title: The distribution of the tail moments in single cell gel electrophoresis (comet assay) obeys a chi-square (chi2) not a gaussian distribution.
abstract: The parameter tail moment in single cell gel electrophoresis (comet assay) is calculated as the product of the two values: the percentage of DNA in the comet tail and the tail length in microm. Experiments were performed with cultured mammalian cells: B-Lymphoblasts, epithelial cells of a kidney tissue and a plate-epithelial cell line of a human carcinoma. They were irradiated in suspension with UV A at lambda = 343 nm, generated by an excimer laser-pumped dye laser. DNA migration was assessed and analysed. It is demonstrated that the distribution of the tail moments can be fitted by a chi2 (chi-square) distribution, whereas the factors of the product tail moment tend to be normally distributed. From this result, consequences for the statistical evaluation of the results can arise, especially for the computation of the confidence limits and for the valuation of the parameter tail moment from other comet assay experiments.
authors.affiliation: Institute of Molecular Biotechnology, Jena, Germany. ebauer@imb-jena.de
authors.forename: E
authors.initials: E
authors.lastname: Bauer
authors.forename: R D
authors.initials: RD
authors.lastname: Recknagel
authors.forename: U
authors.initials: U
authors.lastname: Fiedler
authors.forename: L
authors.initials: L
authors.lastname: Wollweber
authors.forename: C
authors.initials: C
authors.lastname: Bock
authors.forename: K O
authors.initials: KO
authors.lastname: Greulich
mesh_terms: D002478:Cells, Cultured; D016009:Chi-Square Distribution; D004586:Electrophoresis / Q000379:methods*; D006801:Humans; D014407:Tumor Cells, Cultured; D014466:Ultraviolet Rays