In recent years, as the biomedical industry has flourished, the resources of laboratory rodent strains have expanded, and the demand for quality laboratory rodents has increased. A critical concern for laboratory animal providers is to avoid genetic drifting and genetic contamination in order to deliver high-quality and reliable laboratory animals to researchers.
GemPharmatech has developed a strict breeding management system that ensures the genetic quality of various mouse strains is consistent with international standards and maintains genetic stability in long-term breeding and commercial production. This system was developed based on our many years of experience in breeding laboratory animals.
The central premise of breeding all inbred and pure strains of mice is that the animals' homozygosity and genetic purity must be maintained, and all strains must have detailed records of strain breeding and pedigree charts. Our breeding management system strictly controls and reduces genetic contamination and drift during the breeding process, providing researchers with high-quality animals that have consistent and genetically stable features.
Our mouse population structure is a compact pyramid, with production lines consisting of a foundation group, a pedigree expansion group, and a production group.
Foundation group: sibling pairs, up to three generations are
maintained simultaneously; cryopreservation of genetic material and resuscitation after 10 generations of continuous breeding;
annual SNP monitoring.
Pedigree expansion group: all sibling pairings are within 2
generations, up to 5 generations of common ancestors, annual SNP monitoring with statistical assessment.
Product group: all sibling pairings are within 2 generations, up
to 5-10 generations of common ancestors, annual SNP
monitoring with statistical assessment.
We ensure continuous and uninterrupted breeding of a large number of mouse strains for at least 50 years by employing this system. The population has only passed down two generations, reducing the risk of genetic variation and drift during breeding.
Genetic Monitoring Systems
GemPharmatech uses single nucleotide polymorphisms (SNPs) to track the genetics of live breeding colonies at each of our facilities.
GemPharmatech chose 19 autosomes and 1 X chromosome for various inbred strains, selected monitoring loci on each chromosome at approximately equal distances, and targeted some strain-specific genetic loci by consulting academic papers to construct a library of nearly one thousand specific SNP monitoring loci. On this premise, we have built a panel of 96 SNPs for each inbred or isogenic inbred line, which is adequate to distinguish all the in-house inbred strains and to ensure the genetic stability of each line.
GemPharmatech conducts annual genetic monitoring of the foundation groups of select lines and the production groups of select lines. In addition, we sample inbred background lines each year to ensure the stable genetic background for all newly engineered mouse strains.