Development of an Embryo Cryopreservation Program in Laboratory Animals

NIH动物遗传资源(NIHAGR)保存了几个动物物种，以及一个物种内许多无价的基因类型，这些基因被用作生物医学研究的模型。为了保护这些动物模型，建立了胚胎库，作为一种经济手段来无限期地保存这些啮齿动物和兔子的种群和品系。冷冻保存的胚胎通过保护其免受疾病、生殖失败、自然灾害或遗传污染的损失，确保了基因的可用性。胚胎冷藏库通过提供一个资源来定期重新获得确定的基因类型，以重新标准化或测试基础育种群体，从而将遗传漂移造成的变化降至最低。例如，在过去的一年里，1984年储存的胚胎(B6E(84)/N和C3E(84)/N)被用来生产活体动物，用于通过皮肤移植进行常规遗传监测。这些动物来自更早的育种世代，被用作测试当前NIHAGR C57BL/6N和C3H/HEN基础群体的遗传漂移的对照。作为公认的实验动物物种保存库，NIHAGR经常根据生物医学研究社区的要求提供繁殖配对。与运送活体动物相比，冷冻胚胎代表了一种更简单、更人道、更容易将所需模型运送到世界各地的方法。胚胎处理、冷冻保存和移植程序的另一个重要好处是消除了一些小鼠疾病的垂直传播。基因和物种差异继续影响这一努力的效率。

The NIH Animal Genetic Resource (NIHAGR) maintains several animal species, and many invaluable genotypes within a species, which are used as models in biomedical research. To protect these animal models, an embryo bank was established as an economical means to indefinitely preserve these stocks and strains of rodents and rabbits. Cryopreserving embryos ensures the availability of a genotype by safeguarding it against loss due to disease, reproductive failure, natural catastrophe or genetic contamination. The embryo cryobank minimizes changes due to genetic drift by providing a resource from which to periodically rederive defined genotypes for restandardization or testing of foundation breeding colonies. During the past year, for example, embryos banked in 1984 (B6e(84)/N and C3e(84)/N) were used to produce live animals for use in routine genetic monitoring by skin grafting. These animals, from a much earlier breeding generation, were used as controls for testing genetic drift in current NIHAGR C57BL/6N and C3H/HeN foundation colonies. As a recognized repository for laboratory animal species, the NIHAGR routinely provides breeding pairs upon request throughout the biomedical research community. Rather than shipping live animals, cryopreserved embryos represent a simpler, more humane and easier method to transport requested models worldwide. Another important benefit of embryo handling, cryopreservation, and transfer procedures is to eliminate the vertical transmission of some murine diseases. Genotype and species differences continue to impact on the efficiency of this effort.