RESUMO
BACKGROUND: The t(14;18) translocation, present in 90% of follicular non-Hodgkin's lymphomas (NHL), has been found to exist in low levels in healthy persons. Its clinical/prognostic significance in healthy populations is unknown, and risk factors for its development have not been determined. Our objectives were to assess the prevalence of t(14;18) in individuals without NHL, comparing residents of agricultural settlements (kibbutzim) with city dwellers, as well as first degree relatives of NHL cases. PATIENTS AND METHODS: Residents of kibbutzim and members of two control groups: 1) Jerusalem residents--randomly selected hospital administrative workers and 2) first degree family members of lymphoma patients were interviewed extensively regarding exposures and had blood drawn for t(14;18) determination. The translocation was detected after B-cell purification of blood samples with CD-19 microbeads (Mini-Macs) using nested PCR. The method detects the translocation in a BCL2 positive cell line after dilutions of up to 1:10(5) with normal peripheral blood lymphocytes. RESULTS: Nineteen of two hundred thirty healthy individuals (8.3%) tested were found to be positive for t(14;18). No statistically significant differences in the prevalence of t(14;18) were detected among the rural and urban populations. Five of thirty-four (11.9%) family members tested positive for t(14;18). No age or sex differences between t(14;18) positive and negative individuals were found. No significant association with exposure to specific agricultural or other chemicals was found. CONCLUSIONS: The presence of the t(14;18) translocation in healthy individuals was not associated with agricultural residence in this preliminary study. Whether relatives of patients with NHL are at increased risk will require further study in larger populations. Specific exposures affecting the onset of this translocation have not been ruled out. The significance of this translocation in healthy individuals remains unknown.
Assuntos
Doenças dos Trabalhadores Agrícolas/genética , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Linfoma não Hodgkin/genética , Exposição Ocupacional/efeitos adversos , Translocação Genética , Doenças dos Trabalhadores Agrícolas/diagnóstico , Doenças dos Trabalhadores Agrícolas/epidemiologia , Sequência de Bases , Distribuição de Qui-Quadrado , Feminino , Humanos , Israel/epidemiologia , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/epidemiologia , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Prevalência , Probabilidade , Valores de Referência , Medição de Risco , População Rural , População UrbanaRESUMO
Thirteen chronic myeloid leukemia (CML) patients, 10 with variant Philadelphia (Ph) translocations and 3 Ph negative cases, were analyzed by fluorescence in situ hybridization (FISH) with the use of BCR and ABL cosmid probes and a chromosome 22 painting probe. In the variant Ph translocations, the BCR-ABL fusion gene was located on the Ph chromosome; in 1 CML Ph-negative patient, the BCR-ABL fusion gene was located on the Ph chromosome; and, in 2 patients, it was located on chromosome 9. The chromosome 22 painting probe was detected on the third-party chromosome of the variant translocation, and in none of the variant translocations was there any detectable signal on chromosome 9. In CML patients with clonal evolution of a simple Ph, a signal of the chromosome 22 painting probe was detected on the der(9) of the Ph translocation. It was concluded that the variant Ph translocations evolved simultaneously in a three-way rearrangement. The clinical parameters of the 13 patients were similar to those of a large group of CML patients with a simple Ph translocation. It is suggested that, to determine the prognosis of CML patients with a complex karyotype, FISH analysis with a chromosome 22 painting probe be performed.
