Comet assay under neutral conditions allows detection of DNA double-strand 
breaks (DSBs), which has consequence to genome instability and carcinogenesis. 
The present study aims to validate the neutral Comet assay for genotoxicity 
assessment in Drosophila melanogaster (Oregon R(+)) with three well known DSBs 
inducers i.e. cyclophosphamide (CP), bleomycin (BLM), cisplatin (CPT) and 
subsequently its efficacy in detecting DSBs in the organism exposed to a well 
known environmental chemical, chromium [Cr(VI)]. Third instar larvae of D. 
melanogaster were fed different concentrations of BLM, CPT and CP 
(50.0-200.0μg/ml) or Cr(VI) (5.0-20.0μg/ml) mixed standard Drosophila food for 
48h. Neutral Comet assay was performed in cells of mid gut and brain from 
control and treated larvae. Our results show a dose-dependent increase in the 
migration of DNA in cells of the exposed organisms. A comparison among DNA 
lesions per mole number of the test chemical in the exposed groups showed that 
both BLM and CPT induce more DSBs than CP. Interestingly, Cr(VI) at 20.0μg/ml 
was found to induce significantly increased (p<0.001) DSBs in the exposed 
organism as compared to the control. The study while validating neutral Comet 
assay in D. melanogaster suggests its use for in vivo assessment of 
environmental chemical induced DSBs.