Implementation of the fluorescent in situ hybridization technique at the Northeast Regional Center for Nuclear Sciences, PE, Brazil

Biological dosimetry arose from the need to quantify the dose absorbed by the human body after incidents or accidents involving ionizing radiation. This type of dosimetry is used in situations where the absorbed dose to the whole body is unknown or uncertain, such as in cases of accidental or occupational exposure. Among the techniques developed for this purpose are conventional cytogenetic analysis of dicentric chromosomes and the micronucleus technique by blocking cytokinesis. However, these techniques are applied to estimate recent damage to ionizing radiation, as they are representative of unstable damage and their frequencies are reduced with the elimination of lymphocytes through the rate of cell renewal [1]. For this reason, cytogenetic markers such as translocations are used to recognize and study the most persistent damage to cells. Reciprocal translocations have been used for exposures that occurred years to decades in the past. Some case studies in retrospective dosimetry confirm the use of FISH - Fluorescent in situ Hybridization - as the most reliable test for retrospective biodosimetry. As there is still no retrospective dosimetry service in Brazil, this work aimed to implement the FISH technique in the Biological Dosimetry Laboratory of the Northeast Regional Nuclear Science Center - CRCN-NE/CNEN, as the first step towards establishing a dose-response calibration curve for this biodosimetric technique. (author)