No abstract

We have identified a rare BCR-ABL chimaeric gene with multiplex and nested RT-PCR in a patient with an unusually aggressive chronic myeloid leukaemia. cDNA sequencing showed an in-frame rearrangement with a breakpoint in BCR exon e13 (b2) and fusion with ABL exon 3 following skipping of the entire ABL exon a2. These data confirm the heterogeneity of breakpoints in BCR-ABL rearrangements.

Background: Genetic predisposition may play a role in the prevalence of gastric cancer (GC). Aim: To investigate the relationship between selected interleukin-1 (IL-1) loci polymorphisms and gastric cancer risk in the Central-Western region of Venezuela, where gastric cancer represents the first cause of cancer-related deaths. Material and methods: In a case-control study, we compared the frequencies of IL-1B-511 and IL-1B+3954 biallelic polymorphism, and the pentallelic VNTR of IL-IRN in 84 gastric adenocarcinoma paraffin-embedded biopsies and 84 endoscopic biopsies from cancer-free controls. Results: No significant increase in genotypic frequencies in gastric cancer was observed for any of the IL-1B-511 allelic combinations. However, in a logistic regression analysis, a significant association emerged for the IL-1B+3954C carrier genotype (odds ratio (OR): 6.2; 95% confidence intervals (CI) 1.3-28.8). On the other hand, a significantly higher risk was evidenced for the IL-IRN*2/*2 genotype (OR: 7.0; 95% CI 2.3-21.5). Only patients with a well/moderately-differentiated adenocarcinoma that were homozygotes for the IL-IRN*2/*2 genotype, had a higher risk than the complete gastric cancer group (OR: 8.1, 95% CI 2.5-26.8). Some genotype combinations among IL-1B-511, IL-1B+3954 and IL-IRN showed an increased risk for developing gastric cancer and well/moderate differentiated adenocarcinoma, that was dependent of the presence of IL-IRN*2/*2 genotype. Conclusions: IL-IRN*2/*2 genotype is associated with increased risk of gastric cancer in the Venezuelan population (Rev Méd Chile 2009; 137: 63-70).

No abstract

Heterozygous carriers of HPRT1 mutations responsible for Lesch-Nyhan syndrome can be detected by analysis of somatic cell hybrids derived from peripheral blood lymphocytes and Hprt1-negative cells of rodent origin followed by selection in culture medium containing hypoxanthine, aminopterine, and thymidine (HAT). The parental origin of the X chromosome containing the normal HPRT1 allele in HPRT1(+) hybrid cell lines can be determined by molecular haplotyping attributable to highly polymorphic X-linked markers. We used this procedure to study a presumed carrier whose paternal active X chromosome always segregated in the cell hybrids derived from her. Conversely, her maternal X chromosome was systematically absent in most cell hybrids, or when present, it was inactive and coexisted with an active, paternal X chromosome. These results clearly demonstrated that the proband was a heterozygous carrier of a mutation responsible for HPRT1 deficiency.