Sister chromatid exchange

{
  "id": "MLC-T-ENV-025673",
  "term": "Sister chromatid exchange",
  "field": "Environment",
  "term_source": "Sister Chromatid Exchange",
  "definition": "Reciprocal interchange of the two chromatid arms within a single chromosome. This exchange is visualized during the metaphase portion of the cell cycle and presumably requires the enzymatic incision, translocation and ligation of at least two DNA helices.(c) Test method - (1) Principle of the test method. (i) Groups of rodents are exposed by the inhalation route for a minimum of 6 hours/day over a period of not less than 28 days to three or more concentrations of a test substance in air. Groups of animals are sacrificed at the end of the exposure period and blood lymphocyte cell cultures are prepared from study animals. Cell growth is suspended after a time and cells are harvested, fixed and stained before scoring for SCEs. Researchers may need to run a trial at the highest tolerated concentration of the test atmosphere to optimize the sample collection time for second division metaphase cells.",
  "subject": "Biological substances",
  "references": [
    "40 CFR 79.65 (CFR 2013)"
  ],
  "url": "https://mlchart.com/terminology/environment/sister-chromatid-exchange/"
}