How to choose a line of mice? - briefly
Select a strain whose genetic background aligns with the desired phenotype and obtain it from a reputable supplier with documented health monitoring. Ensure the colony’s age, sex, and breeding conditions match the study’s design requirements.
How to choose a line of mice? - in detail
Selecting an appropriate mouse strain requires a systematic assessment of experimental objectives, genetic attributes, and practical constraints.
First, define the phenotype or biological pathway under investigation. Identify whether the study demands a specific mutation, a reporter construct, or a particular behavioral profile. This step narrows the pool of candidate lines to those that directly exhibit the desired trait.
Second, evaluate the genetic background. Inbred strains such as C57BL/6J, BALB/cJ, or DBA/2J provide uniform allelic composition, reducing variability. Outbred stocks like CD‑1 increase heterogeneity, which may be advantageous for toxicology or pharmacokinetic studies. Consider the influence of background genes on the phenotype of interest; documented strain‑specific differences can confound results if not accounted for.
Third, verify the availability of the line. Commercial vendors (e.g., The Jackson Laboratory, Charles River) and academic repositories maintain detailed catalogs, including breeding status and distribution restrictions. Prioritize strains with robust colony support and clear documentation of genotype verification.
Fourth, assess health status and microbiome considerations. Pathogen‑free colonies, specific‑pathogen‑free (SPF) status, and defined microbiota are essential for immunological or metabolic experiments. Review health certificates and, if necessary, arrange for quarantine and rederivation to meet institutional biosafety requirements.
Fifth, plan breeding logistics. Determine litter size, gestation length, and weaning age to align with project timelines. Examine the reproductive performance of the strain; some lines exhibit low fertility or high neonatal mortality, which can impact cohort size and statistical power.
Sixth, ensure compliance with regulatory and ethical guidelines. Confirm that the chosen line is covered by institutional animal care and use committee (IACUC) protocols, and that any genetic modifications are permissible under local and federal regulations.
A concise checklist for decision‑making:
- Research goal alignment (phenotype, genotype, reporter)
- Genetic background (inbred vs. outbred, known modifiers)
- Source reliability (vendor reputation, colony health)
- Health status (SPF, germ‑free, microbiome profile)
- Breeding characteristics (fecundity, litter size, maturation)
- Regulatory compatibility (IACUC, biosafety, licensing)
Following this structured approach ensures that the selected mouse line optimally supports experimental validity while minimizing unforeseen variables.