The comet moment ratio and other parameters obtained by applying image processing techniques and feature extraction to the SCGE assay

In single-cell gel electrophoresis (SCGE), or the `comet´ assay, there is a need for classification of the large number of comet-shaped images that are formed. In this paper, we discuss new parameters that we have developed to measure the extent of DNA damage and which may be useful in the classification process. A variety of human and mouse cells treated with different agents were tested. Two new parameters are proposed. (1) The main new parameter has been termed the “comet moment ratio”. We have defined this parameter as being the ratio of the largest to the smallest second-order central moments. (2) The `tail shape ratio´ is the ratio of the tail width to the head diameter. Neither of the parameters is dependent upon comet size. Results show that the new parameters relate closely to comet shape