Optimizing PCR for Mouse Genotyping: Recommendations for Reliable, Rapid, Cost Effective, Robust and Adaptable to High-Throughput Genotyping Protocol for Any Type of Mutation

Genotyping consists of searching for a DNA sequence variation localized at a well-defined locus in the genome. It is an essential step in animal research because it allows the identification of animals that will be bred to generate and maintain a colony, euthanized to control the available space in the animal facility, or used in experiment protocols. Here we describe polymerase chain reaction (PCR) genotyping protocols for fast, sensitive, easy, and cost-effective characterization of mouse genotype. We discuss optimization of parameters to improve the reliability of each assay and propose recommendations for enhancing reproducibility and reducing the occurrence of inconclusive genotyping. All steps required for efficient genotyping are presented: tissue collection; sample verification and direct DNA lysis; establishment of a robust genotyping strategy with reliable, rapid, and cost-effective assays; and finally, transition to high-throughput automatized PCR, including mix miniaturization and automation. © 2019 The Authors. Basic Protocol 1: Tissue sampling methods and procedure Basic Protocol 2: Sample verification and DNA lysis Basic Protocol 3: Design of a genotyping strategy Basic Protocol 4: Moving to high-throughput genotyping.

Characterization and Validation of Cre-Driver Mouse Lines

Conditional gene manipulations in mice are increasingly popular strategies in biomedical research. These approaches rely on the production of conditional genetically engineered mutant mouse (GEMM) lines with mutations in protein-encoding genes. These conditional GEMMs are then bred with one or several transgenic mouse lines expressing a site-specific recombinase, most often the Cre recombinase, in a tissue-specific manner. Conditional GEMMs can only be exploited if Cre transgenic mouse lines are available to generate somatic mutations, and thus the number of Cre transgenic lines has significantly increased over the last 15 years. Once produced, these transgenic lines must be validated for reliable, efficient, and specific Cre expression and Cre-mediated recombination. In this overview, the minimum level of information that is ideally required to validate a Cre-driver transgenic line is first discussed. The vagaries associated with validation procedures are considered next, and some solutions are proposed to assess the expression and activity of constitutive or inducible Cre recombinase before undertaking extensive breeding experiments and exhaustive phenotyping. Curr. Protoc. Mouse Biol. 1:1-15. © 2011 by John Wiley & Sons, Inc.