Development of Congenic Mouse Strains

Congenic mouse strains play a crucial role in biomedical research by minimizing genetic variability and helping researchers understand how genetic background influences phenotypic traits. These strains are genetically identical except at a single locus—typically the site of a transgene insertion or gene knockout—allowing for precise analysis of specific genetic modifications..

Breaking the Year Barrier Ethically with IVF-assisted Speed Congenics

Producing a congenic mouse strain using traditional, random backcrossing methods takes over 10 generations (upwards of 2.5 years). By selectively breeding individuals containing more of the recipient genome from each generation, speed congenic programs have reduced this time to 65 weeks. 

With its novel speed congenics approach using IVF and single-nucleotide polymorphism (SNP) testing, we can now deliver your congenic colony in 50 weeks, saving time, cost, and the number of animals used in the process.

Creating Congenic Mouse Strains Using IVF

  • Mice are synchronized in age
  • It eliminates the mating potential issues and the isolator fees
  • The number of cages required is drastically reduced
  • One unique health monitoring test is performed
  • One single male is required to produce the next generation
  • The process is fully secured: the selected male sperm is cryopreserved while the other males are maintained alive till the progeny is obtained
  • Only 10 animals per generation are genotyped
  • The SNP analysis is only performed on 5 males from generations 2 to 4
  • The final generation is rederived, and animals are delivered with a SOPF (VAF/Elite®) health status

Marker-Assisted Speed Congenics

Genetic markers mapped to specific locations on each chromosome are employed to evaluate strain-specific genomic polymorphism. The mouse SNP panel we use is composed of 10,000 carefully selected SNP markers and was designed to maximize polymorphism between common inbred strains and provide even coverage of the mouse genome.

IVF-Assisted Speed Congenics Benefits

SpeedTimeline is reduced by 25% compared to traditional speed congenics
Animal ReductionThe number of animals required in the process is reduced by 40%
Reduced CostIVF is a cost-effective approach, providing savings over breeding
Reduced RiskThe process is fully secured with the sperm cryopreservation of the selected male
SOPF (VAF/Elite®) StatusAnimals are rederived and delivered with a SOPF (VAF/Elite®) status

Talk to an Expert

 

Frequently Asked Questions (FAQs) About IVF-assisted Speed Congenics

  • What is a congenic strain?

    A congenic strain is a specialized mouse or rat colony with a defined genetic segment from one inbred strain (the donor) transferred onto the genetic background of another inbred strain (the recipient). Traditionally, his transfer is accomplished through systematic backcrossing and selection. The resulting strain is genetically identical to the recipient strain except for the transferred donor segment and any closely linked genes.

  • What is backcrossing?

    This breeding technique is used in genetics and laboratory animal research. It involves crossing a genetically modified mouse or rat with a wild-type animal of a specific genetic background, selecting offspring that retain the desired genetic modification, and crossing them again with the wild-type strain. This process is repeated for multiple generations.

  • What are the purposes of backcrossing?
    • Transferring a genetic modification from one mouse or rat strain to another with a more desirable genetic background
    • Creating genetically uniform experimental animals by reducing genetic variability
    • Isolating and studying the effects of a specific gene mutation by eliminating other gene differences
  • How pure is the genetic background after speed congenics?

    Speed congenics typically achieve more than 99% of the genetic background, with some remaining regions linked to the selected mutation.