AN OPTIMIZED COMET ASSAY PROTOCOL FOR DROSOPHILA MELANOGASTER

Genotoxins can cause various disorders in chromosome and DNA structure such as gene mutations, chromosome abnormalities and DNA chain breaks. This situation has been associated with the concept of genetic toxicity. Genotoxicity tests have been developed to predict the possible effects of genotoxins on all living things in nature. The single cell gel electrophoresis assay (SCGE, also known as comet assay) is used as the fastest, easy and sensitive. The Comet method is based on distinctive migration characteristics of DNA molecules having different electrical charges and molecular weights at alkaline pH. According to this method, nucleolus’ and cells can be visualized by staining with a fluorescent dye by first placing between the agarose layers and then running at alkaline electrophoresis buffer and lysis solution and lastly applying neutralization procedure. The displayed DNA fractures are measured and evaluated according to tail length. DNA images are graded according to the degree of damage. DNAs that are not damaged are evaluated as arbitrary units (AU) by scoring 0 and damage DNAs are scored from 1 to 4 according to the degree of damage. Comet assay is a useful method in evaluating the potential toxic effect. Drosophila melanogaster is the most important non-mammalian organism used in the fields of medicine and biology. Drosophila melanogaster has been used for many years as an in vivo model organism for potential toxicity and genotoxicity studies. It is important to determine the damage of genotoxins on DNA. It was preferred because it was easy to obtain and grow in the laboratory, the larvae were cheap and the life cycle was short-lived. Comet analysis using Drosophila melanogaster tissues to determine the damage of various genotoxins on DNA is an effective and easy method. This study aims to explain the alkaline Comet assay aimed to determine the effect of general various genotoxins on Drosophila melanogaster tissues.

Keywords:

Drosophila Melanogaster, Genotoxicity Comet assay,

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