Vapors of benzene, a parquet varnish and a synthetic thinner induce chromosome loss in cells of the Drosophila wing primordia

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Abstract in foreign language

The consequences ofenvironmental pollution and occupational hazardscalled much attention all over the world, from especially the 1970-es. Agents that cause adverse effects through changing the meaning of the genetic information and/or itsamount inthe cells are of special importance due to their usual delayed action in timeand the induction of cancer. Of the so-called genetic hazards those are of special interests that bring about aneuploidy, one of the preconditionsofcancer formation. No wonder why test procedures have been elaborated to identifyand characterize environmental and genetic agentsthat can generate aneuploidy through the induction of gain and/or loss of chromosomes in the course of cell proliferation. One of the test procedures, the so-called CLADS technique (Chromosome Loss Assay intheDrosophila Soma) was published recently. It is based on the in vivoloss of mwh+Y, a genetically engineered Y chromosome in cells of the developing wing primordia in Drosophila. The mwh+transgene in the mwh+Ychromosome prevents the manifestation of the mutant phenotype of mwh (multiple wing hairs),an excellent recessive cell marker mutation. Following the loss of the mwh+Ychromosome in any cell of the wing primordia, the mwhmutant phenotype becomesexpressed, naturally only in mwhhomozygous genetic background. Descendants of the by now genetically marked cell remain together during the subsequent rounds of mitoses and form anmwhclone (or mosaic spot)in midst of the normal cells (with only one hair per cell)in the wing blade. Significant elevation in the mwh clone frequency -as compared to the control -shows the ability of the analyzed agent to induce chromosome loss. The intensityof chromosome loss can be determined based on the frequency and size of the mwh clones. Duringmy Ph.D. work I analyzed the chromosome loss-inducing ability of benzene, a reference chemical, a common environmental pollutant that has been known to induce chromosome loss. In fact its ability to induce leukemia appears to be related toits aneugenic capacity. In addition to benzene, I studied the effects of vapors of a commonly used parquet varnish and a synthetic thinner. While making use of the novel CLADS technique I confirmedthe chromosome loss-inducing ability of benzeneand showed that vapors of both the parquet varnish and the thinner bring about chromosome loss, albeitless efficientlyas benzene. It is also my conclusion that the CLADS technique is an appropriate tool for high-throughput analysisof environmental and/or genetic agents toanalyze theirabilities to induce chromosomeloss. The technique is sensitive, simple, very inexpensive and quite fast.

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