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The form of alpha-thalassaemia of the Po river delta presents haematological and globin biosynthetic characteristics similar to alpha-thalassaemia-1 but never gives rise to HB H disease nor to hydrops foetalis. In alpha-thalassaemic subjects originally from this region globin mRNA translation and alpha-globin gene arrangement have been investigated. The data obtained indicate that alpha-globin synthesis and reticulocyte alpha-globin mRNA are reduced by one fourth; in addition, since the defect in alpha-globin synthesis does not change with cell ageing, a possible instability of alpha-globin mRNA is excluded. Restriction enzyme analysis of the DNA shows a normal alpha-globin gene organization. This form of alpha-thalassaemia is therefore of the non-deletion type; its molecular lesion is either at the level of alpha-globin mRNA transcription or processing. The fact that this, as well as other forms of non-deletion alpha-thalassaemia, have a phenotypic expression similar to alpha-thalassaemia 1 is discussed.

Six beta(+)-thalassaemic patients from the Po river delta region have been studied. Using synthetic oligonucleotides as specific hybridisation probes, the beta(+) IVS I mutation (G----A at position 108) was demonstrated. This lesion and the enzyme polymorphism pattern in the subjects examined are the same as have been described for other Mediterranean beta(+)-thalassaemias. Antenatal diagnosis through DNA analysis of beta(+)-thalassaemia is therefore possible. The production of beta globin in a beta(+), homozygote and in a beta (+), beta(0) 39 (nonsense mutation at codon 39) double heterozygote is approximately 20% and 10% respectively of total non-alpha globin synthesis. Despite some overlapping of the results, similar beta globin synthesis levels have been obtained in 43 beta(+)-thalassaemia patients. This suggests that in the Po river delta region the most common thalassaemic genes are beta(0) 39 and beta(+) IVS I.

A library of genomic DNA was prepared from a patient with beta o Ferrara thalassaemia: random human DNA fragments (15 - 20 Kb) have been joined to phage lambda vectors and cloned has viable phage particles (4). 4x10(5) phages have been screened for their content in beta globin gene sequences, using a human beta cDNA plasmid (5) as hybridization probe. Five positive clones have been isolated and characterized by restriction endonuclease cleavage analysis and by the hybridization experiments. The results obtained allow the precise localization of the human fragments inside the beta like globin gene cluster (6). The comparison of the thalassaemic fragments with the normal DNA (6 - 7) shows two different restriction endonuclease sites, for Xba I and Eco RI respectively, downstream from the human beta globin gene.

In subjects carrying the haemoglobin Hasharon mutation (alpha 47 replaced by His), originally from the delta of the Po river (Northern Italy), the concentration of the alpha-globin variant has been evaluated and found to be approximately 32%, a value definitely higher than that reported for the same mutant haemoglobin in other regions. Restriction enzyme analysis has been carried out on the DNA from these subjects; the data obtained indicate the presence of three alpha-globin genes per diploid cell. Family studies further show that the two normal genes are located on one chromosome and the Hasharon gene on the other. The origin of the single alpha-gene in the Hasharon-carrying subjects of the Ferrara region is discussed in connection with their haematological and biosynthetic data.

Demethylation of specific sites or restricted genomic regions has been reported to correlate with gene activation and also with carcinogenesis. As abnormal expression of Estrogen Receptor (ER) could be involved in the genesis or progression of tumors in estrogen target tissues, the methylation of ER gene has been compared in 8 endometrial carcinomas and 29 normal endometria. In order to look for a correlation between methylation and expression, levels of ER RNA were also measured. While the 5' region of ER gene was found to be demethylated in both normal and carcinomatous tissues, there was demethylation of some specific sites in the internal part of the gene only in the carcinomas examined. In addition, in the carcinomatous tissues the levels of ER RNA were low, indicating that an increase of ER gene hypomethylation does not raise, and even may reduce, the ER expression in endometrium. The abnormal undermethylation observed in ER gene appears to be unrelated to general DNA hypomethylation which is frequently present in neoplastic tissues; nor has it been found in ER DNA isolated from breast carcinomas. These data strongly support the hypothesis that such a methylation is specifically related to endometrial transformation and therefore it can be considered an additional marker of this disease.

A diagnosis of pro-B acute lymphoblastic leukemia (ALL) with CD15+ was made in a 42-year-old woman, 12 months after the treatment of uterine adenocarcinoma by carboplatinum, anthracyclines, etoposide and radiotherapy. Molecular cytogenetic studies revealed a karyotype with multiple chromosome changes, including the t(4;11)(q21;q23) and a 17p-chromosome, with MLL disruption and 17p13/p53 gene deletion in 86% of the cells. A p53 exon 6 mutation was documented, resulting in p53 protein stabilization, with 20% of the cells reacting with the 1801 anti-p53 monoclonal antibody. Dual-color FISH using MLL and p53 probes was performed on peripheral blood smears, providing direct evidence of the involvement of the blast cells and of the granulocytic lineage. Only a partial, shortlasting response was obtained by induction treatment, confirming that a poor prognosis is associated with therapy-related ALL with the 4;11 translocation. [ABSTRACT FROM AUTHOR]