Induction of DNA Damage and GADD45B gene Mutation in Zebra fish (Danio rerio) due to Environmentally Relevant Concentrations of Organochlorine Pesticides & Heavy Metals

Zebra fish were exposed to environmentally relevant concentration of pesticides and metals for a period of 14 days. The individual and the combined toxicity of pesticides and metals were studied. Damage caused to the DNA and induction of mutation in the GADD45B gene was investigated in this study. The present investigation revealed that exposure of zebra fish to pesticides and metals induced DNA damage and also mutation in the GADD45B gene. The pesticides treated group (III) showed significantly higher damage followed by metals treated group (II). The DNA damage was comparatively less in the pesticides and metals exposed group (IV). GADD45B gene which is considered to be one of the most important gene involved in G phase arrest, has been found to be mutated in zebra fish when exposed to metals and pesticides. The comparison of amplified gene sequence of GADD45B gene with the sequence of the zebra fish retrieved from the NCBI confirmed the mutation in the gene sequence of zebra fish treated with pesticides and metals. The induction of DNA damage in fish due to contaminants may lead to mutations, which contribute towards the multistage carcinogenesis process.