Evaluation of impairment of DNA in marine gastropod, Morula granulata as a biomarker of marine pollution

• Published in: Ecotoxicology and environmental safety Vol. 106; pp. 253 - 261
• Main Authors: Sarkar, A., Bhagat, Jacky, Sarker, Subhodeep
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01-08-2014; Elsevier
• Subjects: Alkaline unwinding assay; Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Biomarker; Biomarkers - analysis; Coastal environments; Comet Assay; Contaminants; Contamination; Deoxyribonucleic acid; DNA - drug effects; DNA Damage; DNA impairment; Ecotoxicology, biological effects of pollution; Environmental Monitoring - methods; Fundamental and applied biological sciences. Psychology; Gastropoda; Genotoxic contaminants; Granulation; India; Integrity; Marine; Marine and brackish environment; Morula - drug effects; Morula granulata; Morula granulate; Olea; Sampling; Water Pollutants, Chemical - toxicity; Arabian Sea; Indian Ocean; Asia; India; ISW, India, Goa; India, Goa, North Goa Dist., Dona Paula; ISW, India, Goa, Anjuna; Genotoxic contaminants; Alkaline unwinding assay; Biomarker; DNA impairment; Morula granulate; Comet assay; Toxicity; Mutagenicity testing; Genotoxicity; Unwinding; Biological marker; Gastropoda; Conformational changes; Marine environment; DNA; Water pollution; Invertebrata; Mollusca; Genotoxity test
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2014.04.023

The impairment of DNA in marine gastropod Morula granulata was evaluated in terms of the loss of DNA integrity in the species as a measure of the impact of genotoxic contaminants prevalent in the marine environment along the coast of Goa, India. The extent of DNA damage occurred in the marine gastropods collected from different sampling sites such as Arambol, Anjuna, Sinquerim, Dona Paula, Bogmalo, Hollant, Velsao, Betul and Palolem along the coast of Goa was measured following the technique of partial alkaline unwinding as well as comet assays. The highest DNA integrity was observed at Arambol (F, 0.75), identified as the reference site, whereas the lowest DNA integrity at Hollant (F, 0.33) situated between the two most contaminated sites at Bogmalo and Velsao. The impact of genotoxic contaminants on marine gastropods was pronounced by their low DNA integrity at Sinquerim (F, 0.40) followed by Betul (F, 0.47), Velsao (F, 0.51), Anjuna (F, 0.54), Bogmalo (F, 0.55), Dona Paula (F, 0.67) and Palolem (F, 0.70). The extent of DNA damage occurred in M. granulata due to ecotoxicological impact of the prevailing marine pollutants along the coast of Goa was further substantiated by comet assay and expressed in terms of %head-DNA, %tail DNA, tail length and Olive tail moment. The single cell gel electrophoresis of M. granulata clearly showed relatively higher olive tail moment in the marine gastropod from the contaminated sites, Anjuna, Hollant, Velsao and Betul. The variation in the mean %head DNA at different sampling sites clearly indicated that the extent of DNA damage in marine gastropod increases with the increase in the levels of contamination at different sampling sites along the coast. The stepwise multiple regression analysis of the water quality parameters showed significant correlation between the variation in DNA integrity and PAH in combination with NO3, salinity and PO4 (R¯2, 0.90). The measurement of DNA integrity in M. granulata thus provides an early warning signal of contamination of the coastal ecosystem of Goa by genotoxic contaminants.
•Impairment of DNA in Morula granulata acts as a biomarker of marine pollution.•Loss of DNA integrity in Morula granulata provides an early warning of genotoxicity.•DNA damage in Morula granulata was measured by alkaline unwinding and comet assays.•Significant correlation found with DNA integrity and PAH, NO3, salinity and PO4.•Morula granulata can be used as a sentinel species for molecular biomarker studies.