Measurements of genotoxic potential of cadmium in different tissues of fresh water climbing perch Anabas testudineus (Bloch), using the comet assay

The present investigation was undertaken to study the induction of DNA damage by CdCl2 in freshwater climbing perch Anabas testudineus (Bloch) using alkaline single cell gel electrophoresis (comet assay). The DNA damage was measured in the tissue of gill, kidney and liver as the percentage of DNA in comet tails and comet heads in the tissue of the fish specimens exposed to 0.1, 1.0, 2.0 mg L−1 concentrations of CdCl2. It was found that at all the concentrations of CdCl2, the liver tissue exhibited significantly (p < 0.01) higher DNA damage, followed by kidney and gill tissue. The DNA damage was found to be concentration dependent, with the highest DNA damage at 2 mg L−1 concentration, followed by 1.0 and 0.1 mg L−1. At the concentration of 2 mg L−1 of CdCl2, the tail and head DNA of liver tissue were 38.81% and 59.49%, in kidney tissue the values were 32.37% and 64.66% whereas in gill tissue the values were 31.30% and 66.40% respectively. This study conclude that comet assay can be used for in vivo laboratory experiment using fish as model for screening the genotoxic potential of cadmium.