Comet assay, for DNA damage

Collins, A. R. (2004). The COMET assay for DNA damage and repair. Molecular... 

Lower worker exposures were still associated with positive findings in the Comet assay for DNA damage. ItaUan battery plant workers, mean PbB 39.6 pg/dl, showed statistically significant increases in tail moment versus controls (mean 4.4 tig/dl). Indian secondary smelter workers (Devi et al., 2003), with mean PbB 24.8 pg/dl, showed correlations of Comet assay results with both PbB and duration of Pb exposure. Taiwanese battery plant employees (Wu et al., 2002), with mean PbB value of 32.5 pg/dl in the higher Pb exposure group, showed a significant relationship of PbB with the percent of DNA—protein cross-links. 

Collins AR (2004) The comet assay for DNA damage and repair principles, applications, and limitations. Mol Biotecbnol 26(3) 249-261 ECVAM (2012) http //ecvam.jrc.it/consulted. January 2012... 

In Vivo (or In Vitro) Single-Cell Gel Electrophoresis Test for DNA Damage (Comet Assay)... 

Figures. Comet assay is shown for human K562 cells exposed to an extract produced from particulate matter released from sample PM 5 filters, to an extract derived from an unloaded filter, or to hydrogen peroxide (100 pM) as a control. Cells with little or no DNA damage are labeled 1 and 2, and those with extensive damage are labeled 3 and 4.

Sauvaigo S, Petec-Calin C, Caillat S, Odin F, Cadet J (2002) Comet assay couple to repair enzymes for the detection of oxidative damage to DNA induced by low doses of y-radiation use of YOYO-1, low-background slides, and optimized electrophoresis conditions. Anal Biochem 303 107-109 Schnabel W (1986) Pulse radiolysis studies concerning oxidative degradation processes in linear polymers. Radiat Phys Chem 28 303-313... 

DNA repair can be detected by the same assays (alkaline elution and Comet) that are used to detect DNA damage, but with various time intervals between the end of exposure and the time of sampling. An additional assay for assessing DNA repair has been utilized for many years, namely the unscheduled DNA synthesis (UDS) assay. The endpoint measured is the uptake of tritiated thymidine into DNA repair sites following exposure. The sensitivity of the assay is relatively low, especially in vivo, and this limits its predictive value for hazard identification. Thus, a negative response in a UDS assay has very limited value because of this low sensitivity. 

As for the soil compartment, the comet assay on coelomocytes of earthworms (Eisenia foetida) kept in PAH-contaminated soil samples had higher DNA damage than in control samples (Verschaeve, 2002). However no dose-effect relationship was observed. Also, the levels of PAH-DNA adducts in Lumbricus terrestris, another earthworm species, kept on industrially contaminated soils increased with exposure time (Van Schooten et al., 1995). Few surveys have been performed on terrestrial plant species, but trifluralin was shown to induce a significant increase in tail length in the comet assay applied on the leaves of Viciafaba (Bierkens et al., 1998). 

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