Animal and Avian Sciences, University of Maryland, College Park, Maryland, USA.
RenOVAte Biosciences, Inc., Reisterstown, Maryland, USA.
CRISPR J. 2020 Dec;3(6):523-534. doi: 10.1089/crispr.2020.0047. Epub 2020 Nov 19.
Selective breeding and genetic modification have been the cornerstone of animal agriculture. However, the current strategy of breeding animals over multiple generations to introgress novel alleles is not practical in addressing global challenges such as climate change, pandemics, and the predicted need to feed a population of 9 billion by 2050. Consequently, genome editing in zygotes to allow for seamless introgression of novel alleles is required, especially in cattle with long generation intervals. We report for the first time the use of CRISPR-Cas genome editors to introduce novel allelic variants that have been shown to provide resilience towards human prion pandemics. From one round of embryo injections, we have established six pregnancies and birth of seven edited offspring, with two founders showing >90% targeted homology-directed repair modifications. This study lays out the framework for optimization, unbiased deep-sequencing to identify editing outcomes, and generation of high frequency homology-directed repair-edited calves.
选择性繁殖和基因修饰一直是动物农业的基石。然而，目前通过多代繁殖来引入新等位基因的策略在应对气候变化、大流行病以及到 2050 年预计需要养活 90 亿人口等全球性挑战方面并不实际。因此，需要在受精卵中进行基因组编辑，以实现新等位基因的无缝引入，尤其是在世代间隔较长的牛中。我们首次报道了使用 CRISPR-Cas 基因组编辑工具来引入已被证明对人类朊病毒大流行具有抵抗力的新等位基因变体。通过一轮胚胎注射，我们已经建立了 6 例妊娠和 7 例编辑后代的诞生，其中 2 个供体显示出 >90%的靶向同源定向修复修饰。本研究为优化、无偏深度测序以鉴定编辑结果以及产生高频同源定向修复编辑小牛奠定了框架。
