Journal ArticleDOI
Statistical problems in mutagenicity tests.
TLDR
Means of solving the problems with the necessary consequences for planning of the experiment and its evaluation are discussed and practical recommendations are given applying also to other mutagenicity tests.Abstract:
Everyone involved in planning and carrying out biological experiments has to concern himself with statistical methods. Thus, descriptive statistics (e. g. calculation of the mean) help to present results briefly and comprehensively and, in addition, statistical test procedures permit decisions to be made even in an uncertain situation. The choice of the appropriate statistical procedure is, however, associated with considerable problems. These problems are discussed in detail using the dominant lethal test as an example. Means of solving the problems with the necessary consequences for planning of the experiment and its evaluation are discussed and practical recommendations are given applying also to other mutagenicity tests.read more
Citations
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Journal ArticleDOI
Review of the evidence for the presence or absence of thresholds in the induction of genetic effects by genotoxic chemicals
U.H. Ehling,D. Averbeck,P.A. Cerutti,J. Friedman,H. Greim,A.C. Kolbye,Mortimer L. Mendelsohn +6 more
Journal ArticleDOI
Whole-mammal mutagenicity tests: Evaluation of five methods
Liane B. Russell,B.E. Matter +1 more
TL;DR: Of the methods discussed, the spot test appears most suitable, because it provides a relatively rapid in vivo system capable of detecting both gene mutations and chromosomal changes of various kinds in somatic cells, including some that have been suggested to be involved in tumor promotion.
Journal ArticleDOI
Dominant lethal mutations in male mice.
TL;DR: The reproducibility of results and the sensitivity of the induction of dominant lethal mutations in the collaborative studies demonstrate the usefullness of the method for mutagenicity screening, and the feasibility of standardizing test protocol for the dominant lethal assay in mice is discussed.
Journal ArticleDOI
Reevaluation of the induction of specific-locus mutations in spermatogonia of the mouse by acrylamide.
U.H. Ehling,A. Neuhäuser-Klaus +1 more
TL;DR: It is demonstrated that acrylamide induced germ-cell mutation in mammals exclusively in postmeiotic germ- cell stages, and the induction of specific-locus mutations in spermatogonia of mice is demonstrated.
Journal ArticleDOI
Reproductive effects of inhaled methyl chloride in the male Fischer 344 rat: I. Mating performance and dominant lethal assay
James S. Bus,Thomas E. Hamm +1 more
TL;DR: High concentrations of inhaled MeCl do induce dominant lethal mutations in sperm located within the vas deferens and epididymis at the time of exposure, and it is suggested that the increased preimplantation losses are due to cytotoxic rather than genotoxic effects.
References
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Journal ArticleDOI
Dominant lethal mutations in male mice.
TL;DR: The reproducibility of results and the sensitivity of the induction of dominant lethal mutations in the collaborative studies demonstrate the usefullness of the method for mutagenicity screening, and the feasibility of standardizing test protocol for the dominant lethal assay in mice is discussed.
Journal ArticleDOI
Exact probabilities for tied linear rank tests
W. Stucky,E. Merck,J. Vollmar +2 more
TL;DR: In this paper, an algorithm is presented which permits the exact calculation of the probability of error for a Wilcoaxon situation (with ties) according to a procedure described by Krauth (1971).
Journal ArticleDOI
Ein Verfahren zur exakten Auswertung von 2 × c‐Häufigkeitstafeln
W. Stucky,J. Vollmar +1 more
Journal ArticleDOI
Small numbers in mutagenicity tests.
Alfred Grafe,Joachim Vollmar +1 more
TL;DR: Critical points in comparative tests are not only the methodological questions, but also pharmacokinetic problems of the substance being tested which can only be clarified in the species used for the mutagenicity test if this is ignored.