Biobanking and gene editing of avian germ cells.

The germ cells contain the genetic material that is passed from one generation to the next. We use bird species to understand how germ cells form in the embryo, migrate and interact with their niche in the forming gonad, and finally form sperm and eggs. 

We have developed a serum free culture medium for chicken primordial germ cells which allows these cells to be propagated indefinitely in vitro. This unique culture system has permitted my group to establish germ cell lines from many breeds of chicken. These cells are being used  for the cryopreservation (bio-banking) of commercial and indigenous chicken breeds, and for genome editing to create chicken with precise changes in their genome. We have also developed chicken that are devoid (sterile) of their own sperm or eggs, 'empty nest' chicken, which can be hosts for germ cells from different breeds of chicken. This allows us to restore chicken breeds from frozen material in a manner that supports the 3Rs (Reduction, Refinement, Replacement). In the future, we hope to apply these technologies to all bird species. 

A unique characteristic of germ cells is their ability to turn into pluripotent cells when propagated in culture. We are attempting to understand the mechanisms controlling this process and produce avian cells for the study of gene function, disease resistance and cellular agriculture.

Our research will help scientists identify the genes that are important for heathy birds and to protect and conserve bird species.

Pigeons from Chickens: Mike McGrew at TEDxDeExtinction

On March 15, 2013 at the National Geographic Society, twenty-five thought provoking talks by leading scientists and conservationists were captured on video on the concept of de-extinction of species. What was all the fuss about? What do new genetic technologies offer for bird conservation? Here were my thoughts on the subject.

https://www.youtube.com/watch?v=ByuWS1bBwpc

Mike McGrew is a group leader at The Roslin Institute, UK. He obtained his PhD from Boston University and pursued a research program in embryology at the IBDM in France. There, he was part of a research group that discovered a basic mechanism controlling the timing of the formation of body segments in vertebrates, now known as the ‘segmentation clock’. Afterwards, he joined The Roslin Institute in 2001 to help develop transgenesis in chickens for use in developmental biology and bio-pharming.

His laboratory works on a special stem cell from birds, the primordial germ cell, which makes the sperm and eggs. These cells can be used to produce gene edited chickens, chicken which contain precise genetic changes in their genome.

A benefit of this research will be the technology to create bio-banks (frozen aviaries) 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.