mikronukleiustesti

The micronucleus test, or mikronukleiustesti in German, is a widely used genotoxicity assay to detect chromosomal damage. It is employed in various fields, including toxicology, environmental monitoring, and human biomonitoring. The test is based on the observation of micronuclei, which are small, extra-nuclear bodies containing fragments of chromosomes or whole chromosomes that were not properly segregated during cell division.

The principle of the micronucleus test involves exposing cells to a test substance, either in vitro or in vivo. Following exposure, the cells are allowed to divide. During cell division, if there is breakage of chromosomes or mis-segregation of chromosomes, these fragments or whole chromosomes will fail to be incorporated into the main nuclei and will instead form micronuclei. These micronuclei can then be visualized and quantified using microscopy, often after staining the cells.

Different cell types can be used for the micronucleus test, including mammalian cells in culture, human lymphocytes, and cells from various tissues in experimental animals. For in vivo studies, peripheral blood lymphocytes or bone marrow cells are commonly analyzed. The presence and frequency of micronuclei serve as an indicator of the genotoxic potential of the substance being tested. A significant increase in micronuclei formation compared to control groups suggests that the test substance is clastogenic (causing chromosome breaks) or aneugenic (causing chromosome mis-segregation). The micronucleus test is a valuable tool for assessing the risk of mutagens and carcinogens.