title: Evaluation of impairment of DNA in marine gastropod, Morula granulata as a biomarker of marine pollution.
abstract: 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.
authors.affiliation: Chemical Oceanography Oceanography Division, CSIR - National Institute of Oceanography Dona Paula, Goa 403004, India; Global Enviro-Care, Kevnem, Caranzalem, Goa 403002, India. Electronic address: asarkar52@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: Sarkar
authors.affiliation: Chemical Oceanography Oceanography Division, CSIR - National Institute of Oceanography Dona Paula, Goa 403004, India.
authors.forename: Jacky
authors.initials: J
authors.lastname: Bhagat
authors.affiliation: Clinical Division of Fish Medicine, University of Veterinary Medicine, Veterinarplatz 1, 1210 Vienna, Austria.
authors.forename: Subhodeep
authors.initials: S
authors.lastname: Sarker
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis*; D020552:Comet Assay; D004247:DNA / Q000187:drug effects*; D004249:DNA Damage; D004784:Environmental Monitoring / Q000379:methods*; D007194:India; D009028:Morula / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D014874:Water Pollutants, Chemical; D004247:DNA
keywords: Alkaline unwinding assay; Biomarker; Comet assay; DNA impairment; Genotoxic contaminants; Morula granulate