appears not due to loss of S-palmitoylation of the cytoplasmic tails or to aberrant oligomerization of the mutants.