Mike McGrew, University of Edinburgh: Precision breeding and reproductive technologies for bird conservation and tropical poultry adaptation

Studies using the chicken have made very significant contributions to understanding the development of vertebrates owing to the ease in manipulating the chicken embryo. The chick model system has become even more useful with the sequencing of the chicken genome and development of a robust method for transgenesis in the chicken (McGrew et al., 2004). It was also shown that migratory primordial germ cells from the chicken could be cultured in vitro for extended periods and used to generate transgenic chickens (van de Lavoir et al, 2006). My laboratory works on a type of stem cell in birds, the primordial germ cell, which is lineage restricted to producing spermatozoa and eggs of birds. These cells can be used to generate gene edited chickens, chicken which contain precise genetic changes in their genome. We have previously demonstrated that chicken primordial germ cells can be efficiently modified in vitro using transposable elements. I will discuss our use of new CRISPR/Cas9 vector to efficient edit single nucleotides in primordial germ cells and the use of sterile surrogate chicken hosts to increase germline transmission rates and decrease the time needed for production of genome edited chicken. A benefit of this research will be the technology to create bio-banks (frozen aviary) using germ cells. This is needed as the traditional methods used for species cryopreservation using semen and eggs are either inefficient or impossible in birds. Avian bio-banks will aid in the efforts to both manage and conserve both rare and industrial breeds of poultry. The future challenge is to extend biobanking to endangered bird species.