Measuring Mutation Rates Using the Luria-Delbrück Fluctuation Assay

  • Gregory I. LangEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1672)


The Luria-Delbrück fluctuation assay is one of the most commonly used methods for measuring the mutation rate in microorganisms. Specifically, it is used to measure the mutation rate at a particular locus or loci at which mutations give rise to a selectable phenotype. Here, I outline the essential features of performing Luria-Delbrück fluctuation assays as well as common missteps and tips for improving the accuracy of mutation rate estimates. In addition, I provide tools for analyzing data from fluctuation assays. This 96-well plate protocol has been optimized for use in yeast but should perform equally well for a range of microorganisms using standard microbiological methods.

Key words

Mutation rate Fluctuation test Poisson distribution 



I thank Sean Buskirk, Katie Fisher, and Dan Marad for comments on this manuscript. This work was supported by a New Investigator grant from the Charles E. Kaufman Foundation of The Pittsburgh Foundation.

Supplementary material

393503_1_En_3_MOESM1_ESM.docx (64 kb)
LangFluctuationAssay-161201(DOCX 64 kb).


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Copyright information

© Springer Science+Business Media LLC 2018

Authors and Affiliations

  1. 1.Department of Biological SciencesLehigh UniversityBethlehemUSA

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