Genesis 2016 Mar 25. doi: 10.1002/dvg.22938. [Epub ahead of print]
Koentgen, F; Lin, J; Katidou, M; Chang, I; Khan, M; Watts, J; Mombaerts, P
Ozgene Pty Ltd, Bentley, WA, Australia. Max Planck Research Unit for Neurogenetics, Frankfurt, Germany.
Gene targeting in embryonic stem (ES) cells remains best practice for introducing complex mutations into the mouse germline. One aspect in this multistep process that has not been streamlined with regard to the logistics and ethics of mouse breeding is the efficiency of germline transmission: the transmission of the ES cell-derived genome through the germline of chimeras to their offspring. Here we have developed a method whereby male chimeras transmit exclusively the genome of the injected ES cells to their offspring. The new technology, referred to as goGermline, entails injecting ES cells into blastocysts produced by superovulated homozygous Tsc22d3 floxed females mated with homozygous ROSA26-Cre males. This cross produces males that are sterile due to a complete cell-autonomous defect in spermatogenesis. The resulting male chimeras can be sterile but when fertile, they transmit the ES cell-derived genome to 100% of their offspring. We validated the method extensively and in two laboratories for gene-targeted ES clones that were derived from the commonly used parental ES cell lines Bruce4, E14, and JM8A3. The complete elimination of the collateral birth of undesired, non-ES cell-derived offspring in goGermline technology fulfills the reduction imperative of the 3R principle of humane experimental technique with animals. This article is protected by copyright. All rights reserved.
The team at Ozgene has over two decades of experience creating customised knockout and knock-in mice for pivotal medical research globally. Over 400 scientific publications are based on research using Ozgene mice.