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150 subjects affected with HD and 45 at high risk for the disease were typed for the CAG trinucleotide repeat at the 5' end of IT15. In all of them we find expanded segments showing marked instability upon transmission. Their length distribution matches those previously reported and inversely correlates (-0.686) with age at onset. Two at risk sibs from a large HD pedigree show expanded segments that overlap the normal distribution and can represent reductions from the HD to the normal range. A case of instability on a normal chromosome is also reported. Finally, an analysis of the CAG repeat as a function of three polymorphic DNA markers at D4S127 and D4S95 loci shows no significant difference in the average repeat length on HD chromosomes grouped according to the cosegregating allele of each marker or to the corresponding haplotype. Despite the marked heterogeneity in repeat length among HD families, haplotypes are not associated with different values around which the repeat length fluctuates.

Background and Methods: Immunoglobulin (Ig) gene expression and rearrangements provide information about cell lineage, clonality and differentiation of neoplastic lymphoid cells. We performed flow cytometry and Southern blot analysis in 25 patients with chronic lymphocytic leukemia (CLL) from the Po River delta region (Northern Italy), in order to correlate surface immunological phenotype and heavy and light chain gene rearrangements with clinical stages., Results: In these 25 CLL cases, as in the larger group of 165, k-positive (k+) patients were more frequent than lambda-positive (lambda +) ones by a ratio of 59:41, with a predominance of lambda + in stage II (46:54) and of K+ in stage IV (77:23). However, the survival behavior of lambda + and k+ patients was not statistically different. Ig gene rearrangements were found in all patients in accordance with the immunophenotype. When Ig gene analysis was performed on two different occasions in 7 of the 8 who received chemotherapy, there was an increase in the percentage of the germline band. This variation was inversely related to changes in WBC count. In the treated subject who showed a reduction of both WBC count and the germline, there was rapid disease progression and short survival., Conclusions: Analysis of Ig gene rearrangements in our CLL patients demonstrated: i) the monoclonality of neoplastic cells; ii) no correlation between rearrangements and clinical stages, and iii) that this analysis may be a useful tool in evaluating biological behavior in selected CLL cases showing a discrepancy between hematological data and clinical response to therapy.

Ig gene analysis, carried out in 25 patients failed to show rearrangement patterns typical of each stage, but, nevertheless, confirmed the monoclonal origin of leukemic cells in these patients. In addition, in 14 of them the pattern of Ig gene rearrangements measured on two different occasions was analyzed. Only in patients who had received chemotherapy, the intensity of the Ig germline band was greater than that of the rearranged bands, indicating the reduction of lymphocytosis after the therapy. Thus, though Ig gene rearrangement could not distinguish the CLL stage, our data confirm the usefulness, at all clinical stages, of Ig gene analysis as a tool in the evaluation of the efficiency of the therapy.

A c-myc DNA with a deletion which includes 5' flanking, exon 1 and intron I sequences has been found in normal white blood cells of a mother and one daughter in a Northern Italian family. In addition, the degree of methylation of specific CCGG sites in the truncated DNA is lower in both mother and daughter than that found in normal DNA. It is of interest that deletions of the first exon and hypomethylation of the c-myc gene have usually been observed only in some neoplasias. However, our results demonstrate that the c-myc truncated DNA with the abnormal methylation pattern here reported is a genomic variant which by itself is not related to neoplastic transformation.

By analyzing c-myc specific fragments from white blood cell DNAs of 98 gastric cancer patients and 46 control subjects, we observed 6 unexpected patterns due to presence of a variant c-myc gene in addition to the normal gene. Restriction enzyme mapping indicated that the variant c-myc gene was the result of a 5' deletion including the first exon and part of the first intron. The deleted region, non-coding for the functional c-myc protein, contains sequences involved in the regulation of transcription. We therefore analyzed the c-myc mRNAs from a subject carrying the truncated gene and from a subject homozygous for the normal gene in Northern blotting experiments: the mRNAs were indistinguishable, both qualitatively and quantitatively. Family analysis demonstrated that the truncated gene is inherited in a Mendelian fashion. Population studies showed that the allele, both in patients and in control subjects, reaches a polymorphic frequency (2.1% for the whole sample) and that it is not associated with a risk of cancer.

In the context of a multidisciplinary study program whose purpose is to investigate the genetic aspects of Huntington's Chorea (HC), the authors conducted an epidemiological descriptive research extended to the population residing in the province of Ferrara in a time period including the years from 1971 to 1987. On December 31st, 1987 we estimated a prevalence rate of 1.89 cases of HC per 100,000 inhabitants; in the years 1971-1987 the incidence rate was of 0.11 per 100,000/year and the mortality rate of 0.06 per 100,000/year. In the last years considered for the study, the incidence and the prevalence showed a relative increase indicating that HC still exists in the ferrarese population, despite a greater public awareness. With the aim to organize preventive actions and to reach the preclinical diagnosis of the disease we singled out 83 subjects at risk the study area.

DNA from 20 Italian haemophilia B patients was analysed by the Southern blotting technique and hybridisation to a factor IX cDNA probe. A large deletion of factor IX gene was detected in one patient with antibodies to the infused factor; the EcoRI pattern of the other 19 subjects examined was normal.

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.

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.

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.