Abstract
Comparison of microbial mutation rates under the Luria–Delbrück protocol is a routine laboratory task. However, execution of this important task has been hampered by the lack of proper statistical methods. Visual inspection or improper use of the t test and the Mann–Whitney test can impair the quality of genetic research. This paper proposes a unified framework for constructing likelihood ratio tests that overcome three important obstacles to the proper comparison of microbial mutation rates. Specifically, algorithms for likelihood ratio tests have been devised that allow for partial plating, differential growth rates and unequal terminal cell population sizes. The new algorithms were assessed by computer simulations. In addition, a strategy for multiple comparison was illustrated by reanalyzing the experimental data from a study of bacterial resistance against tuberculosis antibiotics.
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Acknowledgments
My special appreciation goes to J. Werngren who explained to me minute experimental details with extraordinary patience. I also own a debt to two conscientious reviewers whose detailed comments substantially improved the presentation of the material in this manuscript. Part of the reported investigation relied heavily on an IBM iDataPlex cluster and an IBM NeXtScale cluster, managed by Texas A&M University Supercomputing Facility.
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Zheng, Q. Comparing mutation rates under the Luria–Delbrück protocol. Genetica 144, 351–359 (2016). https://doi.org/10.1007/s10709-016-9904-3
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DOI: https://doi.org/10.1007/s10709-016-9904-3